Event Summary
As the airplane lifted off the runway and began its initial takeoff climb, the right engine experienced an uncontained failure. The flight crew returned the aircraft to the departure airport and executed a single-engine landing. Emergency response teams extinguished a fire that was confined to the hot section of the right engine.
Failure Analysis
Subsequent investigation determined that the uncontained failure resulted from a fatigue crack. The crack was located in the combustion chamber outer case at the forward drain boss weld. This crack compromised the structural integrity of the engine case, leading to the uncontained release of debris.
Inspection History
Analysis of fatigue striation measurements from the fracture surfaces indicated that a detectable crack existed at the forward drain boss weld when an on-wing ultrasonic inspection of the boss was performed by company maintenance personnel in December 1995. This inspection took place prior to the failure event.