What happened
The pilot reported conducting a comprehensive preflight inspection of the aircraft, which included draining the sumps and the fuel strainer. At that time, no water was detected in the fuel system. Following takeoff, while the aircraft was operating on the downwind leg of the traffic pattern, the engine ceased functioning. The pilot attempted to return to the airport for an emergency landing; however, the aircraft collided with a powerline, a tree, and a vehicle before coming to rest on a roadway.
The investigation
A post-crash examination of the fuel system revealed that approximately 10 ounces of water had accumulated in the fuel strainer. According to the pilot, the aircraft had been tied down outside and left uncovered for at least a month prior to the accident. Local residents confirmed that a substantial amount of rain had fallen in the area during that same month. No other preimpact malfunctions or failures were found.
Findings
The presence of water contamination in the fuel system was identified as the primary factor leading to the engine failure. The aircraft was left exposed to the elements for an extended period, allowing moisture to enter the fuel system despite the initial preflight checks. The pilot's decision to drain the sumps and fuel strainer prior to flight did not prevent the accumulation of water during the storage period. The collision with ground objects resulted in minor injuries to four individuals in a vehicle and no injuries to one other individual.
Safety message
This incident highlights the importance of protecting aircraft from environmental exposure, particularly rain, when parked for extended periods. Pilots should ensure that aircraft are properly covered or stored in hangars to prevent water ingress into the fuel system, even if preflight checks show no immediate issues.