Date & Time: Apr 12, 1995 at 0843 LT
Sioux Falls - Fargo
Crew on board:
Pax on board:
Captain / Total hours on type:
Aircraft flight hours:
The airplane was cruising at 6,000 feet where it encountered icing conditions. When cleared to 3,600 feet, the pilot reported that one engine lost all power and the other one was running rough. The airplane continued the descent. After about ten minutes the airplane departed controlled flight, reversing heading and impacting near vertically in the terrain. A post accident examination of the left engine (which was feathered) found an induction duct which had deteriorated and begun to come apart. Foreign object material in the compressor assembly similar in appearance to material from the duct was found. The number five piston had a hole burned through it.
The pilot/mechanic's inadequate maintenance (inspection) of aircraft and the pilot's failure to maintain airspeed (VMC). Factors were icing conditions, deteriorated induction air ducting, and failure of a piston assembly.