What happened
On the morning of January 4, 2007, a Cessna A1-85F, registration C-GSDJ, departed Yellowknife, Northwest Territories, for a chartered flight to Blatchford Lake Lodge. The aircraft, operated by Arctic Sunwest Charters, was carrying a pilot and three passengers along with supplies and gear. During the flight, the aircraft encountered freezing fog and moderate mixed icing, as forecasted for the destination area.
As the flight progressed, the aircraft's altitude decreased, and the pilot began a descent toward the lodge. GPS data later revealed that the aircraft's path deviated from the intended waypoint, eventually turning northeast away from the destination. The aircraft entered a left turn at a low altitude and began to shake before a sudden descent and impact on the frozen surface of Blatchford Lake. The crash resulted in two fatalities and one serious injury, while the fourth occupant survived. The aircraft sustained substantial damage.
The investigation
The investigation focused on the aircraft's flight path, the environmental conditions, and the pilot's adherence to operational procedures. Investigators recovered a hand-held GPS, which provided track log data showing the aircraft's ground speed and altitude fluctuations. The analysis revealed that the aircraft's center of gravity was at or slightly aft of the aft limit.
Investigators also examined the aircraft's configuration and the pilot's training. It was noted that the aircraft was not equipped or approved for flight in icing conditions, yet the pilot continued the flight after reporting rime ice. Furthermore, the investigation looked into the lack of an emergency locator transmitter (ELT) signal, which delayed search and rescue efforts. It was determined that the ELT's activation switch was oriented in a way that prevented it from triggering during the vertical impact.