Military and officials overseeing the F-35 joint strike fighter program said Wednesday that ground testing of the aircraft could resume, but not flight testing.
Flights of the 20 F-35s involved in testing and training were suspended Aug. 3 after a mechanical failure in the integrated power package, which starts the engine, generates power and provides air conditioning. The problem occurred in a jet being tested at Edwards Air Force Base in California.
An investigation found that a control valve problem caused the power system to fail, but the reason for the valve failure and a solution have not been determined.
Resuming ground tests "is a major step for the F-35 fleet returning to flight, [but] further reviews are required prior to lifting the suspension of flight operations" for the F-35, said Joe DellaVedova, spokesman for the joint program office.
DellaVedova said the impact of the flight suspension on the testing schedule and preparations for beginning military pilot training are still being evaluated but the test program had extra time built into its schedule in case of delays.
The F-35 is the largest, most complex and costliest Pentagon weapons development program and has run far behind schedule and over budget, leading to increased scrutiny from the Defense Department and Congress. In part because of the estimated $382 billion cost for 2,400-plus aircraft and the delays, the F-35 is frequently mentioned as a likely target for budget cuts.
Lockheed Martin Aeronautics in Fort Worth is the prime contractor on its development and production.
