F-22 Aircraft Database

Airframe was overstressed during tests with two external tanks. G-load limiter was exceeded when control was lost after the aircraft passed through the wake of an F-16. Maximum was to be 7.3 Gs but actually climbed to 11.7 Gs. Flight control software was found to be the problem. The aircraft landed safely but never flew again.

Crashed on take-off from Nellis AFB, Nevada at 15.40 hours. At the moment the wheels left the ground the aircraft began a series of un-commanded roll and pitch maneuvers that quickly became more violent. The pilot ejected moments before impact and the aircraft wreckage remained within Nellis AFB grounds.

Cause of the loss came about through a unique set of circumstances. The Flight Control System was inoperative at the time of the crash. A pilot must run the Initiate Built in Test (IBIT) on engine start in order to insure a fully functioning Flight Control System. The pilot shut down the engine for quick maintenance work and thought Auxiliary Power Unit (APU), which was running, would provide power for the Flight Control System. Believing the APU provided power to the Flight Control System, the pilot thought another IBIT after engine restart was unnecessary and taxied for his sortie. However the APU didn't provide continuous power and another IBIT should have been performed. Running the IBIT would not have corrected the issue but would have warned that the Flight Control System had a serious failure. As the engine shut down there was a power interruption that caused a catastrophic failure of the Flight Control System.