What happened
Prior to the accident, the aircraft had completed a 3.5-hour flight, consuming approximately 156 gallons of its 196-gallon usable fuel capacity. Following this flight, the aircraft was refueled with 156 gallons. However, during the preflight inspection, a ground crew member noticed that the right main fuel tank sump had become stuck in the open position. This resulted in an estimated loss of 5 to 6 gallons of fuel, though the precise amount remained unverified. This lost fuel was not replenished before the aircraft departed for its return leg.
GPS data shows the aircraft maintained an altitude of roughly 4,500 feet MSL for approximately 4 hours. During the descent toward the intended destination, the pilot requested a diversion to a nearer airport. While executing an approach to runway 18R at this new location, the pilot notified air traffic control that the engines had run out of fuel. The aircraft type crashed into a wooded area roughly 0.5 miles from the airport. Post-accident investigations of the engines and propellers showed no mechanical failures or evidence of engine rotation at the moment of impact.
Findings
Investigation revealed that the aircraft's fuel reserves were insufficient to complete the extended flight duration. The combination of the fuel lost during the preflight sump malfunction and the additional flight time required for the return leg depleted the usable fuel. The pilot did not report any issues regarding the fuel state prior to the exhaustion announcement. It was noted that the decision to approach runway 18R instead of 18L added at least one mile to the flight path.
Toxicology reports indicated the presence of cyclobenzaprine and diphenhydramine in the pilot's system at therapeutic levels. Because these medications can impair the mental and physical functions necessary for flight, it is believed that the pilot's impairment prevented the recognition of the low fuel state.