What happened
A cargo mission operated by Aeroflot was traveling from Stalino to Izhevsk, scheduled to make several intermediate stops including Kharkov, Voronezh, Penza, and Kazan. The aircraft was transporting 2,250 kilograms of zinc nitrate bottles. During the final segment of the flight between Kazan and Izhevsk, the crew notified air traffic control that a fire had broken out inside the cabin and requested an immediate diversion to the closest airfield.
In response to the emergency, the captain initiated a descent to a lower altitude with the intention of performing an emergency landing in an open field. During this maneuver, the aircraft type struck the ground, resulting in a massive explosion. The impact destroyed the plane entirely, and all four fatalities were recorded among the crew members.
Findings
Investigations revealed that several containers of zinc nitrate had broken during the flight, allowing the chemical to leak into the aircraft's heating system. When the crew activated the heat, the liquid reached its ignition temperature of 36° C, triggering the cabin fire.
Improperly secured hazardous cargo was identified as a primary factor, as the shipping company failed to follow safety protocols for transporting dangerous goods. Furthermore, the operator was not informed of the specific nature of the shipment, meaning the crew was unaware of the chemical risks on board. During the crash sequence, additional bottles ruptured and exploded, making the aircraft impossible to control.