Forgotten Intake Plug Downed RAF F-35B

An RAF F-35B crashed last November because one of the engine intake plugs was left in. The U.K.’s Defence Safety Authority publicly released an interim report that was sent up the chain of command last June mainly to assure the brass that the plane itself wasn’t likely to blame for the mishap. “Based on the evidence obtained, the Panel is confident that the primary causal factor of the event was the left-hand intake blank remaining in the aircraft prior to launch reducing the engine power,” the report said. “This was most likely due to a combination of human, organizational and procedural factors.”

The aircraft was set up to launch in short takeoff mode from the deck of the HMS Queen Elizabeth II carrier on Nov. 21. The ship had just transited the Suez Canal and was operating in the eastern Mediterranean. All the run-up checks were normal but when the pilot hit 97 percent power for takeoff, the engine lagged and showed only 74 percent power. The pilot firewalled the throttle but still didn’t get takeoff power. He tried to abort but didn’t have enough deck left and he ejected. He landed safely back on the deck. The plane went off the ski jump ramp and, as it sank, the intake plug floated free. Crews grabbed the plug, but the plane went to the bottom and was recovered later.