Cessna 172 N738GN accident near Portland, Oregon

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.

NTSB analysis

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. The pilot departed from the airport 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, the pilot estimated he had about 13 gallons of fuel remaining for the 48-minute flight. About 7 miles south of his final destination, the engine lost power. The pilot attempted to restart the engine and was successful for a short time before the engine lost power again. The pilot 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. Postaccident 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 accident flight, the airplane's engine would have burned approximately 7.5 gallons per hour and had a maximum range of 485 miles and 4.1 hours.

Text from the NTSB. Open the NTSB docket for WPR11LA012 for the full record.