Background
Before takeoff, the fuel tanks of the airplane were filled. No known witnesses observed the takeoff roll.
Witness Account
A witness located near the accident site reported that the airplane was flying at a low altitude and banked to the left. The witness believed the airplane would strike his house. The engine appeared to be operating at a low power setting and was noted to be running rough. The witness heard a sound he associated with a "bush hog," immediately followed by the sound of impact, after which he called 911.
Accident Site Examination
The airplane came to rest inverted on the ground. There was no swath through trees that would indicate a gradual descent. All components necessary to sustain flight were found in the immediate vicinity of the crash site, and there was no evidence of post-crash fire.
Flight Control and Propeller Examination
Examination of the flight controls revealed no evidence of preimpact failure or malfunction. At the accident site, a felled tree approximately 10 inches in diameter exhibited two propeller strikes. One cut was approximately 1.25 inches deep, and the other was approximately 4 inches deep. One cut showed evidence of black paint transfer. The propeller, which had its blades painted black on the aft side, was examined. One blade was bent slightly forward. The second blade exhibited leading edge twisting toward low pitch, was bent aft approximately 30 degrees, had its tip bent forward, and showed slight chordwise scratches extending from the tip inboard approximately 21 inches.
Engine and Systems Examination
Examination of the engine revealed no evidence of preimpact failure or malfunction. Bench testing of the fuel system components also showed no evidence of preimpact failure.
Performance Considerations
The runway used by the pilot had an upslope of approximately 1.5 percent. Performance calculations based on a weather observation at a nearby airport indicated that the distance to clear a 50-foot obstacle was 2,616 feet. The performance chart used was for a paved level runway, and no note described what distance to add for an upsloping runway.