An-2T Emergency Landing in Marsh Area Near Vilyuisk (RA-01419)

Incident Overview and Flight Details On a scheduled service flight (flight number PI9977) from Vilyuisk Airport to Kyubeinde-Ugulet, an An-2T aircraft with registration RA-01419 experienced an engine malfunction shortly after takeoff. While cruising at an altitude of approximately 400 meters, the engine overheated and lost power as oil pressure dropped. The crew decided to return to Vilyuisk, but the engine failed completely shortly thereafter, forcing an emergency landing. The captain selected a swampy area located 26 kilometers northwest of Vilyuisk (coordinates N63°54.584' E121°18.048') for the landing. During the touchdown, the main landing gear became stuck in the soft ground, causing a dynamic pitch-down moment. The engine struck the ground and was ripped from the airframe, resulting in the separation of the fuselage along the engine mounting fitting. The aircraft came to rest and immediately burst into flames, ultimately being totally destroyed by the fire. Despite the severity of the crash, both pilots and all nine passengers escaped the aircraft uninjured. ## Probable Cause and Contributing Factors The official investigation determined that the accident was caused by the emergency landing in a marsh area selected from the air, which resulted in the main landing gear dipping into soft ground. This led to a dynamic pitch-down moment, engine ground impact, and subsequent fuselage separation. The fire, which almost completely destroyed the aircraft, was caused by the destruction of the gasoline pipeline during engine separation and the ingestion of fuel onto hot parts of the power unit. The investigation also noted that the pilot-in-command's failure to turn off the ignition and shut off the fuel before landing may have contributed to the fire. The initial emergency landing was necessitated by an increase in oil temperature and a drop in oil pressure below the values specified in the aircraft's Flight Operations Manual. However, due to the substantial damage to engine components caused by the fire, it was not possible to determine the specific cause of the temperature increase and pressure drop.