What happened
While descending from cruise flight, the aircraft experienced a total loss of engine power. This failure necessitated a forced landing onto a shoreline composed of soft sand.
The investigation
A post-accident examination of the engine was conducted. Investigators found that connecting rods 2, 3, 4, 5, and 6 had separated from the crankshaft. Evidence of heat stress on the connecting rod bearings and a lack of lubrication were observed. Additionally, metal debris was found in the oil pan, and four holes were identified penetrating the bottom of the crankcase. During the engine teardown preparation, only approximately one quart of oil was drained from the oil sump.
Findings
The engine had accumulated 1,956 hours since its most recent major overhaul, which is near the recommended 2,000-hour interval between overhauls. The pilot reported that fuel and oil levels were normal for the flight and noted no anomalies prior to the power loss.