Accident Details
On the day of the accident, the aircraft departed from Pemberton Airport, British Columbia, at approximately 1500 Pacific daylight time, on a visual flight rules flight to Edmonton, Alberta. The pilot, the sole occupant, was repositioning the aircraft after conducting air quality surveys for Environment Canada’s Air Quality Research Section. About 30 minutes after takeoff, the Coastal Fire Service responded to a spot fire and discovered the aircraft wreckage within the fire zone. The accident occurred at about 1506 Pacific daylight time. A post-crash fire consumed most of the airframe, and the pilot was fatally injured.
Aircraft Information
The aircraft was operating on a flight permit and was highly modified to accommodate various types of probes in equipment pods suspended under the wings, a camera hatch in the centre belly area, and internal electronic equipment. The modifications were for its role in environmental research.
Probable Cause
The investigation determined that the pilot entered the valley at an altitude above ground that did not provide sufficient terrain clearance given the aircraft’s performance. The pilot encountered steeply rising terrain, where false horizon and relative scale illusions in the climb are likely. Realizing that the aircraft would not likely be able to out-climb the approaching terrain, he turned to reverse his course. The aircraft’s configuration, relatively high weight, combined with the effects of increased drag from the equipment, density altitude, down-flowing winds, and manoeuvring resulted in the aircraft colliding with terrain during the turn.