Primary finding
Probable cause
Fatigue failure of the engine crankshaft at the number 1 journal. A factor related to the accident was unsuitable terrain in the emergency landing area.
Investigator assessment
Analysis narrative
The pilot and two passengers were on a return flight, when there was a loss of engine power during cruise flight. According to the pilot, the engine began running rough after about one hour and ten minutes of flight. He radioed richmond approach control, and he was advised that he was 21 miles from his destination. He stated that he tried to reach chesterfield airport that was 10 miles away, but the engine seized with a loud clanking sound. A forced landing was made in a wheat field about 1/2 mile from chesterfield. During the forced landing, the right main gear separated. An examination of the engine revealed a broken crankshaft. The crankshaft was removed and sent to the NTSB lab in washington, dc. A metallurgical examination revealed the crankshaft had failed, where a fatigue crack had initiated on the surface of the aft radius of the #1 journal.
Source record
Factual narrative
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