What happened
A flight departing from Kostroma Airport at 07:30 local time was engaged in an aerial photography mission along a railroad route spanning from Neya to Svesha, passing through Manturovo and Sharya. The aircraft was carrying seven crew members and one passenger at the time of the incident.
During the mission, approximately two hours and ten minutes after takeoff, the left engine experienced a failure. Shortly following this initial malfunction, the right engine began to overheat. In response to these escalating mechanical issues, the pilot attempted to divert the flight to Sharya. However, as the aircraft lost altitude, it struck trees and came to rest in a dense forest area near km 711, roughly 600 meters from the railway tracks.
The impact resulted in the total destruction of the aircraft. While the passenger escaped without injury, all seven crew members sustained injuries. Tragically, the captain passed away eighteen hours after the accident due to the injuries sustained during the crash.
Findings
Investigations determined that the primary cause of the accident was a carburetor malfunction which led to the failure of the left engine. Additionally, high ambient temperatures were identified as a contributing factor, as these conditions prevented the crew from successfully maintaining a safe flight altitude while operating on only one functional engine.