Incident
On December 9, 1977, a corporate jet HS-125 departed Montreal at 2123 GMT with Churchill Falls as its destination. The estimated flight time was 1 hour 45 minutes. The flight proceeded normally and remained in contact with air traffic services en route. As the aircraft approached Churchill Falls, the crew received clearance for the approach from Moncton ATC. At 2228 GMT, the pilot acknowledged the clearance and received the latest weather information. The aircraft left cruising altitude shortly thereafter, and the descent was normal to the minimum initial altitude for the instrument approach. The flight reported outbound to Churchill Falls advisory at approximately 2252 GMT. The final transmission from the crew indicated they were two miles back on final approach and could see the strobe lights and the visual approach slope indicator system (VASIS).
Search and Rescue
Moncton Centre was alerted shortly after 2300 GMT when it became evident that the aircraft had not landed. A local search was initiated with two helicopters from the airport, but due to deteriorating weather, the search had to be discontinued, and the aircraft was not found that night. Search and rescue teams were alerted at 2314 GMT. Near-blizzard conditions occurred that night and continued into the next day, December 10. It was not until December 11 that the air search was resumed, and the aircraft was located two miles short of the threshold of runway 14. There were no signs of life.
Probable Cause
The official investigation determined that the accident was the consequence of the combination of the following findings: cockpit discipline was inadequate as the approach entered the final phase; distractions in the cockpit degraded crew performance; the pilots deprived themselves of essential altitude information by not effectively monitoring the flight instruments during the final approach; the captain, by relying on visual cues from the runway environment lighting in conditions where those cues were degraded, became exposed to visual illusions; the pilots permitted the aircraft to deviate below the safe approach profile until it struck the terrain; and on the assumptions that there had been at least one serviceable emergency locator transmitter (ELT) on board, that it had been activated as a result of the impact or by other means, and that there was the capability at Churchill Falls of homing to the point of origin of the ELT signal, the rescue activity may have been expedited.