McDonnell Douglas YRF-4C Phantom II--Fly By Wire Demonstrator
Advances in microprocessor technology opened up huge new vistas in aviation. While aviation engineers had been experimenting with aerodynamically unstable aircraft for years, such designs were inherently dangerous to fly: though they offered advanced performance beyond that of more conventional aircraft, human beings simply could not make the hundreds per second adjustments required to fly them effectively, even when assisted by hydraulically powered control surfaces. Microprocessors, however, could. By scattering these miniature computers throughout the aircraft and linking them to a single computer, an aircraft could be made unstable and yet controllable by the pilot. Since the microprocessors would be linked by wires and control signals rather than hydraulic lines, this system became known as “fly-by-wire.”
The US Air Force began experiments with fly-by-wire (FBW) aircraft in the 1960s, and by 1972, were ready to try it on a full-scale design. Chosen for the project was the first RF-4C Phantom II prototype, YRF-4C 62-12200. This aircraft had not only served as the first RF-4C, it had also been modified into the first gun-armed F-4E, earning it the moniker “Father of All Phantoms.” Having already been converted back to RF-4C standard, the camera ports were fared over and a FBW system was installed, with the hydraulic system remaining intact as a backup. Designated the Precision Aircraft Control Technology (PACT) demonstrator, 62-12200 first flew under FBW control on 22 July 1973. Testing went without a hitch for over a year.
To further experiment with non-conventional technology, the USAF decided to save money and convert 62-12200 into a Control Configured Vehicle (CCV) demonstrator as well. This involved adding movable canards to the intakes and lead ballast to the rear fuselage to deliberately destabilize the YRF-4C. The task was to prove that FBW technology could effectively control an unstable design. Again, testing went smoothly throughout 1974. When the program was complete, 62-12200 was retired from service. As it was a unique version of the Phantom II, and had served as the prototype for two of the most important of F-4 variants, the aircraft would be saved from storage and scrapping, and was flown to the National Museum of the USAF at Wright-Patterson AFB, Ohio, in 1978, where it remains on display.
Dad and Bary Poletto did an extensive conversion of a 1/72 F-4E to produce the FBW demonstrator. It is painted overall gloss white with light blue Systems Command stripes along the fuselage; the underside is dark blue. It is on display at the Malmstrom AFB Museum.
McDonnell Douglas YRF-4C Phantom II--Fly By Wire Demonstrator
Advances in microprocessor technology opened up huge new vistas in aviation. While aviation engineers had been experimenting with aerodynamically unstable aircraft for years, such designs were inherently dangerous to fly: though they offered advanced performance beyond that of more conventional aircraft, human beings simply could not make the hundreds per second adjustments required to fly them effectively, even when assisted by hydraulically powered control surfaces. Microprocessors, however, could. By scattering these miniature computers throughout the aircraft and linking them to a single computer, an aircraft could be made unstable and yet controllable by the pilot. Since the microprocessors would be linked by wires and control signals rather than hydraulic lines, this system became known as “fly-by-wire.”
The US Air Force began experiments with fly-by-wire (FBW) aircraft in the 1960s, and by 1972, were ready to try it on a full-scale design. Chosen for the project was the first RF-4C Phantom II prototype, YRF-4C 62-12200. This aircraft had not only served as the first RF-4C, it had also been modified into the first gun-armed F-4E, earning it the moniker “Father of All Phantoms.” Having already been converted back to RF-4C standard, the camera ports were fared over and a FBW system was installed, with the hydraulic system remaining intact as a backup. Designated the Precision Aircraft Control Technology (PACT) demonstrator, 62-12200 first flew under FBW control on 22 July 1973. Testing went without a hitch for over a year.
To further experiment with non-conventional technology, the USAF decided to save money and convert 62-12200 into a Control Configured Vehicle (CCV) demonstrator as well. This involved adding movable canards to the intakes and lead ballast to the rear fuselage to deliberately destabilize the YRF-4C. The task was to prove that FBW technology could effectively control an unstable design. Again, testing went smoothly throughout 1974. When the program was complete, 62-12200 was retired from service. As it was a unique version of the Phantom II, and had served as the prototype for two of the most important of F-4 variants, the aircraft would be saved from storage and scrapping, and was flown to the National Museum of the USAF at Wright-Patterson AFB, Ohio, in 1978, where it remains on display.
Dad and Bary Poletto did an extensive conversion of a 1/72 F-4E to produce the FBW demonstrator. It is painted overall gloss white with light blue Systems Command stripes along the fuselage; the underside is dark blue. It is on display at the Malmstrom AFB Museum.