Incident Overview
A passenger aircraft, while parked on the apron at Sofia-Vrazhdebna Airport, was deiced and snow was removed from its surfaces. After the crew received clearance to taxi to runway 10 for takeoff, the runway was temporarily closed for additional snow removal. Once the runway was reopened, the crew was cleared for takeoff. Immediately after liftoff from runway 10, the airplane encountered difficulties gaining altitude, stalled, and crashed on a bank of the Iskar River near the airport.
Casualties and Rescue
The copilot was killed in the crash. Two passengers drowned. All other occupants were rescued, some of whom sustained injuries.
Probable Cause
The official investigation determined that the holdover time (HOT)—the period between deicing and takeoff—was too long, allowing a significant accumulation of snow on the fuselage, wings, and all critical surfaces. In such contaminated conditions, the aircraft was unable to achieve sufficient lift for takeoff. The crew failed to request a second deicing procedure before departure.