What happened
As the airplane lifted off the runway and commenced its initial takeoff climb, the right engine experienced an uncontained failure. Following the event, the crew returned the aircraft to the departure airport to perform a single-engine landing. Upon arrival, emergency responders arrived on the scene and extinguished a fire that was confined to the hot section of the right engine.
The investigation
The investigation focused on the mechanics of the uncontained failure, which was traced to a fatigue crack located in the outer case of the combustion chamber at the forward drain boss weld. An analysis of fatigue striation measurements determined that a detectable crack was already present at the forward drain boss weld during an on-wing ultrasonic inspection conducted by company maintenance personnel in December 1995.