What happened
During the flight, the engine initially operated normally. After several minutes of operation, the engine began running roughly and oil appeared on the front windshield. Following this, all engine power was lost. The pilot attempted a forced landing in an open field located approximately 3/4-mile from the airport, but the Cessna (type not specified in source) collided with a berm during the maneuver.
The investigation
An examination of the engine revealed approximately 10 quarts of oil in the sump and a hole in the engine case located next to the oil dipstick port. A teardown examination determined that the connecting rod bearing on rod number 5 had overheated to failure, which subsequently caused the connecting rod to break. At the time of the accident, the engine had been operated for 40 hours since its last inspection and 806 hours since its last major overhaul. The aircraft had a total time of approximately 6,325 hours.
Findings
- The engine experienced a complete loss of power due to mechanical failure.
- A hole in the engine case allowed oil to escape, as evidenced by oil on the windshield.
- The failure was caused by the overheating and subsequent breakage of the number 5 connecting rod bearing.