What happened
Following its departure from Sovietskaya Gavan Airport, the flight was cleared to proceed at a designated altitude of 2,700 meters. During the transit, the aircraft encountered increasingly difficult weather conditions characterized by heavy cloud cover, turbulence, and strong northern winds reaching speeds of 90 km/h.
As the aircraft traversed the Sikhote-Alin Mountain Range, it was caught in powerful downdrafts that forced a loss of altitude. In an attempt to recover height, the crew increased engine power; however, the descent continued despite these efforts. The aircraft eventually collided with the slope of Mt Tordoki-Yani, which stands at 1,750 meters, striking the terrain approximately 20 meters below the peak. Search teams located the wreckage on December 21, 1955. There were 21 fatalities and no survivors.
Findings
Investigations concluded that the primary factor in the accident was a severe downdraft that caused the aircraft to lose sufficient altitude to strike the mountain slope.