Accident Details
The aircraft was completing a cargo flight from Fairbanks to Dietrich Camp with an intermediate stop in Bettles, carrying a load of 6,800 gallons of fuel. While flying to Bettles Airport under night conditions and encountering moderate turbulence, the airplane went out of control and crashed in an isolated area at Old Man's Camp, approximately 31 miles southeast of Bettles Airport. The aircraft was totally destroyed and all four crew members were killed.
Investigation Findings
The official probable cause of the accident was determined to be an in-flight airframe failure following inadequate maintenance and inspection. The following contributing factors were reported: engine structure issues, separation in flight, fatigue in fastener holes in the lower hat section, skin panels, the No. 3 engine compressor diffuser case, and a separation of the right wing. The investigation concluded that these factors led to the structural failure of the aircraft in flight.