Air Safety Institute Safety Spotlight
Important fuel lessons
On January 10, 2001, a flight instructor learned a valuable lesson about who is pilot in command during instructional flights when the Grumman American AA-1B he and a student were flying was destroyed on impact following fuel exhaustion. The student pilot and the flight instructor both suffered serious injuries. Visual meteorological conditions prevailed at the time of the accident.
The student stated that during the preflight, he "&checked the fuel levels prior to flight that day by visually observing the sight tubes for each tank." The student and the instructor believed that they had two hours of fuel on board. The student's logbook showed four flights in the accident airplane, but no flights had been recorded for the eight months prior to the accident. The CFI had 903 hours of dual given and 0.9 hours in the Grumman AA-1B.
The pair had just finished some air work, including slow flight and power-off stalls, and was proceeding to a nearby airport for some practice landings. The first approach resulted in a go-around because of a helicopter on the runway. After the go-around, they decided to return to their home airport for more pattern work. The first touch and go was completed, during which the student applied full power, moved the carburetor heat to the "Off" position, and retracted the flaps. At approximately 200 feet agl, the engine stopped. The CFI took control of the aircraft, and the student began to troubleshoot the engine failure. The student switched the fuel tanks and turned on the fuel boost pump. He did not have time to activate the starter before impact.
In reconstructing the flights leading up to the accident, the NTSB determined approximately 7.4 Hobbs hours had been flown on 35.6 gallons of available fuel, a fuel burn of approximately 4.81 gallons per hour. The operating manual for the Lycoming O-235-C2C installed on the aircraft indicates fuel consumption of between 5.3 and 5.9 gallons per hour during operations at 2,500 feet above sea level. The outcome indicates that the student and CFI really had no idea of the fuel level at takeoff.
The NTSB determined the cause of this accident to be the flight instructor's failure to ensure the student had an adequate supply of fuel available, and the student's failure to refuel the aircraft, which resulted in fuel exhaustion.
Fuel exhaustion accidents occur at a rate of more than one per week. This accident provides two important lessons -- one for all pilots and one particularly for instructors. For all pilots, it is important to know how much fuel you have on board prior to liftoff and have a plan to land with your reserves unused. The AOPA Air Safety Foundation recommends planning to land with one hour of fuel on board for day VFR flights, double the FAA reserve requirement. For instructors, the accident serves as a stark reminder of who has the final responsibility on dual instructional flights.
Download ASF's Fuel Awareness Safety Advisor for more information.
Kristen Hummel manages the aviation safety database for the AOPA Air Safety Foundation. She holds a commercial pilot certificate with multiengine and instrument ratings.
By Kristen Hummel