Primary finding
Probable cause
Fatigue failure of the engine crankshaft that originated from a heat check crack in the journal, adjacent to the #2 main journal forward fillet.
Investigator assessment
Analysis narrative
During flight at about 2000 feet over water, a partial loss of engine power occurred, followed by a total loss of power. The pilot attempted an engine restart with negative results and ditched at the mouth of a bay in ocean waters. He was fatally injured, but the passenger sustained only minor injuries. The aircraft was recovered, and an examination of the engine revealed the crankshaft had failed from fatigue cracking. Fatigue had initiated at a heat check crack in the journal at a position about 0.2 inch aft of the #2 main journal forward fillet & propagated through the adjacent #4 cheek. There was evidence of galling of the #2 main journal by contact with the associated bearing, which resulted in heat checks.
Source record
Factual narrative
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