Flight Overview
The accident took place on a survey flight from Nizhniye Kresty, which is now known as Cherski, to Pevek. The aircraft was conducting a survey of an icy continent.
Unauthorized Route Change
At some point during the flight, the captain left the cockpit and went into the passenger cabin. The copilot then made the decision to shorten the planned route without consulting the captain. This action was in direct contravention of all published procedures. As a result, the aircraft flew over Cape Shelagski, a hill with an elevation of 469 meters.
Impact and Crash
As the aircraft approached the cape, it encountered a strong downdraft. The downdraft caused the aircraft to lose altitude, and the lower part of the fuselage struck the hill. The impact was severe enough to throw the aircraft back into the air. Subsequently, the aircraft crashed into a large boulder and caught fire.
Rescue and Casualties
Three crew members were rescued from the wreckage. Seven other individuals who were on board lost their lives in the accident.
Probable Cause
According to the official investigation, the probable cause of the accident was the wrong decision made by the copilot. He modified the route without referring to the captain and in disregard of all established procedures.