What happened
While operating in the airport traffic pattern, a Cessna 180 experienced a loss of engine power. Due to the loss of power, the aircraft landed short of the runway and collided with a wall.
The investigation
Investigators examined the aircraft's fuel system following the impact. There was no evidence that the fuel system had been compromised during the collision sequence, and no fuel leaks were detected.
Upon inspection of the tanks, approximately 4 gallons of 80/87 octane aviation gasoline were drained from the left wing tank. Both the fuselage tank and the right wing tank were found to be empty. No fuel was present in the line running from the fuel selector to the carburetor, though a trace amount of fuel was discovered within the engine primer system.
According to the Pilot Operating Handbook for the Cessna 180, the capacity of the wing bladder tanks is 32.5 gallons, with 27.5 gallons being usable. The handbook also notes that an additional 3.5 gallons of the 5 gallons classified as unusable can be utilized for level flight only. The fuel tanks are designed with outlet ports located in the rear inboard corner only.