American Aviation AA 1 N6107L accident near Newnan, Georgia

Probable cause

The flight instructor’s inadequate preflight fuel planning, which resulted in an interruption of the fuel supply to the engine and a subsequent a total loss of engine power due.

NTSB analysis

During the preflight inspection of the airplane, the flight instructor used the sight gauges inside the airplane to estimate that there was a total of approximately 10 to 11 gallons of fuel on board between the two wing fuel tanks. The flight instructor and the pilot receiving instruction departed and conducted maneuvers, simulated losses of engine power, and performed at least eight takeoffs and landings over the course of about 50 minutes. During a simulated loss of engine power in the airport traffic pattern, after descending to 300 ft above the ground, the pilot receiving instruction attempted to perform a go-around. The engine did not respond as expected and they performed a forced landing to a grassy area bordering the runway. During the landing attempt, the airplane impacted a taxiway marker and trees bordering the airport, resulting in substantial damage to the left wing and fuselage. The amount of fuel onboard at the time of the accident and its distribution was not determined; however, a postaccident test run of the engine revealed no evidence of any preimpact mechanical failures or malfunctions that would have precluded normal operation.

During a postaccident interview, the flight instructor estimated that the airplane’s fuel consumption was about 6 gallons per hour (gph). Review of fuel consumption data from the engine and airframe manufacturer showed that the engine could be expected to consume between 6.5 and 7.3 gallons per hour at higher power settings, and that the fuel consumption could be as much as 9.5 gallons per hour when producing full power. These fuel consumption rates did not account for fuel consumed during taxi, run up, and takeoff.

Given the quantity of fuel onboard at the time of departure, the duration of the flight, the likely fuel consumption rate of the engine, and that the engine was successfully test run after the accident, it is likely that the loss of engine power was the result of an interruption of fuel flow to the engine; however, whether the fuel supply was completely exhausted or only the fuel in one of the tanks was exhausted could not be determined based on the available information. Had the flight instructor elected to depart with additional fuel, it is likely that the accident would not have occurred.

Text from the NTSB. Open the NTSB docket for ERA20LA308 for the full record.