Incident Overview
On the day of the accident, Flight 3 was operating a scheduled route from Anchorage to Shemya, with intermediate stops at Cold Bay and Adak, Alaska. After a routine takeoff from Cold Bay, the flight made all en route radio reports to the company within two to three minutes of their estimated times. At 1650 local time, the flight reported its position as 100 miles northeast of Adak at an altitude of 4,500 feet, on top and in the clear. The crew estimated arrival over the Adak low frequency range at 1725 LT.
Communications and Flight Plan Changes
Air traffic control cleared the flight to the Adak low frequency range, instructing them to maintain visual flight rules (VFR) on top and to contact Adak approach control when 30 miles out for landing instructions. At 1715 LT, the flight advised the company that it was canceling its IFR flight plan and proceeding VFR. Two minutes later, Flight 3 attempted to communicate with Adak approach control. Approach control responded to the call but was unable to establish contact with the flight.
Accident Details
Subsequent investigation determined that the aircraft had crashed into the northeast side of the Great Sitkin volcano, which has an elevation of 1,740 meters and is located on Great Sitkin Island, approximately 25 miles northeast of Adak Airport. The aircraft was destroyed, and all 16 occupants were killed.
Probable Cause
Official findings from the investigation state that the probable cause of the accident was the captain's failure to maintain flight in accordance with visual flight rules during a descent over hazardous terrain.