What happened
The pilot, who is also a certified A&P mechanic, reported that the aircraft had been flown for one hour since its last inspection with all systems operating normally. On the day of the incident, his wife, also a pilot, departed their private airfield in Mercer, Pennsylvania, on a local flight but landed at Greenville 15 minutes later due to a rough-running engine.
Upon arrival at Greenville, the pilot replaced several fuel injection nozzles because of previous issues with the nozzles sticking due to varnish deposits. He then took off on a local test flight. At approximately 100 feet above ground level, the engine began to run rough and lose power. He made a left turn to return to the airfield. During the turn, the left wing struck the ground and the aircraft crashed.
The investigation
Subsequent investigation revealed that the internal mechanisms of the injector nozzles from cylinders 2, 3, and 4 were stuck in the closed position and were unable to produce any spray of fuel. This mechanical failure directly contributed to the loss of engine power during the critical phase of flight.
Findings
The primary finding was the failure of multiple fuel injection nozzles to deliver fuel due to internal mechanisms being stuck closed. This occurred despite recent maintenance aimed at resolving similar issues with varnish deposits. The pilot's attempt to return to the airfield resulted in a controlled flight into terrain as power could not be restored.