Now, all F-35s have been stood down.
An integrated power package or IPP failure Tuesday at Edwards Air Force Base, Calif., has grounded all 20 F-35 Joint Strike Fighters. The decision comes while the fleet of F-22 jets – the nation’s newest air superiority fighter – remains grounded due to on-board oxygen generation system issues.
Reports indicated that technicians were conducting a standard ground maintenance engine run on the F-35, still in the early stages of production, when the IPP failed. The IPP provides power to start the engine and helps cool the aircraft. It combines the functions of the auxiliary power unit, emergency power system and environmental controls.
The suspension affects all F-35 test aircraft and initial production systems. There were no injuries to the pilot or ground crew. Officials said determining the cause of the incident has the highest priority.
The same aircraft experienced an in-flight dual generator problem five months ago that led to a temporary suspension of F-35 operations