What happened
On the scheduled flight from Edmonton to Port Radium, NWT, via Fort Smith and Yellowknife, the aircraft began its journey at 11:37 local time. While initially climbing to 9,000 feet, the crew encountered light rime ice between Edmonton and Fort McMurray, which the onboard deicing systems managed effectively. However, shortly after passing Fort McMurray at approximately 13:20, the aircraft entered an area of freezing rain.
In an attempt to rejoin the airway toward Fort Smith, the flight path was diverted toward Embarras. During this period, ice began accumulating on the airframe at a rate that exceeded the capacity of the deicing equipment. The crew attempted to descend to 7,000 feet to mitigate the conditions, but further ice collection occurred during the descent. As the aircraft struggled to maintain altitude, dropping to 5,000 feet while navigating rain squalls, it encountered severe turbulence at approximately 4,500 feet.
The combination of heavy ice buildup and intense turbulence led to a significant loss of altitude, resulting in a collision with trees. The pilot executed a forced landing at 13:52 local time. The impact resulted in two serious injuries and the total destruction of the aircraft.
Findings
Investigations determined that the primary reason for the accident was that the flight continued into an area characterized by freezing precipitation. This led to rapid ice accumulation and severe turbulence, which caused a partial loss of control and the subsequent impact with trees. Additionally, the weather conditions encountered were significantly more intense than what had been predicted in the original forecast.