What happened
The flight began with a trip from one airstrip to another. Following an initial landing and subsequent takeoff, the pilot returned to the departure airstrip to perform a simulated forced landing. After completing the simulation, the pilot back-taxied and departed toward the north.
While flying at 250 feet above ground level (AGL), the engine lost power. In an attempt to restore power, the pilot switched fuel selection from the right tank to the left tank and primed the engine. Although the engine surged briefly, it failed again. The pilot then executed a forced landing into a swampy area. There were no injuries reported.
The investigation
An investigation of the aircraft's fuel supply revealed that the left tank contained 6 gallons of aviation 100LL fuel, while the right tank contained 3.5 gallons of automotive fuel. The aircraft was equipped with two wing tanks, each having a capacity of 12.5 gallons. The operations manual for the aircraft specified that takeoff should not be performed with less than one-quarter of a tank of fuel remaining.
An engine test run conducted on the aircraft showed that the engine operated normally.