What happened
On the morning of the accident, a Piper PA-31-350 Navajo Chieftain was conducting a visual flight rules (VFR) flight from Bear Valley, British Columbia, to Tsay Keh. The aircraft had previously arrived at Bear Valley from Mackenzie under instrument flight rules (IFR) to drop off a passenger.
While flying toward Tsay Keh, the pilot encountered heavy snowfall and significantly reduced visibility. In an effort to regain visual contact with the ground, the pilot executed a 180-degree turn. Shortly after completing this maneuver, at approximately 1055 Pacific standard time, the aircraft struck the ice on the Peace Reach Arm of Williston Lake. The impact, which occurred in a slight left bank, resulted in the destruction of the aircraft. The pilot, who was the sole occupant, sustained serious injuries.
The investigation
Investigators examined the wreckage at the crash site and found no evidence of mechanical failures or pre-existing deficiencies that would have caused the aircraft to lose altitude. The aircraft was reported to be functioning normally until the moment of impact.
Data from the scene indicated the aircraft hit the ice with its left propeller first, followed by the fuselage and the right propeller. The investigation also noted that the pilot had extensive experience, including 4,500 total flight hours, and was proficient in IFR operations. However, because the destination aerodrome lacked an IFR approach, the pilot was forced to attempt the leg under VFR conditions.
Findings
- The weather conditions at the time of the accident were unsuitable for maintaining visual flight.
- The pilot was unable to visually distinguish the frozen surface of the lake from the falling snow.
- The pilot allowed the aircraft to descend unintentionally while focusing on regaining visual references, leading to the collision with the ice.
- A lack of official weather reporting facilities at the departure point meant the pilot had to rely on informal reports from local personnel to estimate conditions.