Accident Summary
Shortly after takeoff, after climbing to 900 feet, the aircraft leveled off and the pilot reduced power to 24 inches of manifold pressure. Soon after, the pilot reported that the engine began to run rough and then quit. The pilot confirmed the fuel selector was positioned to the right fuel tank and that the auxiliary fuel boost pump was on. He checked each magneto with no improvement. The pilot subsequently landed the aircraft in a field with the landing gear retracted.
Investigation Details
Following the event, the engine was removed from the aircraft and placed on a test stand for an operational run. The engine started successfully. However, during a magneto check at 1,700 rpm, the engine briefly backfired when the right magneto position was selected, but it continued to run. The magneto assembly was removed and examined, but no determination could be made as to the reason for the reported total loss of engine power.
The fuel servo was also removed and tested on a stand. The test revealed that the fuel servo was not functioning normally, but it could not be determined whether this condition existed before the forced landing or resulted from the impact. Additionally, an airworthiness directive (AD) had not been accomplished on the aircraft.
Despite these examinations, the investigation was unable to determine the cause of the total loss of engine power.