Accident Description
A pilot was providing airplane rides to neighbors from his private airstrip. After taking off with a new passenger, a witness observed the aircraft skimming close to the ground after liftoff, followed by a quick climb. The aircraft then banked sharply to the right. During the bank, the nose dropped, and the aircraft descended rapidly until it impacted the ground.
Investigation Findings
The investigation revealed that the aircraft was equipped with a higher horsepower engine than authorized for that model. This larger engine required specific modifications to ensure adequate fuel flow and head pressure. These modifications included the addition of an engine-operated fuel pump and a wobble pump, or the installation of overhead fuel tanks. The investigation determined that these modifications had not been made.
Further examination showed that the inside of the fuel tank located behind the seats and the inside of the fuel lines were rusty. The rust was found to be restricting fuel flow.
Conclusion
The investigation identified two key factors: the installation of an unauthorized higher horsepower engine without the required modifications, and rust inside the fuel tank and fuel lines that restricted fuel flow. The source does not state a probable cause.