What happened
A scheduled flight traveling from Vaernes Airport in Trondheim toward Oslo departed at 08:30 local time carrying ten passengers and a crew of two. Shortly after takeoff, the aircraft type entered cloud cover at an altitude of 2,500 feet, losing all visual contact with the ground. During the climb to cruising altitude between Vaernes and Tolga, the co-pilot noted that while cruise power was applied, the indicated airspeed remained 20 knots lower than expected.
At 09:12, the aircraft passed the Tolga radio beacon at 8,000 feet, reporting light icing. This served as the final communication from the flight. Following this contact, icing conditions intensified rapidly, causing the aircraft to lose altitude despite the active use of de-icing systems on the wings and tail. At 09:25, a decision was made to divert back to Vaernes Airport.
During the flight, near Tolga, the captain altered the course 25 to 30 degrees northeast. The co-pilot believed this maneuver indicated a diversion to Rhos, leading the co-pilot to take control of the aircraft while the captain attempted to re-establish radio contact on frequency 126.7 mc/s. No communication was successful.
At approximately 09:50, the aircraft struck Hummelfjell at an altitude of roughly 1,350 meters. The flight was operating in heavy fog, and ice accumulation on the cockpit windows had severely limited visibility for the crew. The impact occurred in a terrain depression, where the plane bounced twice on a 40 cm layer of snow before coming to a rest. The accident resulted in 2 fatalities, including the captain and one passenger.