ERA20LA271 · American Aviation AA 5 Undesignat

The pilot, who was not a certified airframe and powerplant mechanic, had recently reassembled the airplane, which had been in storage for 14 years. He told people that he was having problems with the fuel system and had an engine failure on a previous test flight. On the day of the accident, the pilot told his girlfriend that he was going to fly around the airport’s traffic pattern a few times but never returned. The airplane was located the following day about 1 mile west of the airport in heavily wooded terrain. Postaccident examination of the engine revealed the engine-driven fuel pump was heavily corroded, and water was found in the carburetor. Debris was found in the fuel line that connected the auxiliary fuel pump and the engine driven fuel pump. Rubber debris was also noted in the hose, consistent with damage to the rubber hose lining during fitting installation. The auxiliary fuel pump switch was found in the ON position at the accident site, which was consistent with normal takeoff and landing operations. The pilot had purchased 23 gallons of fuel about 1 month and a half before the accident and, according to the tachometer, had flown only 1.55 hours since the last annual inspection. The fuel burn rate for the engine was about 5.2 gallons per hour, thus giving the pilot about 14 gallons or more than 2 hours of fuel on board at the time he departed. A review of maintenance records revealed that the airplane had not had an annual inspection—as required by Federal Aviation Administration regulations—in almost 19 years prior to the accident. The engine had not had an annual inspection for almost 23 years or been overhauled in 23 years prior to the accident. Though the pilot was mechanically inclined, he had no experience maintaining aircraft and was not certified to do so. As a result, critical components that provided fuel to the engine were not properly installed or inspected. This lack of maintenance resulted in operating with water in the carburetor, corrosion on the engine driven fuel pump, and debris in the fuel system which impeded proper fuel flow to the engine and resulted in a loss of engine power while operating at a low altitude in the traffic pattern.

Verbatim NTSB analysis and probable cause from the NTSB dataset