This October 2010 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Aircraft: Cessna 172. Injuries: None. Location: Portland, Ore. Aircraft damage: Substantial.
What reportedly happened: Prior to flight, the pilot looked inside the fuel tanks and noted that they appeared to be full, however, he did not recall how far down the fuel was from the fuel cap.
He departed and flew northwest 19 minutes to an airport to conduct a stop and go landing and takeoff. After departing that airport, he proceeded south for 2 hours 17 minutes to a second airport to do a full-stop landing.
When he departed the second airport toward his final destination, he estimated he had about 13 gallons of fuel remaining for the 48-minute flight. When the airplane was approximately seven miles south of the final destination, the engine lost power.
He attempted to restart the engine and was successful for a short time before the engine lost power again. He executed a forced landing into a nearby school yard.
The total distance for the flight was about 391 miles, with an estimated 3 hour 24-minute run time for the engine, without factoring in the wind, delays, and time spent on the ground.
Post-accident examination of the airframe and engine revealed no fuel in the right wing tank, approximately 1 gallon in the left wing tank, and about 1 ounce of fuel in the fuel line leading to the engine. There were no breaches in the fuel system. The Pilot Operating Handbook for the airplane stated that the airplane’s unusable fuel level was 1.5 gallons. Additionally, given the performance parameters of the flight, the engine would have burned approximately 7.5 gallons per hour and had a maximum range of 485 miles and 4.1 hours.
Probable cause: The pilot’s inadequate preflight inspection and failure to ensure adequate fuel was onboard for the flight, which resulted in a total loss of engine power due to fuel exhaustion.
For more information: NTSB.gov. NTSB Identification: WPR11LA01