American Aviation AA1 N9218L accident near Warthen, Georgia

Probable cause

A fuel leak from the carburetor float bowl due to a missing plug, which resulted in excessive fuel consumption and a total loss of engine power due to fuel exhaustion. Contributing to the accident was the pilot's decision to depart on the accident flight leg after noting the airplane's unexpectedly high fuel consumption during the previous leg.

NTSB analysis

The commercial pilot reported that, on the day of the accident, he filled each tank of the newly purchased airplane with 12.5 gallons of fuel. On his first flight, after about 20 minutes of flying, he noticed he was running out of fuel. The pilot thought the fuel burn was very high and decided to land at the nearest airport; he added about 24 gallons of fuel. After departure and about 30 minutes of flying, he again noticed that the airplane was running out of fuel. He planned to land at the nearest airport; however, about 15 miles away from the airport, the engine lost total power. The pilot switched fuel tanks and turned on the electric boost pump, and the engine restarted. A few minutes later, the engine lost total power again. The pilot noticed both fuel tanks were out of fuel. During a forced landing in a field, the airframe was substantially damaged.

Postaccident examination of the engine revealed that the carburetor float bowl plug was missing, which allowed fuel to leak out of the carburetor. Thus, the airplane's fuel consumption during the flight would have increased substantially and likely resulted in exhaustion of the airplane's available fuel supply at a greater-than-normal rate. Although the pilot reported that the airplane was recently inspected before he purchased it, no maintenance records were available for review, so the scope of work done to, or inspections of, the carburetor could not be determined. Further, the pilot's decision to depart on the accident flight leg after noting excessive fuel consumption on the previous leg contributed to the accident.

Text from the NTSB. Open the NTSB docket for ERA18TA250 for the full record.