Accident Overview
Shortly after takeoff at night, the pilot of a single-engine airplane experienced a loss of engine power while operating over a residential area. The airplane subsequently struck a telephone pole and crashed onto a street, where it was consumed by fire.
Engine Maintenance History
Records indicated that the engine had experienced a propeller strike at 1,828 hours of operation. It was overhauled at 2,164 hours and again at 3,407 hours. The accident occurred at 3,486 hours. No maintenance records were available for the first overhaul. During the second overhaul, the crankshaft was found to be undersized by 0.003 inches.
Crankshaft Failure
Examination revealed that the crankshaft had failed at the rear of the number 3 crankpin. Metallurgical analysis determined that the fracture originated subsurface in an area of stress concentration. Cracks containing nitriding residue were identified; these cracks had not been detected by nondestructive testing during the overhaul process.
Regulatory Context
The Federal Aviation Administration does not require certification of nondestructive testing operators, according to available information.