Douglas C-54 Skymaster

The purpose of the flight was to transport 3,400 gallons of unleaded fuel and two 100-gallon propane tanks from Fairbanks International Airport (FAI), to Kobuk Airport (OBU), Kobuk, Alaska. The airplane departed about 0955. An eyewitness reported seeing the airplane flying to the west and stated that the far left engine was not running. They also noticed a small, white plume of smoke coming from that engine. The airplane started to turn to the south, and at that point he noticed that the engine was on fire. About three minutes after departure, the pilot reported to air traffic control that there was a fire onboard and began a left turn back to the airport. Video surveillance showed white smoke begin to develop behind the No. 1 engine, followed by flames. Seconds later, a bright white explosion could be seen just behind the No. 1 engine. The airplane then entered an uncontrolled, descending left turn into terrain. The No. 1 engine separated from the wing about 100 ft above the ground and landed on a frozen river. About two minutes later, the video showed a large explosion. The University of Alaska Fairbanks (UAF) detected multiple low frequency sound (infrasound) signals associated with the accident. Based on the data collected by UAF, the first explosion was at 1001, the airplane impacted terrain at 1003, and the second explosion was at 1006. The airplane was totally destroyed by impact forces and a post crash fire and both crew members were fatally injured.

Following an uneventful cargo flight from Christiansted-Henry E. Rohlsen Airport, the crew completed the landing normally at San Juan-Luis Muñoz Marin Airport. While taxiing to the ramp, the nose gear collapsed and the aircraft came to rest. Both pilots escaped uninjured and the aircraft was damaged beyond repair.

The flight crew was delivering a cargo of fuel in the four-engine airplane under Title 14, CFR Part 125, when the airplane lost power in the number 2 engine. The captain elected to shut the engine down and return to the airport. He said during the shutdown procedure, the engine caught fire, and that the fire extinguishing system was activated. The crew thought the fire was out, but it erupted again, and the captain elected to land the airplane gear-up on the snow covered tundra. Once on the ground, the left wing was consumed by fire. An inspection by company maintenance personnel revealed that an overhauled engine cylinder had failed at its base, resulting in a fire. The airplane was not examined by the NTSB due to its remote location.