Lockheed SR-71A Blackbird
The loss of Francis Gary Powers’ U-2A on 1 May 1960 underscored the fact that the U-2 was not as invulnerable to interception as originally hoped. If altitude was no longer a defense against Soviet air defenses, speed would be. Clarence “Kelly” Johnson, who had designed the U-2, was put to work with his legendary “Skunk Works” section of Lockheed to develop a very high-speed reconnaissance aircraft to supplement the U-2, named first the A-12—like the U-2’s use of the innocuous “utility” designation, the A-12 would use the outdated “attack” designation, though it carried no weapons. This designation was later changed as the design evolved, to the RS-71; this in turn was reversed to SR-71 by General Curtis LeMay, for strategic reconnaissance.
Work on the A-12/SR-71 was done in the strictest secrecy, although its existence was revealed in 1964 by President Lyndon Johnson. Virtually everything about the aircraft had to be invented on the spot, and even the tools used in its production had to be specially built first. The SR-71 was built of mostly light titanium, and design specifications were such that normal tools would damage the airframe. Emphasis was made on stealth and especially high speed: the SR-71’s intended normal operating speed was in excess of Mach 3, which at that time had only been achieved with the rocket-powered X-15. To reach this speed, the aircraft would use J58 ramjets: once at altitude, the SR-71 would be accelerated to the point that the airflow over its shock-cone intakes would be forced into the engines at above the speed of sound. At speed above Mach 3, the SR-71 was more or less pulling itself through the air by brute force, with the engines only providing thirty percent of the thrust.
At these speeds, heat was a real problem, as the fuselage would rapidly heat up. Titanium sheds heat better than most metals, and the SR-71 was designed with corrugated “skin” that would easily expand and contract with changing airspeed, heat, and altitude. Panels in the aircraft were deliberately designed to be loose on the ground and contract at altitude; fuel leaks on SR-71s were so commonplace that they were not remarked upon. Even the fuel and black paint scheme (actually a very dark blue) were placed and applied to diffuse heat away from leading edges.
The A-12, and the short-lived YF-12 interceptor, lacked the extended chines of the SR-71; these were used to enhance the aircraft’s stealth techniques to reflect away radar. While in practice this did not work—Soviet radars could easily track the SR-71 through its heat plume—it actually made the aircraft more controllable and gave it increased lift. The SR-71 was not an easy aircraft to fly, but it was considerably easier than the U-2, and was generally reliable unless it lost an engine: the high speeds of the aircraft occasionally caused engine disintegration, which would usually destroy the SR-71. It was also very unstable in bad weather, should it run into any after takeoff or on approach. Because of its high speed, the approach “pattern” for SR-71s to land at their home base of Beale AFB, California, had to begin at St. Louis, Missouri. The navigation system was adapted from that of the Skybolt air-launched nuclear missile, while cameras and side-looking radar was carried in the nose or the chines; these could be swapped out as the mission required. Extensive electronic countermeasures were also carried.
The SR-71 first flew in December 1964 and entered service in 1966—only six years after being ordered, an impressive achievement given its highly advanced nature. It was immediately committed to service over Vietnam under Operation Giant Scale, where its operations were meant to be “secret,” though everyone, including the North Vietnamese, were aware of its presence. Soviet attempts to intercept the SR-71 were not successful: MiG-25 Foxbat interceptors could reach Mach 3, but Foxbat pilot Viktor Belenko later related the “ridiculous ease” that SR-71s could leave behind even the speedy MiG-25. Even later variants of SAMs and increasingly more sophisticated Soviet aircraft still could not intercept the SR-71, which quickly acquired the nickname Blackbird for its paint scheme; its snakelike chines earned it the nickname (and later callsign) Habu from Okinawans around Kadena airbase, where SR-71s often operated from, after the habu pit viper.
One thing that the Blackbird could not outrace was the cost of operation: it required special JP-7 fuel, which in turn required specialized KC-135Q tankers to refuel them. The tooling for the aircraft had been destroyed on the order of Secretary of Defense Robert McNamara in 1967, which meant the 32 operational SR-71s had to be maintained by cannibalizing either the retired A-12 fleet or other Blackbirds to stay operational. It survived several attempts at forced retirement in the 1980s until the breakup of the Communist Bloc finally brought an end to SR-71 operations in 1989, though developments were underway to equip the Blackbird with synthetic-aperture radar and even more advanced engine designs that could propel it up to Mach 6.
This retirement proved to be short-lived: during the First Gulf War, the USAF keenly felt the loss of the SR-71, which could provide better coverage of Iraq than satellites and was not as vulnerable as other reconnaissance platforms. Over heavy opposition from the USAF (which wanted to channel increasingly lower budget money towards the B-2 Spirit and development of the RQ-4 Global Hawk), three SR-71s were returned to service in 1993. After annual fights between the USAF, Congress, and President Bill Clinton over keeping the Blackbird in service, it was finally retired for good in 1998, except for two aircraft to be handed over to NASA for flight testing. NASA’s two aircraft only lasted a few years longer, with the end finally coming in 1999.
Of the 32 SR-71s produced (including SR-71A operational aircraft, SR-71B conversion trainers, and the single SR-71C “hybrid” trainer, converted from an A-12), 12 were lost in accidents. The remaining 20 aircraft have all been preserved in museums around the world.
This is SR-71A 61-7973, which entered service in 1964, initially flying from Edwards AFB, California to test SR-71 systems; one of the pilots on its first flight was Darryl Greenamyer, who was to later become a famous air racer. It joined the 9th Strategic Reconnaissance Wing at Beale AFB, California in 1968, and took part in both Operation Glowing Heat sorties over North Vietnam (forward deployed to Kadena, Okinawa) and Senior Crown missions on the periphery of the USSR (forward deployed to RAF Mildenhall, UK). In July 1987, 61-7973 was flying in an airshow at Mildenhall when the crew accidentally overstressed the airframe. The decision was made to withdraw 61-7973 from service and it was flown back to Edwards. It was repaired and placed in storage, but when the SR-71 went through its first retirement in 1990, 61-7973 made one last flight: it captured the transcontinental flight record from New York to Edwards in 68 minutes. It was then retired to the Blackbird Airpark at the entrance to the Skunk Works' Plant 42 in Palmdale, California.
Because the Blackbird Airpark was closed by the time we got to Palmdale in May 2021, I had to shoot over the fence, which means this isn't the best picture of 61-7973. It is probably the first time I was able to get a full side-on shot of a SR-71, however, along with one of the J58 turbojets alongside. 61-7973 is painted as it would have been during Glowing Heat missions, with only the tail number in red and no USAF markings.
EDIT (June 2023): A slightly better shot of this aircraft, taken in 2023, without the fence in the way.
Lockheed SR-71A Blackbird
The loss of Francis Gary Powers’ U-2A on 1 May 1960 underscored the fact that the U-2 was not as invulnerable to interception as originally hoped. If altitude was no longer a defense against Soviet air defenses, speed would be. Clarence “Kelly” Johnson, who had designed the U-2, was put to work with his legendary “Skunk Works” section of Lockheed to develop a very high-speed reconnaissance aircraft to supplement the U-2, named first the A-12—like the U-2’s use of the innocuous “utility” designation, the A-12 would use the outdated “attack” designation, though it carried no weapons. This designation was later changed as the design evolved, to the RS-71; this in turn was reversed to SR-71 by General Curtis LeMay, for strategic reconnaissance.
Work on the A-12/SR-71 was done in the strictest secrecy, although its existence was revealed in 1964 by President Lyndon Johnson. Virtually everything about the aircraft had to be invented on the spot, and even the tools used in its production had to be specially built first. The SR-71 was built of mostly light titanium, and design specifications were such that normal tools would damage the airframe. Emphasis was made on stealth and especially high speed: the SR-71’s intended normal operating speed was in excess of Mach 3, which at that time had only been achieved with the rocket-powered X-15. To reach this speed, the aircraft would use J58 ramjets: once at altitude, the SR-71 would be accelerated to the point that the airflow over its shock-cone intakes would be forced into the engines at above the speed of sound. At speed above Mach 3, the SR-71 was more or less pulling itself through the air by brute force, with the engines only providing thirty percent of the thrust.
At these speeds, heat was a real problem, as the fuselage would rapidly heat up. Titanium sheds heat better than most metals, and the SR-71 was designed with corrugated “skin” that would easily expand and contract with changing airspeed, heat, and altitude. Panels in the aircraft were deliberately designed to be loose on the ground and contract at altitude; fuel leaks on SR-71s were so commonplace that they were not remarked upon. Even the fuel and black paint scheme (actually a very dark blue) were placed and applied to diffuse heat away from leading edges.
The A-12, and the short-lived YF-12 interceptor, lacked the extended chines of the SR-71; these were used to enhance the aircraft’s stealth techniques to reflect away radar. While in practice this did not work—Soviet radars could easily track the SR-71 through its heat plume—it actually made the aircraft more controllable and gave it increased lift. The SR-71 was not an easy aircraft to fly, but it was considerably easier than the U-2, and was generally reliable unless it lost an engine: the high speeds of the aircraft occasionally caused engine disintegration, which would usually destroy the SR-71. It was also very unstable in bad weather, should it run into any after takeoff or on approach. Because of its high speed, the approach “pattern” for SR-71s to land at their home base of Beale AFB, California, had to begin at St. Louis, Missouri. The navigation system was adapted from that of the Skybolt air-launched nuclear missile, while cameras and side-looking radar was carried in the nose or the chines; these could be swapped out as the mission required. Extensive electronic countermeasures were also carried.
The SR-71 first flew in December 1964 and entered service in 1966—only six years after being ordered, an impressive achievement given its highly advanced nature. It was immediately committed to service over Vietnam under Operation Giant Scale, where its operations were meant to be “secret,” though everyone, including the North Vietnamese, were aware of its presence. Soviet attempts to intercept the SR-71 were not successful: MiG-25 Foxbat interceptors could reach Mach 3, but Foxbat pilot Viktor Belenko later related the “ridiculous ease” that SR-71s could leave behind even the speedy MiG-25. Even later variants of SAMs and increasingly more sophisticated Soviet aircraft still could not intercept the SR-71, which quickly acquired the nickname Blackbird for its paint scheme; its snakelike chines earned it the nickname (and later callsign) Habu from Okinawans around Kadena airbase, where SR-71s often operated from, after the habu pit viper.
One thing that the Blackbird could not outrace was the cost of operation: it required special JP-7 fuel, which in turn required specialized KC-135Q tankers to refuel them. The tooling for the aircraft had been destroyed on the order of Secretary of Defense Robert McNamara in 1967, which meant the 32 operational SR-71s had to be maintained by cannibalizing either the retired A-12 fleet or other Blackbirds to stay operational. It survived several attempts at forced retirement in the 1980s until the breakup of the Communist Bloc finally brought an end to SR-71 operations in 1989, though developments were underway to equip the Blackbird with synthetic-aperture radar and even more advanced engine designs that could propel it up to Mach 6.
This retirement proved to be short-lived: during the First Gulf War, the USAF keenly felt the loss of the SR-71, which could provide better coverage of Iraq than satellites and was not as vulnerable as other reconnaissance platforms. Over heavy opposition from the USAF (which wanted to channel increasingly lower budget money towards the B-2 Spirit and development of the RQ-4 Global Hawk), three SR-71s were returned to service in 1993. After annual fights between the USAF, Congress, and President Bill Clinton over keeping the Blackbird in service, it was finally retired for good in 1998, except for two aircraft to be handed over to NASA for flight testing. NASA’s two aircraft only lasted a few years longer, with the end finally coming in 1999.
Of the 32 SR-71s produced (including SR-71A operational aircraft, SR-71B conversion trainers, and the single SR-71C “hybrid” trainer, converted from an A-12), 12 were lost in accidents. The remaining 20 aircraft have all been preserved in museums around the world.
This is SR-71A 61-7973, which entered service in 1964, initially flying from Edwards AFB, California to test SR-71 systems; one of the pilots on its first flight was Darryl Greenamyer, who was to later become a famous air racer. It joined the 9th Strategic Reconnaissance Wing at Beale AFB, California in 1968, and took part in both Operation Glowing Heat sorties over North Vietnam (forward deployed to Kadena, Okinawa) and Senior Crown missions on the periphery of the USSR (forward deployed to RAF Mildenhall, UK). In July 1987, 61-7973 was flying in an airshow at Mildenhall when the crew accidentally overstressed the airframe. The decision was made to withdraw 61-7973 from service and it was flown back to Edwards. It was repaired and placed in storage, but when the SR-71 went through its first retirement in 1990, 61-7973 made one last flight: it captured the transcontinental flight record from New York to Edwards in 68 minutes. It was then retired to the Blackbird Airpark at the entrance to the Skunk Works' Plant 42 in Palmdale, California.
Because the Blackbird Airpark was closed by the time we got to Palmdale in May 2021, I had to shoot over the fence, which means this isn't the best picture of 61-7973. It is probably the first time I was able to get a full side-on shot of a SR-71, however, along with one of the J58 turbojets alongside. 61-7973 is painted as it would have been during Glowing Heat missions, with only the tail number in red and no USAF markings.
EDIT (June 2023): A slightly better shot of this aircraft, taken in 2023, without the fence in the way.