7 fatalities

1975-09-30: De Havilland DHC-6 Twin Otter (CF-MHU) — Northern Thunderbird Air - NT Air — Kluatantan, Canada

Kluatantan, CanadaFlight

On September 30, 1975, a De Havilland DHC-6 Twin Otter (registration CF-MHU) operated by Northern Thunderbird Air - NT Air was involved in an aviation accident near Kluatantan, Canada in flight. 7 people were killed. Investigators recorded the probable cause as: The accident was the consequence of the following factors: - The pilot continued the flight along a narrow valley into deteriorating weather conditions below the altitude required for safe terrain clearance. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 4 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781229790Data APIEditorial standards

On a scheduled passenger and cargo flight, an aircraft crashed into a ridge at 5,200 feet after encountering poor weather. All seven occupants died. The investigation cited continued flight into deteriorating weather, an ineffective windshield wiper, and failure to maintain climb.

Accident Overview

On a scheduled flight transporting passengers and cargo from Prince George to Dease Lake via intermediate points, the aircraft operated under visual flight rules (VFR). Shortly after takeoff from Kluatantan airstrip, the flight encountered poor weather. Approximately 23 miles north of the takeoff point, the aircraft crashed against the side of a ridge at an elevation of 5,200 feet. The impact forces and a post-crash fire destroyed the airplane. All seven occupants were killed.

Investigation and Probable Cause

According to the official investigation, the accident resulted from multiple factors. The pilot continued the flight along a narrow valley into deteriorating weather conditions below the altitude required for safe terrain clearance. Forward visibility was hampered by an ineffective windshield wiper system. After losing visual references, the pilot attempted to obtain safe terrain clearance by climbing into the cloud layer. For undetermined reasons, the pilot did not initiate or maintain a maximum rate of climb to clear enroute terrain. Additionally, accurate and updated presentations of forecast or actual weather conditions in the accident area were not available to the pilot prior to departure from Prince George, due in part to the lack of reporting points.