JOINT BASE SAN ANTONIO-RANDOLPH, Texas — A failure of the third-stage rotor of the engine fan module caused a June 23, 2014, engine fire in an F-35A Lightning II, according to an Air Education and Training Command Accident Investigation Board report released June 5.  

The F-35A, which was assigned to the 58th Fighter Squadron, 33rd Fighter Wing, Eglin Air Force Base, Florida, was damaged during the takeoff portion of a training mission. The pilot safely aborted the takeoff and exited the aircraft. Following the aborted takeoff, emergency crews responded to the burning aircraft and extinguished the fire. There was no damage to private property and minor airfield damage. 

The Accident Investigation Board found the cause of the mishap was catastrophic engine failure. The engine failed when the third stage forward integral arm of a rotor fractured and liberated during the takeoff roll.

Pieces of the failed rotor arm cut through the engine’s fan case, the engine bay, an internal fuel tank, and hydraulic and fuel lines before exiting through the aircraft’s upper fuselage. Damage from the engine failure caused leaking fuel and hydraulic fluid to ignite and burn the rear two thirds of the aircraft. The total mishap damage is estimated to be in excess $50 million.

This Accident Investigation Board report only pertains to the immediate causes of this mishap and uses technical information available during the investigation by the assembled board at Eglin Air Force Base in August 2014. The board findings did not consider any ongoing analysis and testing of F-35 engines by aircraft engineers that may have occurred following this mishap.

For more information, please contact Air Education and Training Command Public Affairs at 210-652-4400.