Accident Sequence
The airplane collided with treetops located approximately 280 feet from the impact site on the side of a highway berm. The descent angle was measured at eight degrees. The left wing struck two small trees positioned 17 feet ahead of the initial ground scar. Following the impact, the airplane spun around and came to rest 9 feet from the end of the initial ground scar.
Examination of Propeller and Ground Evidence
No propeller ground scars were found. One propeller blade was undamaged, while the other blade exhibited only 4 inches of chordwise scratching on its backside.
Aircraft Systems Examination
Post-accident examination revealed flight control and engine continuity. The fuel system had been converted to a fuel injection system, and the airplane was fueled with autogas. A green hose was found connecting the fuel line at the firewall to the engine-driven fuel pump. The hose was marked "GATES 6C5D FLEXLINE 5/16 INCH 1500 PSI MAX HYD WP MADE IN USA." The manufacturer of the green hose reported it was a common hose for petroleum products such as transmission fluid or antifreeze and stated it had not manufactured aviation hoses for many years. Inspection of the green hose revealed that the B nut attached to the firewall was loose.
Maintenance Information
A witness reported that the pilot performed maintenance on the airplane, although the pilot was not an Airframe and Powerplant mechanic.