What happened
During the second leg of a cross-country flight, the pilot departed with an estimated 82 gallons of fuel on board. Approximately three hours and 30 minutes into the flight, while the landing gear was down and locked and the aircraft was turning from the downwind to the base leg, the pilot noticed a vibration originating from the left side of the aircraft. An attempt to lower the flaps was unsuccessful, confirming that the left engine had failed.
Due to being high and fast without the use of flaps, the pilot elected to continue the approach and land. However, near the approach end of the runway, the right engine also failed. The pilot attempted to force the aircraft onto the runway, which caused several bounces. The aircraft made firm contact with the runway but subsequently overran the end of the runway, crossed an irrigation ditch, and came to rest upright in an onion field.
The investigation
A post-accident investigation of the four fuel tanks on the aircraft revealed that the right auxiliary, right main, and left main fuel tanks were empty. Only the left auxiliary fuel tank contained approximately 2 inches of fuel.
Findings
The investigation found no mechanical anomalies with the aircraft that would have prevented normal operation. The pilot reported encountering high winds while en route to the destination but stated he was unaware of how the fuel had been depleted.