The lost of a USAF F-16 on May 16, 2019 has been attributed to the incorrect installation of two Integrated Servo Actuator check valves that lead to total hydraulic failure on the jet.
The valves were installed on Mar. 28 and the aircraft, no identified as assigned to the 114th Fighter Wing, flew 10 missions before the crash.
The pilot first notice a loss of pressure on tank A and was returning to March Air Reserve Base when tank B also failed. He ejected when the aircraft was about 250 feet above the ground and in a 40 degree bank.
Investigators found that that both screw caps were not properly screwed into the valve bodies. The retainers were found to be deformed.
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