Cessna P210N N4753K accident near Peach Springs, Arizona

Probable cause

A loss of engine power due to induced catastrophic internal failure of the engine as a result of the displacement and rotation of the number 2 main bearing that resulted in a fatigue fracture of the crankshaft.

NTSB analysis

During an instrument flight rules cross-country flight at 16,000 feet msl, the pilot reported to air traffic control that he had a total loss of engine power and was attempting to land at an airport about 12 miles from his current position. The pilot was unable reach the airport, and while trying to land on the desert floor, one of the main landing gear wheels hit a cactus and the airplane nosed over. During the recovery of the airplane, internal components of the engine where found in the debris field. The time recorded on the engine at the last annual inspection was 978 hours since major overhaul. A review of the airplane logbooks revealed that a top overhaul was completed on March 21, 2007, which included all 6 cylinders being removed, overhauled, and replaced. The engine failure occurred 120 hours since completion of the top overhaul. During the engine examinations, thermal discoloration of the crankshaft main journals and damage to various other internal components were noted. The crankshaft was fractured just forward of the number 2 main bearing. The number 2 main bearing was not located; however, the bearing support exhibited evidence of bearing shift, tang slot elongation, and rotation. The crankshaft main bearings and the connecting rod bearings were also damaged as a result of oil starvation, due to the number 2 main bearing rotation. The crankcase itself had been compromised just above the numbers 3 and 4 cylinders. The crankshaft was metallurgically examined at a laboratory. The crankshaft chemistry, case depth, surface hardness, and core hardness met specifications. The fracture initiated at the surface adjacent to the number 2 main bearing and progressed toward the number 3 rod journal in fatigue.

Text from the NTSB. Open the NTSB docket for LAX08LA153 for the full record.