What happened
The pilot was flying an enroute leg to Ellen Church Field, a flight that lasted approximately 2-1/2 hours. Upon arrival at Ellen Church Field, the pilot visually inspected the fuel levels in each wing tank and noted they were just below the tabs; no additional fuel was obtained at that time.
During the return flight to Columbus Municipal Airport, the pilot maintained a cruise altitude of 3500' msl with the power set to 2300 rpm and the mixture control retarded 1/4'. While the flight progressed as scheduled for the first two hours, the subsequent progress was slower than planned. The fuel gauges then indicated 1/4 fuel remaining in each tank. During this period, moonlight was visible from the left side of the aircraft, while lightning was visible from the right.
The engine stopped running, and the pilot noted that the left tank was empty. He selected the right fuel tank to attempt an engine restart. Estimating only twelve minutes of fuel remaining in the right tank, the pilot searched for a landing area. Due to thunderstorms located between his position and Sioux Gateway Airport near Sioux City, Iowa, the pilot decided to land on a blacktop road. During the landing sequence, the aircraft impacted a pole. The pilot did not attempt to initiate a climb during the impact because he was uncertain of the condition of the flight controls.
The investigation
Federal Aviation Administration (FAA) inspectors examined the aircraft and found that all fuel caps and fuel sump valves were in the closed position. Although the engine had stopped, investigators observed that fuel was still present in the left tank. The fuel selector was found to be set to the left tank. Additionally, the FAA confirmed that the pilot had received a briefing regarding convective activity for the intended route of flight.