Incident Overview
A pilot reported that the engine experienced power loss during flight, sputtering and quitting before ultimately failing. The pilot executed a forced landing in a bean field, during which the aircraft nosed over. The pilot, who is also an Airframe and Powerplant (A&P) mechanic, had been applying a sloshing/sealing compound, Randolph Tank Sealer #802, to the fuel tank prior to the flight.
Investigation Findings
Following the accident, investigators discovered the sealing compound both inside the fuel line and on the fuel strainer. Further examination revealed that the compound had been purchased in 1980 and was dated December 9, 1978. The failure of the compound to adhere properly to the fuel tank was attributed to its stale condition, resulting in the compound loosening and migrating into the fuel system.
Cause Determination
The investigation determined that the compromised adhesion of the fuel tank sealer, due to its age and staleness, led to contamination of the fuel system. This contamination caused the engine to lose power, ultimately necessitating the forced landing. No other contributing factors were identified.