Accident Summary
During a flight, the pilot experienced a loss of engine power. Initially, the engine operated normally, but after several minutes, it began running rough and oil appeared on the front windshield. Shortly thereafter, all engine power was lost. The pilot executed a forced landing in an open field approximately three-quarters of a mile from an airport, during which the airplane collided with a berm.
Engine Examination
Post-accident examination of the engine revealed approximately 10 quarts of oil in the sump and a hole in the engine case adjacent to the oil dipstick port. A subsequent teardown inspection determined that the connecting rod bearing on rod number 5 had overheated to failure, leading to a break in the connecting rod. The exact reason for the overheating was not determined.
Maintenance History
At the time of the accident, the engine had accumulated 40 hours since its last inspection and 806 hours since its last major overhaul. The total airframe time was approximately 6,325 hours.