What happened
The crew was operating a scheduled cargo flight originating from Moscow with the final destination of Karaganda. The route included intermediate stops at Kazan, Chelyabinsk, and Kostanay. The aircraft was transporting a mixed load of industrial goods, including an industrial furnace, theater sets, brass tubes, and electrical equipment.
During the night cruise phase at an altitude of 1,800 meters, the flight engineer observed flames emanating from the left engine. Following initial checks and tests, the captain reduced the aircraft's altitude to 1,500 meters but ultimately decided to continue the journey rather than divert. Approximately one hour later, while climbing to or maintaining an altitude of 3,000 meters, the left engine suffered a total failure.
With only one engine operational, the pilot was unable to maintain a safe flight path. The aircraft descended and struck treetops before crashing into a wooded area situated on a hilltop. The impact site was located approximately 22 kilometers east of Mourom and 12 kilometers north of Savasleyka. Three crew members were killed in the accident, while a fourth sustained serious injuries.
Findings
The official investigation determined that the primary cause of the accident was the failure of the left engine. This failure resulted from the rupture of a flexible hose on a hydraulic line, which interrupted proper engine lubrication. It was established that this hose had been improperly secured during a maintenance procedure conducted in April.
Contributing factors to the disaster included the lack of visibility due to night conditions and a critical decision-making error by the crew. The team chose to continue the flight after observing the initial engine anomaly an hour prior to the total failure, rather than taking immediate corrective action.