NTSB Factual Report

On October 10, 2010, about 1855 Pacific daylight time, a Cessna 172N, N738GN, experienced a loss of engine power during cruise flight and made a forced landing in the playground at the Robert Grey Middle School, about 7 miles southwest of the Portland International Airport (PDX), Portland, Oregon. Snohomish Flying Services operated the flight under the provisions of 14 Code of Federal Regulations Part 91 as a personal cross-country flight. The commercial pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed for the flight, and an instrument flight rules (IFR) flight plan had been filed. The flight departed Harvey Field Airport (S43), Snohomish, Washington, at an unknown time. The flight was destined for PDX.

In a telephone conversation with a Federal Aviation Administration (FAA) inspector, the pilot reported that prior to the flight he checked the fuel quantity by looking inside of the fuel tanks. The pilot further stated that the tanks “appear[ed] full, but that the fuel was not spilling out like it sometimes does.” The pilot did not recall how far down the fuel was from the fuel cap.

The pilot reported that after departing from the airport he flew northwest 36 miles (about 19 minutes) to Skagit Regional Airport, Burlington, Washington, to conduct a stop and go. After departing, he climbed to 9,000 feet and proceeded south 263 miles (about 2 hours 17 minutes) to Mahlon Sweet Field Airport in Eugene, Oregon, where he landed and taxied back to the runway to prepare for his final leg to PDX. The pilot reported that upon departing Eugene, he estimated he had 13 gallons of fuel remaining for the 92-mile (about 48 minutes) flight to PDX. Approximately 7 miles southwest of PDX the engine lost power. The pilot attempted to restart the engine several times and was able to get it running for a short time, but then it lost power again. The pilot executed a forced landing into a nearby school yard.

Post accident examination of the engine and airframe by a FAA inspector revealed no fuel in the right wing tank, approximately 1 gallon of fuel 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 Cessna Skyhawk 172N Pilot Operating Handbook (POH) states that the airplane’s unusable fuel level is 1.5 gallons.

The total distance for the flight was about 391 miles. Without factoring in winds, delays, and time spent on the ground, the flight has a total estimated time of 3 hours 24 minutes. According to the Cessna Skyhaw 172N POH at about 9,000 feet, with a leaned mixture, the airplane burns about 7.5 gallons per hour. The POH also states that at an altitude of 8,000 feet, with standard fuel tanks, 75% power, and no wind, the airplane has a maximum range of 485 miles and 4.1 hours.

NTSB 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.