What happened
During an approach to Yuzhno-Sakhalinsk from the southeast, the flight encountered difficult weather characterized by low cloud cover. While flying at an altitude of approximately 400 meters, the aircraft type struck treetops before crashing in an inverted position. The impact occurred within a forested area on the slope of Mt Komissarskaya, situated roughly 13.5 km southeast of the destination airport.
The wreckage was located the following day. Of the 27 people on board, 26 fatalities were recorded, while one passenger survived the crash with serious injuries. The impact resulted in the total destruction of the aircraft.
Findings
Investigations into the accident identified several contributing elements. A primary factor was a navigational error where the radio navigator incorrectly identified two outer markers. Specifically, the crew utilized the marker for the Korsakov Airbase (684 kHz) instead of the intended marker for Yuzhno-Sakhalinsk-Bolchaya Yelan (670 kHz). This error was facilitated by the close proximity of the two markers, which are separated by only 13.5 km, and their similar frequencies.
Additional contributing factors included:
- Reduced visibility due to low clouds, which prevented the crew from identifying the mountain.
- A failure to utilize the radio altimeter during the approach.
- Improper use of the direction finder unit by the crew.