What happened
Following the refueling of an empty right fuel tank, the pilot initiated a takeoff roll. Approximately 400 feet down the runway, the engine stopped running, forcing the pilot to abort the takeoff. To diagnose the issue, the pilot performed several engine run-ups and high-speed taxi tests; however, no malfunctions were detected during these procedures.
The pilot then attempted a second takeoff. While climbing through 75 feet AGL, the engine lost power once again. In an effort to avoid trees, houses, and electrical wires, the pilot executed a hard left turn. The aircraft subsequently impacted down-sloping terrain. There were no injuries reported.
The investigation
Investigators examined fuel samples, which were found to be clear and free of any contaminants. The investigation also considered the condition of the airframe. The pilot noted that mud wasp nests are frequently found throughout the aircraft's structure. Because the right fuel tank had remained empty for three to four weeks prior to the incident, it was determined that a mud wasp nest may have blocked the fuel vent. This blockage would create a vacuum effect within the unoccupied space of the tank, preventing fuel from flowing into the fuel lines and leading to engine starvation.