Rarely does a single aircraft change our daily lives as much as NASA 802 has. This aircraft, a modified F-8C Crusader, may look like a standard model from the outside. But inside, it is heavily modified. In the late 1960s, NASA Dryden Flight Research Center (now Armstrong) set out to create a safer, lighter and easier to maintain jet airplane by removing heavy, battle-damage prone mechanical flight control linkages, replacing them with digital flight control system with better redundancy. In this system, control inputs are routed to a computer. Then, the computer tells the control surfaces to move based on the pilot’s controls. Almost every jet aircraft and transport aircraft manufactured today uses this technology. If you’ve flown aboard an airliner, chances are, your life depended upon the research that this F-8 performed. This system changed the face of not only aviation, but our everyday lives. Unless you’re into vintage automobiles, the car that you own uses this technology to transmit your accelerator inputs to the engine. Some new cars use a complete drive-by-wire system with no mechanical linkages for steering.
We’ve established that this F-8 used a computer for control. But it didn’t use just any computer. At the time, the only machine up to the task of performing real time computations with 100% reliability was the Apollo Guidance Computer which was installed in the gun bay of the aircraft. But this wasn’t just any Apollo Guidance Computer. This F-8 flew with a computer than had just returned from the moon. Apollo 15 hardware was used in this aircraft. The final photo in the set shows the actual Apollo Guidance Computer Display and Keyboard (DSKY) that flew on Apollo 15 and was later installed in this F-8 aircraft. Initially, this F-8 flew with unflown backup computer hardware, but after this component malfunctioned, Dryden lobbied to NASA headquarters for a replacement. It took some convincing, but they were eventually allocated the computer that flew on Apollo 15.
NASA Dryden test pilot Gary E. Krier first flew this F-8 on May 25, 1972. Many were skeptical, but the aircraft performed flawlessly. Later, the Apollo hardware would be replaced with an improved, purpose-build computer. NASA 802 also went on to explore pilot induced oscillation suppression. This test program lasted for 13 years, completing its final flight on April 2, 1985. Digital fly-by-wire technology went on to fly with the Space Shuttle. The first operational fighter jet to use this technology was the F-16. Refinement of this system paved the way for later developments like Intelligent Flight Control, Auto Collision Avoidance, and Self-Repairing Flight Control systems, all thanks to NASA 802 and the people behind the Digital Fly-By-Wire research program.