Overview
An aircraft operating a flight from Yuzhno-Sakhalinsk to Khabarovsk crashed in a mountainous and isolated area of the Sikhot-Alin Mountain Range. The aircraft was cruising at an assigned altitude of 10,600 metres when it rolled to the right, entered an uncontrolled descent, and impacted terrain. The aircraft disintegrated on impact, and all 98 occupants were killed.
Flight and Accident
Approximately 35 minutes after takeoff, while cruising at the assigned altitude, the aircraft suddenly rolled to the right and began an uncontrolled descent. The crash occurred in a remote, mountainous region. Search and rescue (SAR) operations were initiated but suspended a day later due to deteriorating weather conditions. They resumed four days later. The wreckage was located 11 days after the accident, about 50 kilometres west of Grossevichi.
Investigation
An investigation was conducted to determine the cause of the accident. The official findings identified that the crew had selected the left main fuel tank to feed all three engines after takeoff from Yuzhno-Sakhalinsk. During the first 35 minutes of flight, the automatic pilot system was able to control and counteract the imbalance caused by asymmetric fuel consumption from the left tank. Eventually, the aircraft began to bank to the right. The crew's reaction to the unexpected situation was non-compliant, which caused the aircraft to enter an uncontrolled descent.
Probable Cause
The probable cause, as stated in the official investigation, was that the crew selected the left main fuel tank to feed all three engines after takeoff. The autopilot counteracted the resulting imbalance for 35 minutes, but when the aircraft banked right, the crew's non-compliant reaction led to an uncontrolled descent.