Flight History
The aircraft was on a return flight between Resolute Bay, Nanisivik, and Pond Inlet. The first two legs had been completed, and the aircraft was refueled at Pond Inlet. The return flight to Nanisivik was flown at 8,000 feet, and all reports and radio transmissions were routine.
Accident Details
The last transmission to the radio operator at Nanisivik, made by the First Officer, stated that the aircraft was "a couple of miles back on left base and will be turning final shortly," indicating a night visual approach. A final wind check was passed to the aircraft but no acknowledgement was received. A witness described the aircraft as "moving in a violent fashion" before it crashed 2,200 feet short of the runway in a 45° nose-down, 80° right-bank attitude. All eight occupants were killed.
Investigation
Examination of the weather aftercast indicated that low-level turbulence and vertical windshear of 10 to 12 knots per thousand feet existed at the time of the accident. Other aircraft reported varying degrees of turbulence on final approach both before and after the accident. Technical investigation suggested that the right engine was rotating at or below flight idle at impact. Extensive laboratory analysis of the engine components failed to prove conclusively that an engine failure had actually occurred, and until further evidence is forthcoming, the accident cause must remain undetermined.
Aftermath
Thirteen months after the accident, evidence began to emerge regarding possible in-flight failure of DHC-6 flap and aileron control rods. A failed flap rod was recovered from Vancouver Harbour on 26 January 1979, and a failed aileron rod was recovered at Sechelt, B.C., on 30 September 1979, from two aircraft that had crashed under very similar circumstances to CF-ABW. This led to a decision to reopen the investigation. Negotiations and financial arrangements to recover and re-examine the buried aircraft structure were initiated in February 1980, with a target date between mid-July and mid-August. However, as the aircraft had been burned, crushed by a bulldozer, partially scattered, and buried under 20 feet of shale in the Nanisivik dump, the projected recovery attempt was deemed futile. This decision was made on 17 July 1980. The safety deficiency related to stress corrosion control rod failure had been identified and rectified by Airworthiness Directive (AWD) action as a result of subsequent DHC-6 accidents, so no useful accident prevention purpose would be served in pursuing this accident further.