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Circa 1942 - Block A at Bletchley Park in Bletchley, Buckinghamshire on 13 September 2021.
Grade II listed.
The following is from the Historic England website.
Name: Block A at Bletchley Park
Designation Type: Listing
Grade: II
List UID: 1391792
BUILDING: adapted spider block.
DATE: 1942
ARCHITECT: highly-adapted spider block plan purpose-built by Ministry of Works for Government Code and Cipher School
MATERIALS: steel frame with pre-cast concrete floors and roofs. Painted Fletton brick walls, metal windows.
PLAN: E-plan building, comprising an east-west range with three ranges projecting forward from this to the south. On the east side of the western spur a bay window marks the office of Frank Birch, Head of the Naval Section.
EXTERIOR: two storeys with flat roof. Regular runs of mainly four-light steel-framed windows to both storeys (some lengthened at some stage) with tile sills. Doors to south ends of each spur. External steel staircases to first floors of west and east spurs. Projecting open-sided porch on north side of the spine range.
INTERIORS: although the building has undergone considerable alteration to service its post-war uses, until recently most of the corridors and walls were of wartime date. In 2004 the eastern spur and part of the spine range were gutted to create exhibition spaces. Sub-divisions of the building are legible from structural compartments.
HISTORY: in 1939 Bletchley Park became a dispersal home to the Foreign Office's Government Code and Cipher School. It became the focal point of inter-service intelligence activities, the place where German codes (notably those encrypted using the Enigma machine) were deciphered, the significance of decrypts assessed, and intelligence passed to appropriate ministries and commands. Bletchley Park has become celebrated for its contribution to the Allied victory, as well as for its contribution to the development of information technology. As the organisation enlarged new buildings had to be provided, firstly wooden huts and, from 1942, more permanent brick blocks.
Block A, with Block B, was conceived in mid 1941 as an extension to the overcrowded wooden huts and first occupied in August 1942. They formed the first wave of purpose-built structures on the site, responding to the increased volume of decrypts and the desire to create an effective military intelligence centre. Initially it housed the both the Naval and the Air Sections. The former, on the ground floor, took on functions previously carried on in Hut 4. These included intelligence analysis of naval traffic decrypted by Hut 8, non-Enigma cryptography, crib research, and plotting. In addition, Hagelin cipher machines were installed. After analysis material was sent to the Admiralty. The Air Section, on the first floor, included the Meteorological Section (which, for instance, supplied weather forecasts which would help Coastal Command and predict the movements of U-boats and shipping), and SALU (a sub-section mainly concerned with intelligence on German bomber and reconnaissance aircraft). In mid 1943 the Air Section moved to Block F, enabling the Naval Section to take over all of Blocks A and B.
After the war the building - which was considerably adapted for its future uses - accommodated various bodies, notably (early 1950s-late 1970s) a teacher training college and from 1977 the Civil Aviation Authority. The latter left the site in 1993, since when the building has been the responsibility of the Bletchley Park Trust, and stood largely unoccupied for ten years. In 2004 the building was partly stripped out by the Trust to create a new exhibition space.
SUMMARY OF IMPORTANCE: Like Block B, which is already listed, Block A's importance is principally historical, although the physical survival of the building which reflects the scale of the operation at Bletchley is important. The blocks are among the buildings which demonstrate the first instances on the site of the construction of more permanent buildings, ones moreover specifically designed for the personnel and functions which they were to house. They stand markedly in contrast to the small and temporary wooden huts they succeeded. Not only does Block A have a significant relationship to Block B, but also to the lake and landscape and to all the other wartime buildings, several of which it had close operational links with. Bletchley Park is renowned for its part in breaking the German Enigma code, and in contributing to the Allied victory (especially in the Battle of the Atlantic). Block A played an important part in this achievement from 1941 onwards. Architecturally, like Block A, Block B survives externally little altered, and its crisp and functional appearance reflects Bletchley Park's increasing scale and reliance on a large staff and complex electronic machinery. Internally much of the building retains the main components of its wartime layout, although sections of the building have been gutted.
Circa 1942 - Block B at Bletchley Park in Bletchley, Buckinghamshire on 13 September 2021.
Grade II listed.
The following is from the Historic England website.
Name: Block B at Bletchley Park
Designation Type: Listing
Grade: II
List UID: 1391363
Block B. 1942 by HM Office of Works, adapted in consultation with GCCS from a MOW Temporary Office Design.
HISTORY: the headquarters of the Foreign Office's Government Code & Cypher School was established at Bletchley Park in 1939. It has become celebrated for its contribution to Allied victory in the Second World War, and is also renowned for its contribution to the development of information technology.
Block B, was conceived in mid-1941 as an extension to the overcrowded huts, and completed in late summer 1942. They formed the first wave of purpose-built structures on the site, which responded to the increased volume of decrypts and the desire to create an effective military intelligence centre. It originally housed the Naval and Air Sections. The ground floor was used by the Registry for the western European Cryptography Section: other parts were used by the Japanese Cryptography Section. From later in 1943 the Naval Section took over the block. After the war the building was first used as a National Service Hostel: in mid 1950 various alterations took place to convert the block into accommodation for the teacher training college which had been established in 1947. Subsequent modifications took place in the late 1970s when the Civil Aviation Authority took over the block. Empty since 1993, the block has recently (2004) been adapted for use as a museum.
MATERIALS: steel frame with pre-cast concrete floors and roofs. Painted Fletton brick walls, metal windows.
PLAN: attached to Block A to west. Dog-leg plan, with spurs to south, east of the main entrance, and to the north . EXTERIOR: two storeys and basement, with higher entrance block at west end; tall boiler house chimney within east range. Entrance with fluted pilasters and upswept canopy. Plain brick exteriors with regular fenestration, mainly consisting of rectangular twelve-pane metal casement windows; those along the south end of the southern spur have been altered through the later insertion of taller openings. Concrete bands at first floor and roof levels. Later single storey timber-clad extension to north of no interest.
INTERIOR: considerably altered. The entrance lobby has been enlarged, through the demolition of some war time rooms (in the 1950s) and leads to an open staircase with tubular steel railings. Smaller staircase at north end of east range. Each floor formerly consisted of a spine corridor with offices on each side (or WCs along the north side of the main range). The centre and western parts of the ground and first floors have been opened out to create display areas, although the size and location of the wartime offices is still sensed through the exposed steel and concrete beams, under which the original plasterboard partitions were positioned. Some individual rooms remain at the east end of the building, but many of these date from the 1950 conversion to study bedroom use, which used clay brick construction for the walls (some of the clay blocks walls date from the war time construction). The arrangements of war time structures, especially with regard to pantry and store facilities can still be discerned in the areas of the building which have not seen recent change, through changes in fenestration and identification of war time and later materials that still survive.
SUMMARY OF IMPORTANCE: Block B's importance is principally historical, although the physical survival of the building which reflects the scale of the operation at Bletchley is important. Block B demonstrates the first approach of building more permanent buildings on the site using a bespoke design after careful planning. It has a significant relationship to the lake and landscape as well as the other war time buildings that still survive. Bletchley Park is renowned for its part in breaking the German Enigma code, and in contributing to Allied victory (especially in the Battle of the Atlantic). Block B played an important role in this achievement. The building is one of a number of structures at Bletchley Park which clearly reflects the development of the complex. Architecturally the building possesses some outward interest as an increasingly rare example of a rapidly constructed wartime office building, and retains its original crisply functional appearance. The interior has been substantially altered and little of the surviving fabric dates from the crucial period of the block's history.
Apart from the colour scheme Iranian Tomcats were largely the same as jets built for the US Navy around the same time. Some cryptographic equipment wasn't fitted and since the jets didn't operate from aircraft carriers they had a different arresting hook. A change made in service was that the doors that covered the retractable air-to-air refuelling probe were removed, leaving it exposed. The reason was that, in particular when refuelling from a basket mounted to the flying boom of the Iranian Air Forces' Boeing 707 tankers, there was a risk of the doors being damaged and subsequently sucked into the Tomcat's starboard engine. During wartime, for instance during the 1991 Gulf War and the 2003 Invasion of Iraq, the US Navy also often removed these doors, as you can see on my F-14D. they tanked from similar baskets attached to USAF KC-135s.
A US Navy WAVE sets the Bombe rotors prior to a run
The US NAvy cryptanalytic Bombes had only one purpose: Determine the rotor settings used on the German cipher machine ENIGMA. Originally designed by Joseph Desch with the National Cash Register Company in Dayton, Ohio, the Bombes worked primarily against the German Navy's four-rotor ENIGMAs. Without the proper rotor settings, the messages were virtually unbreakable. The Bombes took only twenty minutes to complete a run, testing the 456,976 possible rotor settings with one wheel order. Different Bombes tried different wheel orders, and one of them would have the final correct settings. When the various U-boat settings were found, the Bombe could be switched over to work on German Army and Air Force three-rotor messages.
Source: National Cryptologic Museum
Comment on the above
The four rotor system had 26^4 or 456,976 settings whilst the theree rotor system had 26^3 or 17,756 settings. It looks like the problem scale in a linear way as it took 50 seconds to check 17,756 setting (~350 per second) while the four rotor solution in 20 minutes is ~ 380 settings per second.
I also think the designer Joseph Desch sounds like a remarkable engineer that I never heard of before.
Bombe on Wikipedia
Once the British had given the Americans the details about the bombe and its use, the US had the National Cash Register Company manufacture a great many additional bombes, which the US then used to assist in the code-breaking. These ran much faster than the British version, so fast that unlike the British model, which would freeze immediately (and ring a bell) when a possible solution was detected, the NCR model, upon detecting a possible solution, had to "remember" that setting and then reverse its rotors to back up to it (meanwhile the bell rang).
Source of following material : National Cryptologic Museum
Diagonal Board is the heart of the Bombe unit. Electrically, it has 26 rows and 26 columns of points, each with a diagonal wire connection. These wires connect each letter in a column with the same position in each row. A letter cannot plug into itself; these are known as "self-steckers." The resulting pattern is a series of diagonal lines. The purpose of the diagonal board is to eliminate the complications caused by the Enigma's plugboard. Given specific rotor settings, only certain plugboard settings can result in the proper encrypted letter. The diagonal board disproved hundreds of rotor settings, allowing for only a few possibly correct settings to result in a "strike".
Amplifier Chassis had two purposes, first to detect a hit and second to determine if it was useful. It provided the tie-in from the diagonal board, the locator, and the printer circuits.
Thyratron Chassis was the machine's memory. Since the wheels spun at such a high speed, they could not immediately stop rotating when a correct hit was detected. The Thyratron remembered where the correct hit was located and indicated when the Bombe has rewound to that position. It also told the machine when it had completed a run and gave the final stop signal.
Switch Banks tell the Bombe what plain to cipher letters to search for. Using menus sent to the Bombe deck by cryptanalysts, WAVES set each dial using special wrenches. 00 equates to the letter A and 25 to the letter Z. The dials work together in groups of two. One dial is set to the plain test letter and the other to its corresponding cipher letter as determined by cryptanalysts. There are sixteen sets of switch banks, however, only fourteen were required to complete a run. As the machine worked through the rotor settings, a correct hit was possible if the electrical path in all fourteen switch banks corresponded to each of their assigned plaintext/cipher combinations.
Wheel Banks represent the four rotors used on the German U-boat Enigma. Each column interconnects the four rotors, or commutators, in that column. The top commutator represented the fourth, or slowest, rotor on the Enigma, while the bottom wheel represented the rightmost, or fastest, rotor. The WAVES set the rotors according to the menu developed by the cryptanalysts. The first were set to 00, and each set after that corresponded to the plain/cipher link with the crib (the assumed plain test corresponding to the cipher text.) Usually this meant that each wheel bank stepped up one place from the one on its left. When the machine ran, each bottom rotor stepped forward, and the machine electrically checked to see if the assigned conditions were met. If not, as was usually the case, each bottom wheels moved one more place forward. However, the bottom commutator moved at 850 rpm, so it only took twenty minutes to complete a run of all 456,976 positions.
Printer automatically printed the information of a possible hit. When the Bombe determined that all the possible conditions had been met. it printed wheel order, rotor settings and plugboard connections.
Motor Control Chassis controlled both forward and reverse motors. The Bombe was an electromechanical machine and required a number of gauges for monitoring. It also needed a Braking Assembly to slow the forward motion when a hit was detected and to bring the machine to a full stop when a run was completed.
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A compact experiment aimed at enhancing cybersecurity for future space missions is operational in Europe’s Columbus module of the International Space Station, running in part on a Raspberry Pi Zero computer costing just a few euros.
“Our CryptIC experiment is testing technological solutions to make encryption-based secure communication feasible for even the smallest of space missions,” explains ESA software product assurance engineer Emmanuel Lesser. “This is commonplace on Earth, using for example symmetric encryption where both sides of the communication link share the same encryption key.
“In orbit the problem has been that space radiation effects can compromise the key within computer memory causing ‘bit-flips’. This disrupts the communication, as the key on ground and the one in space no longer match. Up to now this had been a problem that requires dedicated – and expensive – rad-hardened devices to overcome.”
Satellites in Earth orbit might be physically remote, but still potentially vulnerable to hacking. Up until recently most satellite signals went unencrypted, and this remains true for many of the smallest, cheapest mission types, such as miniature CubeSats
But as services delivered by satellites of all sizes form an increasing element of everyday life, interest in assured satellite cybersecurity is growing, and a focus of ESA’s new Technology Strategy for this November’s Space19+ Ministerial Council
.
CryptIC, or Cryptography ICE Cube, - the beige box towards the top of the image, has been a low-cost development, developed in-house by ESA’s Software Product Assurance section and flown on the ISS as part of the International Commercial Experiments service – ICE Cubes for short. ICE Cubes offer fast, simple and affordable access for research and technology experiments in microgravity using compact cubes. CryptIC measures just 10x10x10 cm.
“A major part of the experiment relies on a standard Raspberry Pi Zero computer,” adds Emmanuel. “This cheap hardware is more or less flying exactly as we bought it; the only difference is it has had to be covered with a plastic ‘conformal’ coating, to fulfil standard ISS safety requirements.”
The orbital experiment is operated simply via a laptop at ESA’s ESTEC
technical centre in the Netherlands, routed via the ICE Cubes operator, Space Applications Services in Brussels.
“We’re testing two related approaches to the encryption problem for non rad-hardened systems,” explains ESA Young Graduate Trainee Lukas Armborst. “The first is a method of re-exchanging the encryption key if it gets corrupted. This needs to be done in a secure and reliable way, to restore the secure link very quickly. This relies on a secondary fall-back base key, which is wired into the hardware so it cannot be compromised. However, this hardware solution can only be done for a limited number of keys, reducing flexibility.
“The second is an experimental hardware reconfiguration approach which can recover rapidly if the encryption key is compromised by radiation-triggered memory ‘bit flips’. A number of microprocessor cores are inside CryptIC as customisable, field-programmable gate arrays (FPGAs), rather than fixed computer chips. These cores are redundant copies of the same functionality. Accordingly, if one core fails then another can step in, while the faulty core reloads its configuration, thereby repairing itself.”
In addition the payload carries a compact ‘floating gate’ dosimeter to measure radiation levels co-developed by CERN, the European Organisation for Nuclear Research, as part of a broader cooperation agreement
.
And as a guest payload, a number of computer flash memories are being evaluated for their orbital performance, a follow-on version of ESA’s ‘Chimera’ experiment which flew on last year’s GomX-4B CubeSat
.
The experiment had its ISS-mandated electromagnetic compatibility testing carried out in ESTEC’s EMC Laboratory
.
“CryptIC has now completed commissioning and is already returning radiation data, being shared with our CERN colleagues,” adds Emmanuel. “Our encryption testing is set to begin in a few weeks, once we’ve automated the operating process, and is expected to run continuously for at least a year.”
Credits: ESA; CC BY-SA 3.0 IGO
I went to a Cyber Risk meeting the other day in this glorious building which I think used to be the Patent Office. Anyway, the meeting was in a glass box above which was this marvellous skylight, and since the sun had well and truly set, the blue light was just too much for me to miss. The four photographs are organised vaguely in a Fibonacci pattern, which is relevant to cryptography, as much as it is relevant to photography. The background is the snow storm that hit as we were having the meeting, with a background made up of: (a) my suit trousers material; (b) the back of a book that was in the library that surrounded the glass box; and (c) a page of text from inside the book. Of course, you cannot read the text or make out the background too well - it is all under a veil of cyber protection...
Calcite, Paint
Thebes, Valley of the Kings, Tomb of Tutankhamun (KV 62).
New Kingdom, 18th Dynasty, Reign of Tutankhamun (1355-1346 BCE).
Tutankhamun's tomb held more than eighty vessels of oils and unguents, but thieves stole most of the contents. This container has a central frieze in which the royal throne name appears in a cryptographic writing, ensuring the survival of the king's name.
King Tut exhibit, Seattle Washington, 2012.
German Soldiers of the "Nachrichtentruppe des Heeres" (Intelligence-troops of the Army) taking a break on the roadside. (Sudetenland, late-1938 ?).
The Nachrichtentruppe des Heeres was the Signal Corps of the Wehrmacht. They were responsible for the laying and upkeep of the communications cables and radio networks. Trained at the "Heeresnachrichtenschule" (Army Intelligence School) in Halle-Dölau, the soldiers were taught telegraphy, cryptography, radio/telephone engineering and foreign languages.
The vehicle pictured, a BMW 309, has been modified for military use with the addition of the rear "Gerätekasten" (Equipment box) and "Kabelspulgerät" (Cable winding device) cable reel in place of the standard boot/trunk. The BMW 309 was a straight-six 34Hp car made from 1934 to 1937, these modified vehicles were given the military designation "Kraftfahrzeug 2 Kübelwagen" (Motor-vehicle 2 Bucket-car). Kraftfahrzeug 2 (Kfz.2) was a designation for all "Nachrichtenkraftwagen" or 'Intelligence motor car' small vehicles and Kfz.15 for all medium-sized vehicles. The term 'Kübelwagen', short for 'Kübelsitzwagen' or bucket-seat car, was used to describe vehicles that were fitted with bucket seats and no doors as the doors were usually removed to allow for quicker exit and entry of the vehicle.
Original Image Source: (unknown)
Crop, repair, upscale, colorize: RyanN81
[The World War 2 colorized photos are apolitical, and are simply for historical interest and research purposes only. Any comments relating to politics, racism or other inappropriate/offensive subjects will be removed].
Louis Braille (/breɪl/; French: [lwi bʁaj]; 4 January 1809 – 6 January 1852) was a French educator and inventor of a system of reading and writing for use by the blind or visually impaired. His system remains virtually unchanged to this day, and is known worldwide simply as braille.
Blinded in both eyes as a result of an early childhood accident, Braille mastered his disability while still a boy. He excelled in his education and received scholarship to France's Royal Institute for Blind Youth. While still a student there, he began developing a system of tactile code that could allow blind people to read and write quickly and efficiently. Inspired by the military cryptography of Charles Barbier, Braille constructed a new method built specifically for the needs of the blind. He presented his work to his peers for the first time in 1824.
In adulthood, Braille served as a professor at the Institute and had an avocation as a musician, but he largely spent the remainder of his life refining and extending his system. It went unused by most educators for many years after his death, but posterity has recognized braille as a revolutionary invention, and it has been adapted for use in languages worldwide. (Wikipedia)
Boeing C-135C Stratolifter USAF 61-2669 ``Speckled Trout`` 412th FLTS @ Edwards AFB, CA Note: Speckled Trout was the official nickname given to this modified C-135C, acquired in 1974 and retired on 13 January 2006, that was used by the Secretary and the Chief of Staff of the Air Force for executive transport requirements. Fully equipped with an array of communications equipment, data links and cryptographic sets, the aircraft served a secondary role as a testbed for proposed command and control systems and was also used to evaluate future transport aircraft design.
Bitcoin (₿) is a cryptocurrency invented in 2008 by an unknown person or group of people using the name Satoshi Nakamoto and started in 2009, when its implementation was released as open-source software.
Bletchley Park és un dels llocs més fascinants de la història del segle XX. Aquí, durant la II Guerra Mundial i buscant la manera de desxifrar els codis militars alemanys, en sorgí la informàtica i els ordinadors.
Aquesta de la imatge és una maquina enigma del tipus emprat per la Wehrmacht i la Luftwaffe. Es pot identificar perque els rotors de la part superior porten xifres, i no lletres com al model de la marina. Sense dubte és l'element més famós de la historia del xifratge i la criptologia.
ca.wikipedia.org/wiki/M%c3%a0quina_Enigma
ca.wikipedia.org/wiki/Bletchley_Park
========================================================
Bletchley Park is one of the most amazing historical places related to the XX Century in general and to WWII in particular. Here, during the colossal effort to crack the german military codes, computers and computing science were born (or at least had their main intial development).
This is a Wehrmacht & Luftwaffe model Enigma. You can identify it by the numbers in the rotors. The more famous navy Enigma (M), had letters on them. The Enigma machine is without doubt the most famous icon in the history of cryptology
www.youtube.com/watch?v=JJm4-lqRJDc
en.wikipedia.org/wiki/Enigma_machine
cryptomuseum.com/crypto/enigma/i/index.htm
The emulator (all the site is wonderful):
users.telenet.be/d.rijmenants/en/enigmasim.htm
en.wikipedia.org/wiki/Bletchley_Park
www.bletchleypark.org/content/museum.rhtm
For an impresive virtual visit, take a look to these videos:
The Enigma Machine played a key role in World War II. The German military depended on the Enigma Machine to encrypt communications, but the Allies invested a tremendous amount of effort in decryption and achieved significant success. This provided the Allies a large advantage.
I believe this is a German Wehrmacht (military) Enigma (please let me know if that is not correct). At the upper right are the keys pressed by the operator, entering the characters to be encrypted. At the left, under a cover, are three rotors that turned with each key stroke, changing the encryption code with each letter. Between the two is the lampboard. As the operator pressed a key, the encrypted version of that letter would light on the lampboard.
Seen at the National World War II Museum in New Orleans, Louisiana.
monica trenkler . . . . . . . . . . . . . . . . . . . . . . .
handmade collage on cardboard
45 x 30 cm
Lockheed Martin F-22 "Raptor's" assigned to the 90th Fighter Squadron, Joint Base Elmendorf-Richardson, Alaska, taxi to their parking location at the Royal Australian Air Force Base Amberley flightline for 'Exercise Talisman Sabre 19', July 9. TS19 provides effective and intense training to ensure U.S. Forces are combat ready, capable, interoperable, and deployable on short notice.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22s airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named Senior Sky, this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 Flanker- and MiG-29 Fulcrum-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35s delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35s strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22s price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler. Issues with the F-22s reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35s capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP). A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D. To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35s.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22s thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22s high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22s thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22s aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22s exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22s mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22s stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
Bletchley Park és un dels llocs més fascinants de la història del segle XX. Aquí, durant la II Guerra Mundial i buscant la manera de desxifrar els codis militars alemanys, en sorgí la informàtica i els ordinadors.
La 'Bombe' era una màquina creada per Alan Turing i Gordon Welchman a partir d'un model polonès, que permetia ajudar a desxifrar els codis de la famosa màquina Enigma del III Reich. Tot i que foren destruides totes després de la guerra, amb molt esforç ara han pogut reconstruir-ne una, que funciona com les seves predecesores.
ca.wikipedia.org/wiki/Bletchley_Park
========================================================
Bletchley Park is one of the most amazing historical places related to the XX Century in general and to WWII in particular. Here, during the colossal effort to crack the german military codes, computers and computing science were born (or at least had their main intial development).
The Bombe machine was a device created by Alan Turing and Gordon Welchman to help decyphering the famous german Enigma machine. Although all 'bombes' were destroyed after the war, the team in the museum has rebuilt this full-working bombe. That's why has the name "Phoenix".
www.jharper.demon.co.uk/bombe1.htm
en.wikipedia.org/wiki/Bletchley_Park
www.bletchleypark.org/content/museum.rhtm
For an impresive virtual visit, take a look to these videos:
A U.S. Air Force Lockheed Martin F-22 Raptor flies above Royal Australian Air Force Base Tindal, Australia, March 2, 2017. Twelve Lockheed Martin F-22 Raptors and approximately 200 U.S. Air Force Airmen participated in the first Enhanced Air Cooperation, an initiative under the Force Posture Agreement between the U.S. and Australia.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 Flanker- and MiG-29 Fulcrum-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler. Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP). A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D. To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
Lockheed Martin F-22 "Raptor's" assigned to the 90th Fighter Squadron, Joint Base Elmendorf-Richardson, Alaska, taxi to their parking location at the Royal Australian Air Force Base Amberley flightline for 'Exercise Talisman Sabre 19', July 9. TS19 provides effective and intense training to ensure U.S. Forces are combat ready, capable, interoperable, and deployable on short notice.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22s airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named Senior Sky, this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 Flanker- and MiG-29 Fulcrum-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35s delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35s strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22s price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler. Issues with the F-22s reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35s capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP). A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D. To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35s.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22s thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22s high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22s thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22s aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22s exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22s mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22s stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
A U.S. Air Force Lockheed Martin F-22 "Raptor" flies above Royal Australian Air Force Base Tindal, Australia, March 2, 2017. Twelve Lockheed Martin F-22 "Raptors" and approximately 200 U.S. Air Force Airmen participated in the first Enhanced Air Cooperation, an initiative under the Force Posture Agreement between the U.S. and Australia.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 Flanker- and MiG-29 Fulcrum-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler. Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP). A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D. To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
A Lockheed Martin F-22 Raptor assigned to the 525th Fighter Squadron from Joint Base Elmendorf-Richardson, Alaska, flies away after refueling from a Boeing KC-135 Stratotanker assigned to the 909th Air Refueling Squadron from Kadena Air Base, Japan, during exercise Northern Edge, May 16, 2019, over Alaska. Northern Edge is designed to sharpen participants’ tactical combat skills, to improve command, control and communication relationships and to develop plans and programs across the Joint Force.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 "Flanker"- and MiG-29 "Fulcrum"-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler.[60] Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP).[66] A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D.[83][84] To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
Aquesta maquina xifradora alemana, la Lorenz SZ-42, molt més complicada però amb menys fama que la Enigma, era emprada per les comunicacions més importants, entre Hitler i els seus comandaments d'exèrcits. En teoria, era quasi imposible de 'petar', però els anglesos ho feren possible, i de pasada inventaren els ordinadors! Aquests rotors que es veuen, dotze en total, produien lletres semi-aleatories que “ocultaven” les lletres del text original. Mireu els enllaços que us passo per compendre el funcionament d’aquesta complexa peça d’enginyeria.
Bletchley Park és un dels llocs més fascinants de la historia del segle XX. Aquí, durant la II Guerra Mundial i buscant la manera de desxifrar els codis militars alemanys, en sorgí la informatica i els ordinadors.
es.wikipedia.org/wiki/C%c3%b3digo_Lorenz
ca.wikipedia.org/wiki/Bletchley_Park
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This electromechanical cypher machine, the Lorenz SZ-42, was used by Hitler and his generals for the most important messages. It is much more complex and difficult to crack than the much more famous Enigma machine, but even this one was in the end broken by the people in Bletchley Park. And as a side-product, they invented the computers! Look at my picture of the Colossus for more info. Lorenz twelve rotors produced a pair of pseudo-random characters that masked the plain text character introduced into the machine.
Bletchley Park is one of the most amazing historical places related to the XX Century in general and to WWII in particular. Here, during the colossal effort to crack the german military codes, computers and computing science were born (or at least had their main intial development).
www.youtube.com/watch?v=69uSSXzlmMY&feature=related
en.wikipedia.org/wiki/Lorenz_cipher
www.jproc.ca/crypto/tunny.html
en.wikipedia.org/wiki/Bletchley_Park
www.bletchleypark.org/content/museum.rhtm
For an impresive virtual visit, take a look to these videos:
Somewhat overllooked compared to Alan Turing et al. Tommy flowers, who was an engineer with the General Post Office, created what was arguably the first programmable computer which was used to decrypt the wartime German Lorentz cipher. He grew up in this neighbourhood. The mural is on the pub named after him.
Bitcoin (₿) is a cryptocurrency invented in 2008 by an unknown person or group of people using the name Satoshi Nakamoto and started in 2009, when its implementation was released as open-source software.
Salon-la-Tour is a commune in the Corrèze department in central France.
Violette Szabo, a 22-year-old British agent who was parachuted a second time into France, on 7 June 1944 (where she was to try to help obstructing the movement of German SS units from the south of France to Normandy), was captured near Salon-la-Tour.
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Violette Reine Elizabeth Szabo GC (née Bushell; 26 June 1921 – c. 5 February 1945) was a British-French Special Operations Executive (SOE) agent during the Second World War and a posthumous recipient of the George Cross. On her second mission into occupied France, Szabo was captured by the German army, interrogated, tortured and deported to Ravensbrück concentration camp in Germany, where she was executed.
Violette Szabo was born on 26 June 1921 in Paris, France, of parents Charles George Bushell and Reine Blanche Leroy, as the second child of five and the only daughter.
Szabo's father, son of a publican from Hampstead Norreys, was serving as a British Army driver in France during the First World War when he met her mother, a dressmaker originally from Pont-Remy, Somme. After the war the couple lived in London, where Charles worked as a taxi-driver, car salesman and shopkeeper.
During the early 1930s, as a result of the Great Depression, Violette and her youngest brother, Dickie, lived with their maternal aunt in Picardy, northern France. The family was reunited in South London when Violette was 11 years old. She was an active and lively girl, enjoying gymnastics, long-distance bicycling and ice-skating with four brothers and several male cousins. Violette was regarded as a tomboy, especially after being taught to shoot by her father; her shooting was reputedly very accurate.
While she had temporarily lost the ability to speak English in Picardy, Violette quickly relearned the language while attending school in Brixton. There she was reportedly popular and regarded as exotic owing to her ability to speak another language. Her home life was loving, though she often clashed with her strict father and once ran away to France after an argument. The family, except her monolingual father, would often converse in French.
At the age of 14, Violette went to work for a French corsetière in South Kensington and later worked at retailer Woolworths in Oxford Street. At the outbreak of World War II she was working at Le Bon Marché, a Brixton department store.
In early 1940 Violette joined the Women's Land Army and was sent to carry out strawberry picking in Fareham, Hampshire, but she soon returned to London to work in an armaments factory in Acton. She met Étienne Szabo, a decorated non-commissioned officer in the French Foreign Legion of Hungarian descent, at the Bastille Day parade in London in 1940, where Violette had been sent by her mother, accompanied by her friend Winnie Wilson, to bring home a homesick French soldier for dinner. They married at Aldershot Register Office in Manor Park on 21 August 1940 after a 42-day romance; Violette was 19, Étienne was 31. They enjoyed a week's honeymoon before Étienne set off from Liverpool to fight in the abortive Free French attack on Dakar, Senegal. From there, he went to South Africa before seeing action, again against the Vichy French, in the successful Anglo-Free French campaigns in Eritrea and Syria in 1941. He returned to the UK for a brief leave later in the year.
After her marriage, Violette became a switchboard operator for the General Post Office in central London, working throughout the Blitz. Bored by the job, she enlisted in the Auxiliary Territorial Service (ATS) on 11 September 1941. She was posted to Leicester for initial training before being sent to one of the first mixed anti-aircraft batteries of the 7th Heavy Anti-Aircraft Training Regiment, Royal Artillery in Oswestry, Shropshire for specialised instruction as a predictor and then to the 481st Heavy (Mixed) Anti-Aircraft Battery. After further training in Anglesey, Gunner Szabo and her unit were posted to Frodsham, Cheshire, near Warrington, from December 1941 to February 1942. Szabo found within weeks that she was pregnant, so she left the ATS to return to London for the birth.
Szabo took a flat in Notting Hill, which was to be her home until she left for her second mission to France in June 1944. On 8 June 1942, she gave birth to Tania Damaris Desiree Szabo at St Mary's Hospital while Étienne was stationed at Bir Hakeim in North Africa. The following day, he took part in a valiant defence against the Afrika Korps, escaping with his battalion from the assault of the 15th Panzer Division on 10 June.
Violette sent her baby to childminders while she worked at the South Morden aircraft factory where her father was stationed. During this period, she was informed of her husband's death in action. Étienne had died on 24 October 1942 from chest wounds received while leading his men in a diversionary attack on Qaret el Himeimat, at the beginning of the Second Battle of El Alamein; he had never seen his daughter. It was Étienne's death that made Violette accept an offer to train as a field agent in the British Special Operations Executive (SOE) as her best way of fighting the enemy that killed her husband.
Special Operations Executive
It is unclear how or why Szabo was recruited by F-Section, as her surviving official file is thin, but her fluency in French and her previous service in the ATS probably brought her to the attention of SOE. She would have been invited to an interview regarding war work with E. Potter, the alias of Selwyn Jepson, a detective novelist and the F-Section recruiter. Szabo was given security clearance on 1 July 1943 and selected for training as a field agent on 10 July. She was commissioned as a section leader in the First Aid Nursing Yeomanry, a civilian service often used by SOE as a cover for female agents.
After an assessment for fluency in French and a series of interviews, Szabo was sent from 7–27 August to STS 4, a training school at Winterfold House, and after a moderately favourable report, to Special Training School 24 of Group A at Arisaig in the Scottish Highlands in September and October. Szabo received intensive instruction in fieldcraft, night and daylight navigation, weapons and demolition. Again her reports were mixed, but she passed the course and moved on to Group B.
Szabo was sent to the SOE "finishing school" at Beaulieu, Hampshire, where she learnt escape and evasion, uniform recognition, communications and cryptography, and had further training in weaponry. The final stage in training was parachute jumping, which was taught at Ringway Airport near Manchester. On her first attempt, Szabo badly sprained her ankle and was sent home for recuperation, spending some time in Bournemouth (it was this ankle that was to fail her later in France). She was able to take the parachuting course again and passed with a second class in February 1944. On 24 January 1944, Szabo made her will, witnessed by Vera Atkins and Major R. A. Bourne Paterson of SOE, naming her mother, Reine, as executrix and her daughter Tania as sole beneficiary.
In 2012 Max Hastings wrote that Szabo was "adored by the men and women of SOE both for her courage and endless infectious Cockney laughter", while Leo Marks remembered her as "A dark-haired slip of mischief....She had a Cockney accent which added to her impishness".
First mission
Due to the ankle injury, Szabo's first deployment was delayed, but it was during her second course at Ringway that she first met Philippe Liewer (d. c. 1948). While in London she also socialised with Bob Maloubier, so SOE decided she would work as a courier for Liewer's Salesman circuit. However, the mission was postponed when F Section received a signal from Harry Peulevé's (codename Jean) Author circuit warning that several members of the Rouen-Dieppe group had been arrested, including Claude Malraux (codename Cicero; brother of novelist Andre Malraux) and radio operator Isidore Newman. This extra time meant Szabo could be sent for a refresher course in wireless operation in London, and it was then that Leo Marks, SOE's cryptographer, seeing her struggle with her original French nursery rhyme, gave Szabo his own composition, The Life That I Have as her code poem.
On 5 April 1944, Szabo and Liewer were flown from RAF Tempsford in Bedfordshire in a US B-24 Liberator bomber and parachuted into German-occupied France, near Cherbourg. Her cover was that she was a commercial secretary named Corinne Reine Leroy (the latter two names being her mother's first and maiden names), who was born on 26 June 1921 (her real birthdate) in Bailleul, and who was a resident of Le Havre, which gave her reason to travel to the Restricted Zone of German occupation on the coast.
Under the code name "Louise", which happened to be her nickname (she was also nicknamed "La P'tite Anglaise", as she stood only 5'3" tall), she and SOE colleague Philippe Liewer (under the name "Major Charles Staunton"), organiser of the Salesman circuit, tried to assess the damage made by the German arrests, with Szabo travelling to Rouen, where Liewer could not go as a wanted man (both he and Maloubier were on wanted posters with their codenames), and to Dieppe to gather intelligence and carry out reconnaissance. It soon became clear that the circuit, which originally involved over 120 members (80 in Rouen and 40 on the coast) had been exposed beyond repair. Szabo returned to Paris to brief Liewer, and in the two days, before they were due to depart, she bought a dress for Tania, three frocks and a yellow sweater for herself, and perfume for her mother and herself. While the destruction of Salesman was a heavy blow to SOE, her reports on the local factories producing war materials for the Germans were important in establishing Allied bombing targets.
She returned to England by Lysander, piloted by Bob Large, DFC, of the RAF, on 30 April 1944, landing after a stressful flight in which the plane was hit by anti-aircraft fire over Chateaudun, and Szabo was thrown about the body of the plane. Large had turned off the intercom when attacked and did not turn it back on for the rest of the flight, so when the plane landed heavily due to a burst tyre, and he went to get Szabo out, she (thinking they had been shot down and not having seen her blond pilot) let Large have a volley of abuse in French, mistaking him for a German. When she realised what had really happened, he was rewarded with a kiss. Philippe Liewer returned at the same time in another Lysander. On 24 May 1944 Szabo was promoted to Ensign in the FANY.
After two aborted attempts, due to stormy weather on the night of 4/5 June and the abandonment of the intended landing ground on 5/6 June by the Resistance reception committee because of German patrols, Szabo and three colleagues were dropped by parachute from a USAAF Liberator flown from RAF Harrington in Northamptonshire onto a landing field near Sussac on the outskirts of Limoges early on 8 June 1944 (immediately following D-Day, and Tania Szabo's second birthday).
Szabo was part of a four-person team sent to operate in the department of Haute Vienne with the circuit codename 'Salesman II', led by her SOE commander Philippe Liewer (now codenamed Hamlet), whose rolled-up Rouen circuit had been 'Salesman', and including Second Lieutenant Jean-Claude Guiet (codenames Claude and Virgile) of the US Army as wireless operator (W/O), and Bob Maloubier (alias Robert 'Bob' Mortier; codenames Clothaire and Paco), Violette and Liewer's friend and comrade of SOE who was to act as military instructor to the local Maquis, and who had worked as weapons instructor and explosives officer for Liewer on the original Salesman I circuit. For this mission, Szabo's cover was that she was a Mme Villeret, the young widow of an antiques dealer from Nantes. It is possible Szabo had twisted an ankle on landing.
Upon arrival, she was sent to co-ordinate the activities of the local maquis in sabotaging communication lines during German attempts to stem the Normandy landings. When he arrived in the Limousin, Philippe Liewer found the local maquis to be poorly led and less prepared for action than he expected. To better co-ordinate Resistance activity against the Germans, he decided to send his courier, Szabo, as his liaison officer to the more active Maquis of Correze and the Dordogne, led by Jacques Poirier (SOE), head of the renamed Digger circuit, who had taken over from Harry Peulevé of the Author circuit, upon the latter's arrest. However, due to poor intelligence gathering by the local Resistance, Liewer was unaware that the 2nd SS Panzer Division was making its slow journey north to the Normandy battlefields through his area.
At 9.30 am on 10 June Szabo set off on her mission, not inconspicuously by bicycle as Liewer would have preferred, but in a Citroen driven by a young maquis section leader, Jacques Dufour ('Anastasie'). He had insisted upon using the car, even though the Germans had forbidden the use of cars by the French after D-Day, to drive her half of the 100 kilometres (62 mi) of her journey. At her request to Liewer, Szabo was armed with a Sten gun and eight magazines of ammunition. She was dressed in a light suit, flat-heeled shoes and no stockings. On their way across the sunlit fields of south-central France they picked up Jean Bariaud, a 26-year-old Resistance friend of Dufour, who was meant to accompany them on the return journey.
Their car raised the suspicions of German troops at an unexpected roadblock outside of Salon-la-Tour that had been set up to find Sturmbannführer Helmut Kämpfe, a battalion commander of the 2nd SS Panzer Division, who had been captured by the local resistance. When Dufour slowed the car, the unarmed Bariaud was able to escape and later warn the Salesman team of the arrest of his two companions.
According to Minney and Vickers, when they had stopped, Szabo and Dufour leapt from the car, he to the left and she to the right and the cover of a tree, as Dufour opened fire. A gun battle ensued during which a woman emerging from a barn was killed by the Germans. As armoured cars arrived at the scene, Szabo crossed the road to join Dufour, and they leapt a gate, before running across a field towards a small stream. They then ran up a hill towards some trees, when Szabo fell and severely twisted an ankle. She refused Dufour's offer of help, urging him to flee, and, dragging herself to the edge of the cornfield, she struggled to an apple tree. Standing behind the tree, she then provided Dufour with covering fire, allowing him to make his escape to hide in a friend's barn. Szabo fought the Germans for thirty minutes, killing a corporal, possibly more, and wounding some others. Eventually, she ran out of ammunition and was captured by two men who dragged her up the hill to a bridge over a railway. She was hot, dishevelled, and in pain. Szabo was questioned by a young officer whose armoured car had drawn up nearby. She was then taken away. Szabo's captors were most likely from the 1st Battalion of 3rd SS Panzer Grenadier Regiment Deutschland (Das Reich Division) whose commanding officer was the missing Sturmbannführer Kämpfe.
In R.J. Minney's biography, as above, she is described as putting up fierce resistance with her Sten gun, although German documents of the incident record no German injuries or casualties. A recent biography of Vera Atkins, the intelligence officer for the French section of SOE, notes that there was a great deal of confusion about what happened to Szabo—the story was revised four times—and states that the Sten gun incident "was probably a fabrication". Szabo's most recent biographer, Susan Ottaway, includes the battle in her book, as does Tania Szabo in hers, and Philip Vickers in his book on Das Reich. Authors Sarah Helm and Max Hastings express doubt about the story of the battle.
Violette Szabo was transferred to the custody of the Sicherheitsdienst (SD, the SS Security Service) in Limoges, where she was interrogated for four days by SS-Sturmbannführer Kowatch. She gave her name as "Vicky Taylor", the name she had intended to use if she needed to return to England via Spain. (Her reason for choosing this name is unknown, but it may have been a play on szabo being the Hungarian word for "tailor".) From there, she was moved to Fresnes Prison in Paris and brought to Gestapo headquarters at 84 Avenue Foch for interrogation and torture by the Sicherheitsdienst, who by now knew of her true identity and activities as an SOE agent.
With the Allies driving deep into France and George Patton's Third US Army heading towards Paris, the decision was taken by the Germans to send their most valuable French prisoners to Germany. On 8 August 1944, Szabo, shackled to SOE wireless operator Denise Bloch, was entrained with other male and female prisoners, including several SOE agents she knew, for transfer. At some point in the journey, probably outside Chalons-sur-Marne, an Allied air raid caused the guards to temporarily abandon the train, allowing Szabo and Bloch to get water from a lavatory to the caged male prisoners in the next carriage, the two women both providing inspiration and a morale boost to the suffering men. When the train reached Reims, the prisoners were taken by lorries to a large barn for two nights, where Szabo, still tied at the ankle to Bloch, who was in good spirits, was able to wash some of her clothes in a rudimentary fashion and to speak about her experiences to her SOE colleague Harry Peulevé.
From Reims, via Strasbourg, the prisoners went by train to Saarbrücken and a transit camp in the suburb of Neue Bremm, where hygiene facilities were nonexistent, and food was only indigestible bread crusts. After about ten days, Szabo and most of the other women were sent on to Ravensbrück concentration camp, where over 92,000 women were to die during the war. The exhausted women arrived at this notorious place of disease, starvation, and violence on 25 August 1944 after a terrible eighteen-day journey.
Although she endured hard labour and malnutrition, she helped save the life of Belgian resistance courier Hortense Daman, kept up the spirits of her fellow detainees, and, according to fellow inmate American Virginia d'Albert-Lake, constantly planned to escape. While at Ravensbrück, Szabo, Denise Bloch, Lilian Rolfe and Lake were among 1,000 French women sent to the Heinkel factory at the sub-camp of Torgau. Here they protested and refused to make munitions, and were forced to work in the vegetable cellar outside the camp walls and then to dig potatoes. The British women also made contact with French prisoners at a nearby POW camp who, being better fed, provided them with extra rations and offered to send messages to London with a transmitter they had built (there is no evidence they were successful).
After the Torgau incident, Szabo, Bloch, Rolfe and Lake were part of a group of around 250 prisoners sent back to Ravensbrück on 6 October, where Violette was put to work in the fabric store. In late October 1944, the protest women were transferred to a punishment camp at Königsberg, where they were forced into harsh physical labour felling trees, clearing rock-hard icy ground for the construction of an airfield and digging a trench for a narrow-gauge railway. Violette volunteered for tree-felling in the forest, where the trees gave some shelter from the bitter winds (Lilian and Denise were too ill to join her). In the bitter East Prussian winter of 1944, each day the women were forced to stand for Appell (roll-call) in the early morning for up to five hours before being sent to work, many of them freezing to death. Szabo was dressed only in the summer clothes she had been wearing when sent to Germany and the women received barely any food and slept in frozen barracks without blankets. According to Christine Le Scornet, a seventeen-year-old French girl whom Violette befriended, and Jeannie Rousseau, the co-leader of the Torgau revolt, she maintained her morale, was optimistic about liberation and continued to plan to escape. On 19 or 20 January 1945, the three British agents were recalled to Ravensbrück and sent first to the Strafblock, where they were possibly brutally assaulted and then to the punishment bunker, where they were kept in solitary confinement. The women were already in poor physical condition—Rolfe could barely walk—and the abuse finally weakened Szabo's morale.
Szabo was killed in the execution alley at Ravensbrück, aged 23, on or before 5 February 1945. She was shot in the back of the head while kneeling down, by SS-Rottenführer Schult in the presence of camp commandant Fritz Suhren (who pronounced the death penalty), camp overseer and deputy commandant Johann Schwarzhuber, SS-Scharführer Zappe, SS-Rottenführer Schenk (responsible for the crematorium), chief camp doctor Dr Trommer and dentist Dr Martin Hellinger, from the deposition of Schwarzhuber recorded by Vera Atkins 13 March 1946. Denise Bloch and Lilian Rolfe – neither of whom could walk and were carried on stretchers – were shot at the same time, by order of the highest Nazi authorities; the bodies were disposed of in the camp crematorium. Their clothes were not returned to the camp Effektenkammer (property store) as usually happened after executions.
Along with Szabo, Bloch, and Rolfe, one other member of the SOE was also executed at Ravensbrück: Cecily Lefort. She was killed in the gas chamber sometime in February 1945. Forty-one female Section F SOE agents served in France, some for more than two years, most for only a few months. Twenty-six of them survived World War II. Twelve were executed including Szabo, one was killed when her ship was sunk, two died of disease while imprisoned, and one died of natural causes. Female agents ranged in age from 20 to 53 years.
While there is some confusion about the precise circumstances of her execution, Szabo, along with her male and female colleagues who died in the concentration camps, is recorded by the War Office as having been killed in action. As an agent dressed in civilian clothes operating behind enemy lines, Szabo was regarded by the Germans as a franc-tireur not protected by the Geneva Convention and liable to summary execution. Though she was treated harshly at Ravensbrück, there is no conclusive proof that she was tortured or sexually assaulted by the Germans; her biographer, Susan Ottaway, thinks it unlikely.
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Lockheed Martin F-22 Raptor's assigned to the 90th Fighter Squadron, Joint Base Elmendorf-Richardson, Alaska, taxi to their parking location at the Royal Australian Air Force Base Amberley flightline for 'Exercise Talisman Sabre 19', July 9. TS19 provides effective and intense training to ensure U.S. Forces are combat ready, capable, interoperable, and deployable on short notice.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22s airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named Senior Sky, this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 Flanker- and MiG-29 Fulcrum-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35s delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35s strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22s price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler. Issues with the F-22s reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35s capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP). A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D. To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35s.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22s thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22s high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22s thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22s aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22s exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22s mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22s stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
A formation of Lockheed Martin F-35A "Lightning IIs", from the 388th Fighter Wing and 419th FW, refuel over the Utah Test and Training Range, Utah, as part of a combat power exercise Nov. 19, 2018. The exercise aims to confirm their ability to quickly employ a large force of jets against air and ground targets, and demonstrate the readiness and lethality of the F-35. As the first combat-ready F-35 units in the Air Force, the 388th and 419th FWs at Hill Air Force Base, Utah, are ready to deploy anywhere in the world at a moment's notice.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 "Flanker"- and MiG-29 "Fulcrum"-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler.[60] Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP).[66] A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D.[83][84] To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
Bletchley Park és un dels llocs més fascinants de la historia del segle XX. Aquí, durant la II Guerra Mundial i buscant la manera de desxifrar els codis militars alemanys, en sorgí la informatica i els ordinadors.
Vista interna d'una maquina 'Bombe'. La 'Bombe' fou creada per Alan Turing i Gordon Welchman a partir d'un model polonès, que permetia ajudar a desxifrar els codis de la famosa maquina Enigma del III Reich. Tot i que foren destruides totes despres de la guerra, amb molt esforç ara han pogut reconstruir-ne una, que funciona com les seves predecesores.
ca.wikipedia.org/wiki/Bletchley_Park
========================================================
Bletchley Park is one of the most amazing historical places related to the XX Century in general and to WWII in particular. Here, during the colossal effort to crack the german military codes, computers and computing science were born (or at least had their main intial development).
This is the back side of a Bombe machine, in Bletchley Park. The Bombe machine was a device created by Alan Turing and Gordon Welchman to help decyphering the famous german Enigma machine. Although all 'bombes' were destroyed after the war, the team in the museum has rebuilt this full-working bombe. That's why has the name "Phoenix".
www.jharper.demon.co.uk/bombe1.htm
en.wikipedia.org/wiki/Bletchley_Park
www.bletchleypark.org/content/museum.rhtm
For an impresive virtual visit, take a look to these videos:
Haarajärvi on August 1, 1941 at 10.30. This is how accurately the moment of shooting is recorded in the SA image.
The picture shows Lotta operating a telephone switchboard
Tasks in this section included call broker, radio assignments, telegram, and cryptography. Those working in the war zone were usually stationed in the message battalions of the actual message forces.
SA image # 31284
Photo: Lieutenant L. H. von Willebrand
My son has become fascinated with bitcoins, and so I had to get him a tangible one for Xmas. The public key is imprinted visibly on the tamper-evident holographic film, and the private key lies underneath. (Casascius)
I too was fascinated by digital cash back in college, and more specifically by the asymmetric mathematical transforms underlying public-key crypto and digital blind signatures.
I remembered a technical paper I wrote, but could not find it. A desktop search revealed an essay that I completely forgot, something that I had recovered from my archives of floppy discs (while I still could).
It is an article I wrote for the school newspaper in 1994. Ironically, Microsoft Word could not open this ancient Microsoft Word file format, but the free text editors could.
What a fun time capsule, below, with some choice naivetés…
I am trying to reconstruct what I was thinking. I was arguing that a bulletproof framework for digital cash (and what better testing ground) could be used to secure a digital container for executable code on a rental basis. So the expression of an idea — the specific code, or runtime service — is locked in a secure container. The idea would be to prevent copying instead of punishing after the fact.
Micro-currency and micro-code seem like similar exercises in regulating the single use of an issued number.
Now that the Bitcoin experiment is underway, do you know of anyone writing about it as an alternative framework for intellectual property (from digital art to code to governance tokens)?
IP and Digital Cash
@NORMAL:
Digital Cash and the “Intellectual Property” Oxymoron
By Steve Jurvetson
Many of us will soon be working in the information services or technology industries which are currently tangled in a bramble patch of intellectual property law. As the law struggles to find coherency and an internally-consistent logic for intellectual property (IP) protection, digital encryption technologies may provide a better solution — from the perspective of reducing litigation, exploiting the inherent benefits of an information-based business model, and preserving a free economy of ideas.
Bullet-proof digital cash technology, which is now emerging, can provide a protected “cryptographic container” for intellectual expressions, thereby preserving traditional notions of intellectual property that protect specific instantiations of an idea rather than the idea itself. For example, it seems reasonable that Intuit should be able to protect against the widespread duplication of their Quicken software (the expression of an idea), but they should not be able to patent the underlying idea of single-entry bookkeeping. There are strong economic incentives for digital cash to develop and for those techniques to be adapted for IP protection — to create a protected container or expression of an idea. The rapid march of information technology has strained the evolution of IP law, but rather than patching the law, information technology itself may provide a more coherent solution.
Information Wants To Be Free
Currently, IP law is enigmatic because it is expanding to a domain for which it was not initially intended. In developing the U.S. Constitution, Thomas Jefferson argued that ideas should freely transverse the globe, and that ideas were fundamentally different from material goods. He concluded that “Inventions then cannot, in nature, be a subject of property.” The issues surrounding IP come into sharp focus as we shift to being more of an information-based economy.
The use of e-mail and local TV footage helps disseminate information around the globe and can be a force for democracy — as seen in the TV footage from Chechen, the use of modems in Prague during the Velvet Revolution, and the e-mail and TV from Tianammen Square. Even Gorbachev used a video camera to show what was happening after he was kidnapped. What appears to be an inherent force for democracy runs into problems when it becomes the subject of property.
As higher-level programming languages become more like natural languages, it will become increasingly difficult to distinguish the idea from the code. Language precedes thought, as Jean-Louis Gassée is fond of saying, and our language is the framework for the formulation and expression of our ideas. Restricting software will increasingly be indistinguishable from restricting freedom of speech.
An economy of ideas and human attention depends on the continuous and free exchange of ideas. Because of the associative nature of memory processes, no idea is detached from others. This begs the question, is intellectual property an oxymoron?
Intellectual Property Law is a Patch
John Perry Barlow, former Grateful Dead lyricist and co-founder (with Mitch Kapor) of the Electronic Frontier Foundation, argues that “Intellectual property law cannot be patched, retrofitted or expanded to contain digitized expression... Faith in law will not be an effective strategy for high-tech companies. Law adapts by continuous increments and at a pace second only to geology. Technology advances in lunging jerks. Real-world conditions will continue to change at a blinding pace, and the law will lag further behind, more profoundly confused. This mismatch may prove impossible to overcome.”
From its origins in the Industrial Revolution where the invention of tools took on a new importance, patent and copyright law has protected the physical conveyance of an idea, and not the idea itself. The physical expression is like a container for an idea. But with the emerging information superhighway, the “container” is becoming more ethereal, and it is disappearing altogether. Whether it’s e-mail today, or the future goods of the Information Age, the “expressions” of ideas will be voltage conditions darting around the net, very much like thoughts. The fleeting copy of an image in RAM is not very different that the fleeting image on the retina.
The digitization of all forms of information — from books to songs to images to multimedia — detaches information from the physical plane where IP law has always found definition and precedent. Patents cannot be granted for abstract ideas or algorithms, yet courts have recently upheld the patentability of software as long as it is operating a physical machine or causing a physical result. Copyright law is even more of a patch. The U.S. Copyright Act of 1976 requires that works be fixed in a durable medium, and where an idea and its expression are inseparable, the merger doctrine dictates that the expression cannot be copyrighted. E-mail is not currently copyrightable because it is not a reduction to tangible form. So of course, there is a proposal to amend these copyright provisions. In recent rulings, Lotus won its case that Borland’s Quattro Pro spreadsheet copied elements of Lotus 123’s look and feel, yet Apple lost a similar case versus Microsoft and HP. As Professor Bagley points out in her new text, “It is difficult to reconcile under the total concept and feel test the results in the Apple and Lotus cases.” Given the inconsistencies and economic significance of these issues, it is no surprise that swarms of lawyers are studying to practice in the IP arena.
Back in the early days of Microsoft, Bill Gates wrote an inflammatory “Open Letter to Hobbyists” in which he alleged that “most of you steal your software ... and should be kicked out of any club meeting you show up at.” He presented the economic argument that piracy prevents proper profit streams and “prevents good software from being written.” Now we have Windows.
But seriously, if we continue to believe that the value of information is based on scarcity, as it is with physical objects, we will continue to patch laws that are contrary to the nature of information, which in many cases increases in value with distribution. Small, fast moving companies (like Netscape and Id) protect their ideas by getting to the marketplace quicker than their larger competitors who base their protection on fear and litigation.
The patent office is woefully understaffed and unable to judge the nuances of software. Comptons was initially granted a patent that covered virtually all multimedia technology. When they tried to collect royalties, Microsoft pushed the Patent Office to overturn the patent. In 1992, Software Advertising Corp received a patent for “displaying and integrating commercial advertisements with computer software.” That’s like patenting the concept of a radio commercial. In 1993, a DEC engineer received a patent on just two lines of machine code commonly used in object-oriented programming. CompuServe announced this month that they plan to collect royalties on the widely used GIF file format for images.
The Patent Office has issued well over 12,000 software patents, and a programmer can unknowingly be in violation of any them. Microsoft had to pay $120MM to STAC in February 1994 for violating their patent on data compression. The penalties can be costly, but so can a patent search. Many of the software patents don’t have the words “computer,” “software,” “program,” or “algorithm” in their abstracts. “Software patents turn every decision you make while writing a program into a legal risk,” says Richard Stallman, founder of the League for Programming Freedom. “They make writing a large program like crossing a minefield. Each step has a small chance of stepping on a patent and blowing you up.” The very notion of seventeen years of patent protection in the fast moving software industry seems absurd. MS-DOS did not exist seventeen years ago.
IP law faces the additional wrinkle of jurisdictional issues. Where has an Internet crime taken place? In the country or state in which the computer server resides? Many nations do not have the same intellectual property laws as the U.S. Even within the U.S., the law can be tough to enforce; for example, a group of music publishers sued CompuServe for the digital distribution of copyrighted music. A complication is that CompuServe has no knowledge of the activity since it occurs in the flood of bits transferring between its subscribers
The tension seen in making digital copies revolves around the issue of property. But unlike the theft of material goods, copying does not deprive the owner of their possessions. With digital piracy, it is less a clear ethical issue of theft, and more an abstract notion that you are undermining the business model of an artist or software developer. The distinction between ethics and laws often revolves around their enforceability. Before copy machines, it was hard to make a book, and so it was obvious and visible if someone was copying your work. In the digital age, copying is lightning fast and difficult to detect. Given ethical ambiguity, convenience, and anonymity, it is no wonder we see a cultural shift with regard to digital ethics.
Piracy, Plagiarism and Pilfering
We copy music. We are seldom diligent with our footnotes. We wonder where we’ve seen Strat-man’s PIE and the four slices before. We forward e-mail that may contain text from a copyrighted news publication. The SCBA estimates that 51% of satellite dishes have illegal descramblers. John Perry Barlow estimates that 90% of personal hard drives have some pirated software on them.
Or as last month’s Red Herring editorial points out, “this atmosphere of electronic piracy seems to have in turn spawned a freer attitude than ever toward good old-fashioned plagiarism.” Articles from major publications and WSJ columns appear and circulate widely on the Internet. Computer Pictures magazine replicated a complete article on multimedia databases from New Media magazine, and then publicly apologized.
Music and voice samples are an increasingly common art form, from 2 Live Crew to Negativland to local bands like Voice Farm and Consolidated. Peter Gabriel embraces the shift to repositioned content; “Traditionally, the artist has been the final arbiter of his work. He delivered it and it stood on its own. In the interactive world, artists will also be the suppliers of information and collage material, which people can either accept as is, or manipulate to create their own art. It’s part of the shift from skill-based work to decision-making and editing work.”
But many traditionalists resist the change. Museums are hesitant to embrace digital art because it is impossible to distinguish the original from a copy; according to a curator at the New Museum of Contemporary Art, “The art world is scared to death of this stuff.” The Digital Audio Tape debate also illustrated the paranoia; the music industry first insisted that these DAT recorders had to purposely introduce static into the digital copies they made, and then they settled for an embedded code that limited the number of successive copies that could be made from the a master source.
For a healthier reaction, look at the phenomenally successful business models of Mosaic/Netscape and Id Software, the twisted creator of Doom. Just as McAfee built a business on shareware, Netscape and Id encourage widespread free distribution of their product. But once you want support from Netscape, or the higher levels of the Doom game, then you have to pay. For industries with strong demand-side economies of scale, such as Netscape web browsers or Safe-TCL intelligent agents, the creators have exploited the economies of information distribution. Software products are especially susceptible to increasing returns with scale, as are networking products and most of the information technology industries.
Yet, the Software Publishers Association reports that 1993 worldwide losses to piracy of business application software totaled $7.45 billion. They also estimated that 89% of software units in Korea were counterfeit. And China has 29 factories, some state-owned, that press 75 million pirated CDs per year, largely for export. GATT will impose the U.S. notions of intellectual property on a world that sees the issue very differently.
Clearly there are strong economic incentives to protect intellectual property, and reasonable arguments can be made for software patents and digital copyright, but the complexities of legal enforcement will be outrun and potentially obviated by the relatively rapid developments of another technology, digital cash and cryptography.
Digital Cash and the IP Lock
Digital cash is in some ways an extreme example of digital “property” -- since it cannot be copied, it is possessed by one entity at a time, and it is static and non-perishable. If the techniques for protecting against pilferage and piracy work in the domain of cash, then they can be used to “protect” other properties by being embedded in them. If I wanted to copy-protect an “original” work of digital art, digital cash techniques can be used as the “container” to protect intellectual property in the old style. A bullet-proof digital cash scheme would inevitably be adapted by those who stand to gain from the current system. Such as Bill Gates.
Several companies are developing technologies for electronic commerce. On January 12, several High-Tech Club members attended the Cybermania conference on electronic commerce with the CEOs of Intuit, CyberCash, Enter TV and The Lightspan Partnership. According to Scott Cook, CEO of Intuit, the motivations for digital cash are anonymity and efficient small-transaction Internet commerce. Anonymity preserves our privacy in the age of increasingly intrusive “database marketing” based on credit card purchase patterns and other personal information. Of course, it also has tax-evasion implications. For Internet commerce, cash is more efficient and easier to use than a credit card for small transactions.
“A lot of people will spend nickels on the Internet,” says Dan Lynch of CyberCash. Banks will soon exchange your current cash for cyber-tokens, or a “bag of bits” which you can spend freely on the Internet. A competitor based in the Netherlands called DigiCash has a Web page with numerous articles on electronic money and fully functional demo of their technology. You can get some free cash from them and spend it at some of their allied vendors.
Digital cash is a compelling technology. Wired magazine calls it the “killer application for electronic networks which will change the global economy.” Handling and fraud costs for the paper money system are growing as digital color copiers and ATMs proliferate. Donald Gleason, President of the Smart Card Enterprise unit of Electronic Payment Services argues that “Cash is a nightmare. It costs money handlers in the U.S. alone approximately $60 billion a year to move the stuff... Bills and coinage will increasingly be replaced by some sort of electronic equivalent.” Even a Citibank VP, Sholom Rosen, agrees that “There are going to be winners and losers, but everybody is going to play.”
The digital cash schemes use a blind digital signature and a central repository to protect against piracy and privacy violations. On the privacy issue, the techniques used have been mathematically proven to be protected against privacy violations. The bank cannot trace how the cash is being used or who is using it. Embedded in these schemes are powerful digital cryptography techniques which have recently been spread in the commercial domain (RSA Data Security is a leader in this field and will be speaking to the High Tech Club on January 19).
To protect against piracy requires some extra work. As soon as I have a digital $5 bill on my Mac hard drive, I will want to make a copy, and I can. (Many companies have busted their picks trying to copy protect files from hackers. It will never work.). The difference is that I can only spend the $5 bill once. The copy is worthless. This is possible because every bill has a unique encrypted identifier. In spending the bill, my computer checks with the centralized repository which verifies that my particular $5 bill is still unspent. Once I spend it, it cannot be spent again. As with many electronic transactions today, the safety of the system depends on the integrity of a centralized computer, or what Dan Lynch calls “the big database in the sky.”
One of the most important limitations of the digital cash techniques is that they are tethered to a transaction between at least three parties — a buyer, seller and central repository. So, to use such a scheme to protect intellectual property, would require networked computers and “live” files that have to dial up and check in with the repository to be operational. There are many compelling applications for this, including voter registration, voting tabulation, and the registration of digital artwork originals.
When I asked Dan Lynch about the use of his technology for intellectual property protection, he agreed that the bits that now represent a $5 bill could be used for any number of things, from medical records to photographs. A digital photograph could hide a digital signature in its low-order bits, and it would be imperceptible to the user. But those bits could be used with a registry of proper image owners, and could be used to prove misappropriation or sampling of the image by others.
Technology author Steven Levy has been researching cryptography for Wired magazine, and he responded to my e-mail questions with the reply “You are on the right track in thinking that crypto can preserve IP. I know of several attempts to forward plans to do so.” Digital cash may provide a “crypto-container” to preserve traditional notions of intellectual property.
The transaction tether limits the short-term applicability of these schemes for software copy protection. They won’t work on an isolated computer. This certainly would slow its adoption for mobile computers since the wireless networking infrastructure is so nascent. But with Windows ’95 bundling network connectivity, soon most computers will be network-ready — at least for the Microsoft network. And now that Bill Gates is acquiring Intuit, instead of dollar bills, we will have Bill dollars.
The transaction tether is also a logistical headache with current slow networks, which may hinder its adoption for mass-market applications. For example, if someone forwards a copyrighted e-mail, the recipient may have to have their computer do the repository check before they could see the text of the e-mail. E-mail is slow enough today, but in the near future, these techniques of verifying IP permissions and paying appropriate royalties in digital cash could be background processes on a preemptive multitasking computer (Windows ’95 or Mac OS System 8). The digital cash schemes are consistent with other trends in software distribution and development — specifically software rental and object-oriented “applets” with nested royalty payments. They are also consistent with the document-centric vision of Open Doc and OLE.
The user of the future would start working on their stationary. When it’s clear they are doing some text entry, the word processor would be downloaded and rented for its current usage. Digital pennies would trickle back to the people who wrote or inspired the various portions of the core program. As you use other software applets, such as a spell-checker, it would be downloaded as needed. By renting applets, or potentially finer-grained software objects, the licensing royalties would be automatically tabulated and exchanged, and software piracy would require heroic efforts. Intellectual property would become precisely that — property in a market economy, under lock by its “creator,” and Bill Gates’ 1975 lament over software piracy may now be addressed 20 years later.
--------end of paper-----------
2013 & 2021 update: On further reflection, I was focused on executable code (where the runtime requires a cloud connect to authenticate, given the third party element of Digicash. (The blockchain fixed this). Verification has been a pain, but perhaps it's seamless in a web-services future. Cloud apps and digital cash depend on it, so why not the code itself.
It could verify the official owner of any unique bundle of pixels, in the sense that you can "own" a sufficiently large number, but not the essence of a work of art or derivative works (what we call NFTs today). Frankly, I'm not sure about non-interactive content in general, like pure video playback. "Fixing" software IP alone would be a big enough accomplishment.
I took this photo of the latest hot lot of processor chips of various sizes at the spook shop summit (InQTel CEO Summit). Pretty shiny bling.
I am in the D-Wave board meeting now, and we just got a peek of next week's TIME Magazine cover (below). And it made the Charlie Rose show.
Here are some excerpts:
"The Quantum Quest for a Revolutionary Computer
The D-Wave Two is an unusual computer, and D-Wave is an unusual company. It's small, just 114 people, and its location puts it well outside the swim of Silicon Valley. But its investors include the storied Menlo Park, Calif., venture-capital firm Draper Fisher Jurvetson, which funded Skype and Tesla Motors. It's also backed by famously prescient Amazon founder Jeff Bezos and an outfit called In-Q-Tel, better known as the high-tech investment arm of the CIA. Likewise, D-Wave has very few customers, but they're blue-chip: they include the defense contractor Lockheed Martin; a computing lab that's hosted by NASA and largely funded by Google; and a U.S. intelligence agency that D-Wave executives decline to name.
The reason D-Wave has so few customers is that it makes a new type of computer called a quantum computer that's so radical and strange, people are still trying to figure out what it's for and how to use it. It could represent an enormous new source of computing power--it has the potential to solve problems that would take conventional computers centuries, with revolutionary consequences for fields ranging from cryptography to nanotechnology, pharmaceuticals to artificial intelligence.
That's the theory, anyway. Some critics, many of them bearing Ph.D.s and significant academic reputations, think D-Wave's machines aren't quantum computers at all. But D-Wave's customers buy them anyway, for around $10 million a pop, because if they're the real deal they could be the biggest leap forward since the invention of the microprocessor. …
Physicist David Deutsch once described quantum computing as "the first technology that allows useful tasks to be performed in collaboration between parallel universes." Not only is this excitingly weird, it's also incredibly useful. If a single quantum bit (or as they're inevitably called, qubits, pronounced cubits) can be in two states at the same time, it can perform two calculations at the same time. Two quantum bits could perform four simultaneous calculations; three quantum bits could perform eight; and so on. The power grows exponentially.
The supercooled niobium chip at the heart of the D-Wave Two has 512 qubits and therefore could in theory perform 2^512 operations simultaneously. That's more calculations than there are atoms in the universe, by many orders of magnitude. "This is not just a quantitative change," says Colin Williams, D-Wave's director of business development and strategic partnerships, who has a Ph.D. in artificial intelligence and once worked as Stephen Hawking's research assistant at Cambridge. "The kind of physical effects that our machine has access to are simply not available to supercomputers, no matter how big you make them. We're tapping into the fabric of reality in a fundamentally new way, to make a kind of computer that the world has never seen."
Naturally, a lot of people want one. This is the age of Big Data, and we're burying ourselves in information-- search queries, genomes, credit-card purchases, phone records, retail transactions, social media, geological surveys, climate data, surveillance videos, movie recommendations--and D-Wave just happens to be selling a very shiny new shovel. "Who knows what hedge-fund managers would do with one of these and the black-swan event that that might entail?" says Steve Jurvetson, one of the managing directors of Draper Fisher Jurvetson. "For many of the computational traders, it's an arms race."
One of the documents leaked by Edward Snowden, published last month, revealed that the NSA has an $80 million quantum-computing project suggestively code-named Penetrating Hard Targets. Here's why: much of the encryption used online is based on the fact that it can take conventional computers years to find the factors of a number that is the product of two large primes. A quantum computer could do it so fast that it would render a lot of encryption obsolete overnight. You can see why the NSA would take an interest. …
For its first five years, the company existed as a think tank focused on research. Draper Fisher Jurvetson got onboard in 2003, viewing the business as a very sexy but very long shot. "I would put it in the same bucket as SpaceX and Tesla Motors," Jurvetson says, "where even the CEO Elon Musk will tell you that failure was the most likely outcome." By then Rose was ready to go from thinking about quantum computers to trying to build them--"we switched from a patent, IP, science aggregator to an engineering company," he says. Rose wasn't interested in expensive, fragile laboratory experiments; he wanted to build machines big enough to handle significant computing tasks and cheap and robust enough to be manufactured commercially. With that in mind, he and his colleagues made an important and still controversial decision.
Up until then, most quantum computers followed something called the gate-model approach, which is roughly analogous to the way conventional computers work, if you substitute qubits for transistors. But one of the things Rose had figured out in those early years was that building a gate-model quantum computer of any useful size just wasn't going to be feasible anytime soon. …
Adiabatic quantum computing may be technically simpler than the gate-model kind, but it comes with trade-offs. An adiabatic quantum computer can really solve only one class of problems, called discrete combinatorial optimization problems, which involve finding the best--the shortest, or the fastest, or the cheapest, or the most efficient--way of doing a given task.
This is great if you have a really hard discrete combinatorial optimization problem to solve. Not everybody does. But once you start looking for optimization problems, or at least problems that can be twisted around to look like optimization problems, you find them all over the place: in software design, tumor treatments, logistical planning, the stock market, airline schedules, the search for Earth-like planets in other solar systems, and in particular in machine learning.
Google and NASA, along with the Universities Space Research Association, jointly run something called the Quantum Artificial Intelligence Laboratory, or QuAIL, based at NASA Ames, which is the proud owner of a D-Wave Two. "If you're trying to do planning and scheduling for how you navigate the Curiosity rover on Mars or how you schedule the activities of astronauts on the station, these are clearly problems where a quantum computer--a computer that can optimally solve optimization problems--would be useful," says Rupak Biswas, deputy director of the Exploration Technology Directorate at NASA Ames. Google has been using its D-Wave to, among other things, write software that helps Google Glass tell the difference between when you're blinking and when you're winking.
Lockheed Martin turned out to have some optimization problems too. It produces a colossal amount of computer code, all of which has to be verified and validated for all possible scenarios, lest your F-35 spontaneously decide to reboot itself in midair. "It's very difficult to exhaustively test all of the possible conditions that can occur in the life of a system," says Ray Johnson, Lockheed Martin's chief technology officer. "Because of the ability to handle multiple conditions at one time through superposition, you're able to much more rapidly--orders of magnitude more rapidly--exhaustively test the conditions in that software." The company re-upped for a D-Wave Two last year.
Another challenge Rose and company face is that there is a small but nonzero number of academic physicists and computer scientists who think that they are partly or completely full of sh-t. Ever since D-Wave's first demo in 2007, snide humor, polite skepticism, impolite skepticism and outright debunkings have been lobbed at the company from any number of ivory towers. "There are many who in Round 1 of this started trash-talking D-Wave before they'd ever met the company," Jurvetson says. "Just the mere notion that someone is going to be building and shipping a quantum computer--they said, 'They are lying, and it's smoke and mirrors.'"
Seven years and many demos and papers later, the company isn't any less controversial. Any blog post or news story about D-Wave instantly grows a shaggy beard of vehement comments, both pro- and anti-. …
But where quantum computing is concerned, there always seems to be room for disagreement. Hartmut Neven, the director of engineering who runs Google's quantum-computing project, argues that the tests weren't a failure at all--that in one class of problem, the D-Wave Two outperformed the classical computers in a way that suggests quantum effects were in play. "There you see essentially what we were after," he says. "There you see an exponentially widening gap between simulated annealing and quantum annealing ... That's great news, but so far nobody has paid attention to it." Meanwhile, two other papers published in January make the case that a) D-Wave's chip does demonstrate entanglement and b) the test used the wrong kind of problem and was therefore meaningless anyway. For now pretty much everybody at least agrees that it's impressive that a chip as radically new as D-Wave's could even achieve parity with conventional hardware.
The attitude in D-Wave's C-suite toward all this back-and-forth is, unsurprisingly, dismissive. "The people that really understand what we're doing aren't skeptical," says Brownell. Rose is equally calm about it; all that wrestling must have left him with a thick skin. "Unfortunately," he says, "like all discourse on the Internet, it tends to be driven by a small number of people that are both vocal and not necessarily the most informed." He's content to let the products prove themselves, or not. "It's fine," he says. "It's good. Science progresses by rocking the ship. Things like this are a necessary component of forward progress."
Are D-Wave's machines quantum computers?
For now the answer is itself suspended, aptly enough, in a state of superposition, somewhere between yes and no. If the machines can do anything like what D-Wave is predicting, they won't leave many fields untouched. "I think we'll look back on the first time a quantum computer outperformed classical computing as a historic milestone," Brownell says. "It's a little grand, but we're kind of like Intel and Microsoft in 1977, at the dawn of a new computing era."
Michele Reilly is a scientist, an artist, and a systems thinker whose work resists easy classification. She trained in architecture and art at Cooper Union, where she began building intelligent machines and quickly became fascinated by the logic behind them. That curiosity drew her into mathematics, cryptography, macroeconomics, and eventually quantum physics. Her path has been shaped less by credentials than by the depth of her questions.
At MIT, where she teaches in the Department of Mechanical Engineering, Michele works at the intersection of computation and the structure of spacetime. She explores how information flows through the universe, drawing from Claude Shannon’s foundational theories and extending them into the quantum realm. Her research is ambitious, but it is rooted in careful thinking. She is not interested in speculation for its own sake. She wants to know what can be built, what can be measured, and what will last.
In 2016, she co-founded Turing, a quantum technology startup focused on building portable quantum memories and tools for long-distance quantum communication. She works closely with physicist Seth Lloyd on designing the scalable, robust systems needed to move quantum computing from theory into practice. The work is intricate and deliberate, building slowly toward a future that she sees as both beautiful and unfamiliar.
Michele is also a storyteller. Her science fiction series Steeplechase has received awards at Cannes and other international festivals. It reflects her belief that narrative and science are not separate pursuits, but parallel ways of exploring the unknown. In her teaching, she brings these strands together, guiding students through exercises that combine quantum theory, creative writing, and world-building. One of her courses, supported by MIT’s Center for Art, Science and Technology, invites students to imagine speculative futures grounded in scientific inquiry.
On her arm is a tattoo of Alan Turing. It is not ornamental. It is a quiet tribute to a thinker whose life and work continue to shape her own. Turing’s dedication to truth, structure, and the ethical weight of technology is a constant presence in her thinking. She carries it with her, quite literally.
The portrait above was made at The Interval at the Long Now Foundation in San Francisco. Michele is seated beside a polished table that reflects her image. Behind her stands the Orrery, a planetary model designed to keep time for ten thousand years. The setting reflects the spirit of her work. She is grounded in the present but always thinking forward, asking how we might live in ways that honor complexity, care, and continuity. She does not speak often about legacy. She speaks about attention, about precision, and about the discipline of staying with difficult questions until they begin to yield something real.
Michele Reilly is a scientist, an artist, and a systems thinker whose work resists easy classification. She trained in architecture and art at Cooper Union, where she began building intelligent machines and quickly became fascinated by the logic behind them. That curiosity drew her into mathematics, cryptography, macroeconomics, and eventually quantum physics. Her path has been shaped less by credentials than by the depth of her questions.
At MIT, where she teaches in the Department of Mechanical Engineering, Michele works at the intersection of computation and the structure of spacetime. She explores how information flows through the universe, drawing from Claude Shannon’s foundational theories and extending them into the quantum realm. Her research is ambitious, but it is rooted in careful thinking. She is not interested in speculation for its own sake. She wants to know what can be built, what can be measured, and what will last.
In 2016, she co-founded Turing, a quantum technology startup focused on building portable quantum memories and tools for long-distance quantum communication. She works closely with physicist Seth Lloyd on designing the scalable, robust systems needed to move quantum computing from theory into practice. The work is intricate and deliberate, building slowly toward a future that she sees as both beautiful and unfamiliar.
Michele is also a storyteller. Her science fiction series Steeplechase has received awards at Cannes and other international festivals. It reflects her belief that narrative and science are not separate pursuits, but parallel ways of exploring the unknown. In her teaching, she brings these strands together, guiding students through exercises that combine quantum theory, creative writing, and world-building. One of her courses, supported by MIT’s Center for Art, Science and Technology, invites students to imagine speculative futures grounded in scientific inquiry.
On her arm is a tattoo of Alan Turing. It is not ornamental. It is a quiet tribute to a thinker whose life and work continue to shape her own. Turing’s dedication to truth, structure, and the ethical weight of technology is a constant presence in her thinking. She carries it with her, quite literally.
The portrait above was made at The Interval at the Long Now Foundation in San Francisco. Michele is seated beside a polished table that reflects her image. Behind her stands the Orrery, a planetary model designed to keep time for ten thousand years. The setting reflects the spirit of her work. She is grounded in the present but always thinking forward, asking how we might live in ways that honor complexity, care, and continuity. She does not speak often about legacy. She speaks about attention, about precision, and about the discipline of staying with difficult questions until they begin to yield something real.
Cryptography Furnace.
Αδιάφορος μέσα πραγματικότητες εγκαύματα αυστηρή ιδιότητες καθολικότητα του,
idem quod quid sensuale, et determinante constituta mobilitate carbones,
inventions probablement arrogance carnaval préoccupations mécontents feux allumés abandonnés,
natychmiastowa operacja twierdząc mylące chwile głosy absurdalne,
فزعا حرق العيون المتحجرة تواجه يحتقر مدوية تتدفق الحمم,
sallied farw coch oren llosgi dagrau pwysau gwag euraidd cornwydydd,
smiing fjell steiner polert sirkler noen gang snur,
fundamentale ius calidum malum profundum amplitudine possessiones descendentem,
interpretaciones silenciosos elevación más sabio de la rodilla,
óriási commencements heves államférfiak tartozik,
zagregowane szkoleniami ustalenia niematerialne Postępy liczne obr,
erkend individualisme's terugtrekkende bewustzijn bereiken contingenten stijgen,
астигматизма стада покой поддержания обычные законы боится,
愚かな派手な聖化の誤解の宣誓供述書は、カリカリ焼け!
Steve.D.Hammond.
When one hears the words, “stealth ship” it’s easy to get excited. Imagine our excitement when I saw the first one known to exist, abandoned, decaying, rusting away in front of my own eyes. Though this ship was small, at 164 feet from bow to stern, I couldn’t believe that we had infiltrated the row of the Mothball Fleet in Suisun Bay that held the IX-529 Sea Shadow. Perhaps more interesting than the Sea Shadow itself was the drydock it was ensconced within: HMB-1, the Hughes Mining Barge, built by the famed Howard Hughes company for the CIA in the early 1970s. HMB-1 was one part of a two-part structure used to lift the sunken nuclear Russian submarine, K-129, from the ocean Northwest of Hawaii. K-129 was 16,000 feet underwater, so Hughes built the Glomar Explorer, ostensibly as a Manganese mining ship. The real purpose of the Hughes Mining Barge was to submerge and serve as a purpose-built submerged (and hidden) drydock for any remains recovered from the submarine wreck site (including cryptographic code books, secret intelligence from the Soviet Navy, and nuclear munitions); the Glomar Explorer on the other hand, served as the cover story (manganese nodule mining) and as the powerhouse for lifting the gigantic, 2700-ton submarine from the depths of the ocean.
In the end, Clementine, the gigantic claw that was used to lift the submarine failed; the submarine split in half. Most of the important intelligence was lost in the process, and “Project Jennie,” as it was erroneously known by the press, was a failure. By 1983, HMB-1 was mothballed, but it oddly disappeared from Todd Shipyards, where it was being stored. Inquiries from the press reached a dead end – the only thing the Navy could say was that it wasn’t being used to lift a submarine from the water. The real story was that HMB-1 housed the top secret stealth ship, Sea Shadow IX-529. The Sea Shadow was dismantled in 2012, but HMB-1 still exists in Alameda.
Nobel Prize in physics awarded for breakthroughs in quantum mechanics
By Joel Achenbach
Updated October 4, 2022 at 8:05 a.m. EDT|Published October 4, 2022 at 6:17 a.m. EDT
0:36 / 1:04
Physicists John F. Clauser, Alain Aspect and Anton Zeilinger received the 2022 Nobel Prize in physics on Oct. 4, for their research in quantum mechanics. (Video: AP)
The 2022 Nobel Prize in physics has been awarded to three physicists for their pioneering experiments in quantum information science, a burgeoning field that could revolutionize computing, cryptography and the transfer of information via what is known as “quantum teleportation.”
John F. Clauser, 79, an American physicist in Walnut Creek, Calif., was laureated along with Alain Aspect of Université Paris-Saclay and École Polytechnique in France and Anton Zeilinger of the University of Vienna in Austria.
“It was very kind to receive your phone call just about an hour ago. I’m still kind of shocked,” Zeilinger said in an interview conducted during the news conference at the Royal Swedish Academy of Sciences, which awards the Nobels.
When asked by a reporter if, in 10,000 years, it will be possible to teleport one’s own body to another place, he answered that the teleportation of people is “science fiction.”
Quantum mechanics is an area of physics going back more than a century, and has already yielded applications that people use in everyday life, from transistors to lasers. But the potential applications of the principles of quantum mechanics appear limitless.
The physicists honored Tuesday found ways to confirm what had been previously theorized, including the “entanglement” of photons (particles of light).
In a press release, the Academy explained the phenomenon, which Albert Einstein famously referred to as “spooky action at a distance”: “What happens to one particle in an entangled pair determines what happens to the other, even if they are really too far apart to affect each other. The laureates’ development of experimental tools has laid the foundation for a new era of quantum technology.”
The experiments in quantum entanglement cited by the Academy began more than half a century ago. In 1972, Clauser and a colleague, Stuart Freedman — who died in 2012 — used an apparatus that emitted two entangled photons in a manner consistent with predictions of quantum mechanics, according to the Academy. As a French doctoral student, Aspect improved the efficiency of the experiments and the clarity of the results, and Zeilinger then explored systems that used more than two entangled particles, the Academy explained.
“These experiments have probed the very foundations of the quantum world, and have brought into focus the most striking and challenging aspects of quantum physics,” physicist Stephen Bartlett of the University of Sydney and the lead editor of the American Physical Society’s quantum journal, said Tuesday by email. “Specifically, they demonstrate that ‘entangled’ quantum particles behave in a way completely at odds with our notions of how independent, separate objects should behave.”
Asked after the news conference in Stockholm about the meaning of quantum mechanics, Thors Hans Hansson, a theoretical physicist and member of the Nobel committee for physics, told reporters, “That is something you never get finished with. You always wonder what is it, how do you understand it and you try to go deeper and deeper into it.”
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The Academy’s physics prize tends to rotate through the many disciplines within the sprawling physics enterprise, which covers everything from subatomic particles to the origin of the universe. Last year the prize focused on climate change, with the prize going to Syukuro Manabe of the United States and Klaus Hasselmann of Germany for research on the human influence on climate, and to Giorgio Parisi, an Italian theorist whose work described fluctuating systems at different physical scales.
In 2020, black holes were the focus of the Academy, which awarded prizes to American astrophysicists Andrea Ghez of the United States and Reinhard Genzel of Germany, as well as the British mathematical physicist Roger Penrose.
This is a developing story. It will be updated.
Calcite, Paint
Thebes, Valley of the Kings, Tomb of Tutankhamun (KV 62).
New Kingdom, 18th Dynasty, Reign of Tutankhamun (1355-1346 BCE).
Tutankhamun's tomb held more than eighty vessels of oils and unguents, but thieves stole most of the contents. This container has a central frieze in which the royal throne name appears in a cryptographic writing, ensuring the survival of the king's name.
King Tut exhibit, Seattle Washington, 2012.
monica trenkler . . . . . . . . . . . . . . . . . . . . . . .
handmade collage on cardboard
50 x 35 cm
A Lockheed Martin F-22 "Raptor" flies behind a Boeing KC-135 "Stratotanker" during aerial refueling training off the coast of Finland, Oct 19, 2018. The F-22 deployed from the 27th Fighter Squadron, Joint Base Langley-Eustis, Va.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 "Flanker"- and MiG-29 "Fulcrum"-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler.[60] Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP).[66] A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D.[83][84] To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
Alan Turing (1912-54) was an English mathematician, logician, cryptanalyst and computer scientist of dazzling ability. He was highly influential in the development of computer science and is widely considered to be the father of both computer science and artificial intelligence.
More than that, perhaps, during the Second World War he and his team broke the code of the highly complex Enigma and Lorenz cipher machines, which kept German military and strategic communications secret. This meticulous, painstaking work was done at Bletchley Park, Britain’s code-breaking centre. After the war he worked at the National Physical Laboratory in Teddington, where he created one of the first designs for a stored-program computer, the ACE.
Alan Turing was gay, and was prosecuted in 1952, when homosexual acts (even between adults in private, as in his case) were illegal in the UK. This conviction resulted in his security clearance being removed, and despite his acknowledged brilliance he was barred from continuing with his cryptographic work for GCHQ. He committed suicide in 1954 at the age of 41. Fifty-five years later, in 2009, the British government formally apologised for the way in which he was treated after the war; and in 2013 he received a long overdue royal pardon.
This is a detail from an outstanding life-size sculpture in half a million pieces of slate by Stephen Kettle. It's to be found in the Block B museum at Bletchley Park, near Milton Keynes. Oh, and that's a portrait of Alan Turing in the background. Two heroes for the price of one.
View on black - it looks good.
Cyber security is strongest when engineered into our systems versus designing cyber security protections later. That is why we design all aircraft, and their supporting systems, to operate in a cyber contested environment.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 "Raptor" is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 "Eagle" and F-16 "Fighting Falcon". Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 "Flanker"- and MiG-29 "Fulcrum"-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 "Eagle" and F-16 "Fighting Falcon" or the newer F-35 "Lightning II", which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G "Growler". Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP).[66] A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D. To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 "Raptor" is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 "Phantom II" that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
Entered production as the Lockheed Martin F-22 'Raptor".
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 "Flanker"- and MiG-29 "Fulcrum"-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler.[60] Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP).[66] A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D.[83][84] To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
Happy Pi Day everyone!
P versus NP problem is one of most important unsolved problem in mathematics, more specifically in computer science. You might think the problem have nothing to do with everyday life for us, but it actually has giant impact depends on how it concludes. If this problem would concludes P = NP then, almost of all cryptography method can be broken using the conclusion. Which means you no longer can send password or credit card information safely. But if it concludes P ≠ NP then nothing would happen in our everyday life but it proofs that cryptography we use everyday(SSL) on the internet is really safe. In another words, the cryptography algorithms we use everyday haven't been proofed that they are really safe to use, but most experts think that cryptography algorithms are safe because anyone haven't found any algorithm to break them. But it is just what they believe, not what have been proofed formally. So this problem is the most interesting problem for me. Wishing this problem would be solved near future, hopefully while I'm living.
3月14日はπの日です。
P≠NP予想は数学（より正確には計算機科学）での未解決問題のうち最も重要な問題のうちのひとつです。何か難しそうな問題がどうなろうと私たちの日常には全く関係ないと思われるかもしれませんが、実は関係大有りなのです。もし、この問題がP = NPと証明された場合、その結果を使ってインターネット上で使われているほぼ全ての暗号を解くことが可能になります。つまり、安全にパスワードやクレジットカード情報を送ることができなくなります。しかし、もしP ≠ NPと証明された場合、インターネット上の暗号は本当に安全であると証明されます。言い換えると、今インターネット上でセキュリティを確保するために使われている暗号は、その解読方法が見つけられていないために大半の専門家が安全であると信じていますが、本当に安全であるかどうか厳密に検証されたわけではないということです。ということで、この問題は私が最も興味のある問題です。願わくば私が生きているうちに証明されて欲しいものです。
[ Nikon D4, Nikon AF-S NIKKOR 50mm f/1.4G, f/4.0, 1/50sec, ISO500, SB-910 AF Speedlight, Lightroom 5 ]
A U.S. Air Force Lockheed Martin F-22 Raptor assigned to the 90th Fighter Squadron approaches a U.S. Air Force Boeing KC-135 Stratotanker in order to receive fuel in the skies above Royal Australian Air Force Base Tindal, Australia, March 2, 2017. Twelve Lockheed Martin F-22 Raptors and approximately 200 U.S. Air Force Airmen participated in the first Enhanced Air Cooperation, an initiative under the Force Posture Agreement between the U.S. and Australia.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 Flanker and MiG-29 Fulcrum-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler. Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP). A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D. To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.
A Royal Air Force Lockheed Martin F-35 "Lightning II", U.S. Air Force Boeing F-15E "Strike Eagle", and French air force Dassault "Rafale" fly behind a U.S. Air Force Boeing KC-135 "Stratotanker" from the 100th Air Refueling Wing during Exercise Point Blank over the English Channel, Nov. 27, 2018. Training with NATO allies like the U.K. and France improves interoperability and demonstrates the United States’ commitment to regional security. Exercise Point Blank also represents an opportunity to enhance interoperability and integration between allied fourth and fifth-generation fighter aircraft.
From Wikipedia, the free encyclopedia
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter (ATF) program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. Despite its protracted development and various operational issues, USAF officials consider the F-22 a critical component of the service's tactical air power. Its combination of stealth, aerodynamic performance, and situational awareness enable unprecedented air combat capabilities.
Service officials had originally planned to buy a total of 750 ATFs. In 2009, the program was cut to 187 operational production aircraft due to high costs, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35. The last F-22 was delivered in 2012.
Development
Origins
In 1981, the U.S. Air Force identified a requirement for an Advanced Tactical Fighter (ATF) to replace the F-15 Eagle and F-16 Fighting Falcon. Code named "Senior Sky", this air-superiority fighter program was influenced by emerging worldwide threats, including new developments in Soviet air defense systems and the proliferation of the Su-27 "Flanker"- and MiG-29 "Fulcrum"-class of fighter aircraft. It would take advantage of the new technologies in fighter design on the horizon, including composite materials, lightweight alloys, advanced flight control systems, more powerful propulsion systems, and most importantly, stealth technology. In 1983, the ATF concept development team became the System Program Office (SPO) and managed the program at Wright-Patterson Air Force Base. The demonstration and validation (Dem/Val) request for proposals (RFP) was issued in September 1985, with requirements placing strong emphasis on stealth and supercruise. Of the seven bidding companies, Lockheed and Northrop were selected on 31 October 1986. Lockheed teamed with Boeing and General Dynamics while Northrop teamed with McDonnell Douglas, and the two contractor teams undertook a 50-month Dem/Val phase, culminating in the flight test of two technology demonstrator prototypes, the YF-22 and the YF-23, respectively.
Dem/Val was focused on risk reduction and technology development plans over specific aircraft designs. Contractors made extensive use of analytical and empirical methods, including computational fluid dynamics, wind-tunnel testing, and radar cross-section calculations and pole testing; the Lockheed team would conduct nearly 18,000 hours of wind-tunnel testing. Avionics development was marked by extensive testing and prototyping and supported by ground and flying laboratories. During Dem/Val, the SPO used the results of performance and cost trade studies conducted by contractor teams to adjust ATF requirements and delete ones that were significant weight and cost drivers while having marginal value. The short takeoff and landing (STOL) requirement was relaxed in order to delete thrust-reversers, saving substantial weight. As avionics was a major cost driver, side-looking radars were deleted, and the dedicated infra-red search and track (IRST) system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components. The ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. Despite efforts by the contractor teams to rein in weight, the takeoff gross weight estimate was increased from 50,000 lb (22,700 kg) to 60,000 lb (27,200 kg), resulting in engine thrust requirement increasing from 30,000 lbf (133 kN) to 35,000 lbf (156 kN) class.
Each team produced two prototype air vehicles for Dem/Val, one for each of the two engine options. The YF-22 had its maiden flight on 29 September 1990 and in flight tests achieved up to Mach 1.58 in supercruise. After the Dem/Val flight test of the prototypes, on 23 April 1991, Secretary of the USAF Donald Rice announced the Lockheed team as the winner of the ATF competition. The YF-23 design was considered stealthier and faster, while the YF-22, with its thrust vectoring nozzles, was more maneuverable as well as less expensive and risky. The aviation press speculated that the Lockheed team's design was also more adaptable to the U.S. Navy's Navalized Advanced Tactical Fighter (NATF), but by 1992, the Navy had abandoned NATF.
Production and procurement
As the program moved to full-scale development, or the Engineering & Manufacturing Development (EMD) stage, the production version had notable differences from the YF-22, despite having a broadly similar shape. The swept-back angle of the leading edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward and decreased in area by 20%. To improve pilot visibility, the canopy was moved forward 7 inches (18 cm), and the engine intakes moved rearward 14 inches (36 cm). The shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and maneuver performance.
Prime contractor Lockheed Martin Aeronautics manufactured the majority of the airframe and performed final assembly at Dobbins Air Reserve Base in Marietta, Georgia; program partner Boeing Defense, Space & Security provided additional airframe components as well as avionics integration and training systems. The first F-22, an EMD aircraft with tail number 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. Production, with the first lot awarded in September 2000, supported over 1,000 subcontractors and suppliers from 46 states and up to 95,000 jobs, and spanned 15 years at a peak rate of roughly two airplanes per month. In 2006, the F-22 development team won the Collier Trophy, American aviation's most prestigious award. Due to the aircraft's advanced nature, contractors have been targeted by cyberattacks and technology theft.
The USAF originally envisioned ordering 750 ATFs at a total program cost of $44.3 billion and procurement cost of $26.2 billion in fiscal year (FY) 1985 dollars, with production beginning in 1994. The 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, which was again reduced to 277 by 2003. In 2004, the Department of Defense (DoD) further reduced this to 183 operational aircraft, despite the USAF's preference for 381. A multi-year procurement plan was implemented in 2006 to save $15 billion, with total program cost projected to be $62 billion for 183 F-22s distributed to seven combat squadrons. In 2008, Congress passed a defense spending bill that raised the total orders for production aircraft to 187.
The first two F-22s built were EMD aircraft in the Block 1.0 configuration for initial flight testing, while the third was a Block 2.0 aircraft built to represent the internal structure of production airframes and enabled it to test full flight loads. Six more EMD aircraft were built in the Block 10 configuration for development and upgrade testing, with the last two considered essentially production quality jets. Production for operational squadrons consisted of 37 Block 20 training aircraft and 149 Block 30/35 combat aircraft; one of the Block 35 aircraft is dedicated to flight sciences at Edwards Air Force Base.
The numerous new technologies in the F-22 resulted in substantial cost overruns and delays. Many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. As production wound down in 2011, the total program cost is estimated to be about $67.3 billion, with $32.4 billion spent on Research, Development, Test and Evaluation (RDT&E) and $34.9 billion on procurement and military construction (MILCON) in then year dollars. The incremental cost for an additional F-22 was estimated at about $138 million in 2009.
Ban on exports
The F-22 cannot be exported under US federal law to protect its stealth technology and other high-tech features. Customers for U.S. fighters are acquiring earlier designs such as the F-15 Eagle and F-16 Fighting Falcon or the newer F-35 Lightning II, which contains technology from the F-22 but was designed to be cheaper, more flexible, and available for export. In September 2006, Congress upheld the ban on foreign F-22 sales. Despite the ban, the 2010 defense authorization bill included provisions requiring the DoD to prepare a report on the costs and feasibility for an F-22 export variant, and another report on the effect of F-22 export sales on U.S. aerospace industry.
Some Australian politicians and defense commentators proposed that Australia should attempt to purchase F-22s instead of the planned F-35s, citing the F-22's known capabilities and F-35's delays and developmental uncertainties. However, the Royal Australian Air Force (RAAF) determined that the F-22 was unable to perform the F-35's strike and close air support roles. The Japanese government also showed interest in the F-22 for its Replacement-Fighter program. The Japan Air Self-Defense Force (JASDF) would reportedly require fewer fighters for its mission if it obtained the F-22, thus reducing engineering and staffing costs. However, in 2009 it was reported that acquiring the F-22 would require increases to the Japanese government's defense budget beyond the historical 1 percent of its GDP. With the end of F-22 production, Japan chose the F-35 in December 2011. Israel also expressed interest, but eventually chose the F-35 because of the F-22's price and unavailability.
Production termination
Throughout the 2000s, the need for F-22s was debated, due to rising costs and the lack of relevant adversaries. In 2006, Comptroller General of the United States David Walker found that "the DoD has not demonstrated the need" for more investment in the F-22, and further opposition to the program was expressed by Secretary of Defense Donald Rumsfeld, Deputy Secretary of Defense Gordon R. England, Senator John McCain, and Chairman of U.S. Senate Committee on Armed Services Senator John Warner. The F-22 program lost influential supporters in 2008 after the forced resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley.
In November 2008, Secretary of Defense Robert Gates stated that the F-22 was not relevant in post-Cold War conflicts such as irregular warfare operations in Iraq and Afghanistan, and in April 2009, under the new Obama Administration, he called for ending production in FY2011, leaving the USAF with 187 production aircraft. In July, General James Cartwright, Vice Chairman of the Joint Chiefs of Staff, stated to the Senate Committee on Armed Services his reasons for supporting termination of F-22 production. They included shifting resources to the multirole F-35 to allow proliferation of fifth-generation fighters for three service branches and preserving the F/A-18 production line to maintain the military's electronic warfare (EW) capabilities in the Boeing EA-18G Growler.[60] Issues with the F-22's reliability and availability also raised concerns. After President Obama threatened to veto further production, the Senate voted in July 2009 in favor of ending production and the House subsequently agreed to abide by the 187 production aircraft cap. Gates stated that the decision was taken in light of the F-35's capabilities, and in 2010, he set the F-22 requirement to 187 aircraft by lowering the number of major regional conflict preparations from two to one.
In 2010, USAF initiated a study to determine the costs of retaining F-22 tooling for a future Service Life Extension Program (SLEP).[66] A RAND Corporation paper from this study estimated that restarting production and building an additional 75 F-22s would cost $17 billion, resulting in $227 million per aircraft, or $54 million higher than the flyaway cost. Lockheed Martin stated that restarting the production line itself would cost about $200 million. Production tooling and associated documentation were subsequently stored at the Sierra Army Depot, allowing the retained tooling to support the fleet life cycle. There were reports that attempts to retrieve this tooling found empty containers, but a subsequent audit found that the tooling was stored as expected.
Russian and Chinese fighter developments have fueled concern, and in 2009, General John Corley, head of Air Combat Command, stated that a fleet of 187 F-22s would be inadequate, but Secretary Gates dismissed General Corley's concern. In 2011, Gates explained that Chinese fifth-generation fighter developments had been accounted for when the number of F-22s was set, and that the U.S. would have a considerable advantage in stealth aircraft in 2025, even with F-35 delays. In December 2011, the 195th and final F-22 was completed out of 8 test EMD and 187 operational aircraft produced; the aircraft was delivered to the USAF on 2 May 2012.
In April 2016, the House Armed Services Committee (HASC) Tactical Air and Land Forces Subcommittee proposed legislation that would direct the Air Force to conduct a cost study and assessment associated with resuming production of the F-22. Since the production halt directed in 2009 by then Defense Secretary Gates, lawmakers and the Pentagon noted that air warfare systems of Russia and China were catching up to those of the U.S. Lockheed Martin has proposed upgrading the Block 20 training aircraft into combat-coded Block 30/35 versions as a way to increase numbers available for deployment. On 9 June 2017, the Air Force submitted their report to Congress stating they had no plans to restart the F-22 production line due to economic and operational issues; it estimated it would cost approximately $50 billion to procure 194 additional F-22s at a cost of $206–$216 million per aircraft, including approximately $9.9 billion for non-recurring start-up costs and $40.4 billion for aircraft procurement costs.
Upgrades
The first aircraft with combat-capable Block 3.0 software flew in 2001. Increment 2, the first upgrade program, was implemented in 2005 for Block 20 aircraft onward and enabled the employment of Joint Direct Attack Munitions (JDAM). Certification of the improved AN/APG-77(V)1 radar was completed in March 2007, and airframes from production Lot 5 onward are fitted with this radar, which incorporates air-to-ground modes. Increment 3.1 for Block 30 aircraft onward provided improved ground-attack capability through synthetic aperture radar mapping and radio emitter direction finding, electronic attack and Small Diameter Bomb (SDB) integration; testing began in 2009 and the first upgraded aircraft was delivered in 2011. To address oxygen deprivation issues, F-22s were fitted with an automatic backup oxygen system (ABOS) and modified life support system starting in 2012.
Increment 3.2 for Block 35 aircraft is a two-part upgrade process; 3.2A focuses on electronic warfare, communications and identification, while 3.2B includes geolocation improvements and a new stores management system to show the correct symbols for the AIM-9X and AIM-120D.[83][84] To enable two-way communication with other platforms, the F-22 can use the Battlefield Airborne Communications Node (BACN) as a gateway. The planned Multifunction Advanced Data Link (MADL) integration was cut due to development delays and lack of proliferation among USAF platforms. The F-22 fleet is planned to start receiving Increment 3.2B as well as a software upgrade for cryptography capabilities and avionics stability in May 2019. A Multifunctional Information Distribution System-Joint (MIDS-J) radio that replaces the current Link-16 receive-only box is expected to be operational by 2020. Subsequent upgrades are also focusing on having an open architecture to enable faster future enhancements.
In 2024, funding is projected to begin for the F-22 mid-life upgrade (MLU), which is expected to include new sensors and antennas, hardware refresh, cockpit improvements, and a helmet mounted display and cuing system. Other enhancements being developed include IRST functionality for the AN/AAR-56 Missile Launch Detector (MLD) and more durable stealth coating based on the F-35's.
The F-22 was designed for a service life of 8,000 flight hours, with a $350 million "structures retrofit program". Investigations are being made for upgrades to extend their useful lives further. In the long term, the F-22 is expected to be superseded by a sixth-generation jet fighter to be fielded in the 2030s.
Design
Overview
The F-22 Raptor is a fifth-generation fighter that is considered fourth generation in stealth aircraft technology by the USAF.[91] It is the first operational aircraft to combine supercruise, supermaneuverability, stealth, and sensor fusion in a single weapons platform. The F-22 has four empennage surfaces, retractable tricycle landing gear, and clipped delta wings with reverse trailing edge sweep and leading edge extensions running to the upper outboard corner of the inlets. Flight control surfaces include leading-edge flaps, flaperons, ailerons, rudders on the canted vertical stabilizers, and all-moving horizontal tails (stabilators); for speed brake function, the ailerons deflect up, flaperons down, and rudders outwards to increase drag.
The aircraft's dual Pratt & Whitney F119-PW-100 augmented turbofan engines are closely spaced and incorporate pitch-axis thrust vectoring nozzles with a range of ±20 degrees; each engine has maximum thrust in the 35,000 lbf (156 kN) class. The F-22's thrust-to-weight ratio at typical combat weight is nearly at unity in maximum military power and 1.25 in full afterburner. Maximum speed without external stores is approximately Mach 1.8 at military power and greater than Mach 2 with afterburners.
The F-22's high cruise speed and operating altitude over prior fighters improve the effectiveness of its sensors and weapon systems, and increase survivability against ground defenses such as surface-to-air missiles. The aircraft is among only a few that can supercruise, or sustain supersonic flight without using fuel-inefficient afterburners; it can intercept targets which subsonic aircraft would lack the speed to pursue and an afterburner-dependent aircraft would lack the fuel to reach. The F-22's thrust and aerodynamics enable regular combat speeds of Mach 1.5 at 50,000 feet (15,000 m). The use of internal weapons bays permits the aircraft to maintain comparatively higher performance over most other combat-configured fighters due to a lack of aerodynamic drag from external stores. The aircraft's structure contains a significant amount of high-strength materials to withstand stress and heat of sustained supersonic flight. Respectively, titanium alloys and composites comprise 39% and 24% of the structural weight.
The F-22's aerodynamics, relaxed stability, and powerful thrust-vectoring engines give it excellent maneuverability and energy potential across its flight envelope. The airplane has excellent high alpha (angle of attack) characteristics, capable of flying at trimmed alpha of over 60° while maintaining roll control and performing maneuvers such as the Herbst maneuver (J-turn) and Pugachev's Cobra. The flight control system and full-authority digital engine control (FADEC) make the aircraft highly departure resistant and controllable, thus giving the pilot carefree handling.
Stealth
The F-22 was designed to be highly difficult to detect and track by radar. Measures to reduce radar cross-section (RCS) include airframe shaping such as alignment of edges, fixed-geometry serpentine inlets and curved vanes that prevent line-of-sight of the engine faces and turbines from any exterior view, use of radar-absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. The F-22 was also designed to have decreased radio emissions, infrared signature and acoustic signature as well as reduced visibility to the naked eye. The aircraft's flat thrust-vectoring nozzles reduce infrared emissions of the exhaust plume to mitigate the threat of infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Additional measures to reduce the infrared signature include special topcoat and active cooling of leading edges to manage the heat buildup from supersonic flight.
Compared to previous stealth designs like the F-117, the F-22 is less reliant on RAM, which are maintenance-intensive and susceptible to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. The F-22 has a Signature Assessment System which delivers warnings when the radar signature is degraded and necessitates repair. While the F-22's exact RCS is classified, in 2009 Lockheed Martin released information indicating that from certain angles the aircraft has an RCS of 0.0001 m² or −40 dBsm – equivalent to the radar reflection of a "steel marble". Effectively maintaining the stealth features can decrease the F-22's mission capable rate to 62–70%.
The effectiveness of the stealth characteristics is difficult to gauge. The RCS value is a restrictive measurement of the aircraft's frontal or side area from the perspective of a static radar. When an aircraft maneuvers it exposes a completely different set of angles and surface area, potentially increasing radar observability. Furthermore, the F-22's stealth contouring and radar absorbent materials are chiefly effective against high-frequency radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars such as weather radars and early-warning radars are more likely to detect the F-22 due to its physical size. However, such radars are also conspicuous, susceptible to clutter, and have low precision. Additionally, while faint or fleeting radar contacts make defenders aware that a stealth aircraft is present, reliably vectoring interception to attack the aircraft is much more challenging. According to the USAF an F-22 surprised an Iranian F-4 Phantom II that was attempting to intercept an American UAV, despite Iran's assertion of having military VHF radar coverage over the Persian Gulf.