What happened
During a nighttime survey operation originating from Petropavlovsk-Kamchatsky, a twin engine airplane was performing an approach toward Yuzhno-Sakhalinsk Airport. While flying at an altitude of approximately 850 metres, the aircraft impacted the slope of Mt Ostraya, which reaches an elevation of 910 metres. The collision occurred roughly 12.5 km from the destination airport.
Search efforts located the debris field three days after the initial impact. Of the eleven people on board, nine fatalities were recorded. Two passengers, identified as hydrologists, survived the crash and were recovered from the wreckage.
Findings
Investigations into the accident determined that a series of navigational mistakes by the crew caused the aircraft to follow an incorrect path during its approach to the airport. The investigation also noted that poor visibility and adverse weather conditions served as contributing factors to the flight's deviation from the intended track.