Accident
A single-engine airplane departed Okhotsk on a cargo flight to Severny in the Ayan district of the Khabarovsk region, carrying five oil barrels to supply an aerological expedition. En route, the crew encountered strong downdrafts while overflying the Dzhugdzhur Mountain Range. The airplane lost height and crashed at an elevation of 800 metres into the slope of a mountain 1,450 metres high, located 12 kilometres from the Severny Ui Airstrip.
Investigation
As the airplane failed to arrive at its destination, search and rescue operations were initiated. The burnt wreckage was found on June 4. Both pilots were killed.
Probable Cause
According to the official investigation, the probable cause was loss of control in-flight due to strong downdrafts while flying over mountainous terrain.