45 fatalities

1970-04-01: Antonov AN-24 (CCCP-47751) — Aeroflot - Russian International Airlines — Toguchin, Russia

Toguchin, RussiaFlight

On April 1, 1970, an Antonov AN-24 (registration CCCP-47751) operated by Aeroflot - Russian International Airlines was involved in an aviation accident near Toguchin, Russia in flight. 45 people were killed. Investigators recorded the probable cause as: In-flight collision with a radiosonde weather balloon while cruising by night. Apparently, the crew has not been informed about the presence of the weather balloon. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 8 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781236476Data APIEditorial standards

An aircraft collided with a radiosonde weather balloon at night, causing cockpit destruction and loss of control. The crash killed all 45 occupants and destroyed the aircraft.

Accident Summary

An aircraft crashed in an open field 20 kilometers southeast of Toguchin after colliding with a radiosonde weather balloon at night. The accident resulted in the total destruction of the aircraft and the deaths of all 45 occupants.

Sequence of Events

The flight departed Novosibirsk-Tolmachevo Airport at 0342 local time. The crew was cleared to climb to 4,200 meters, an altitude reached at 0353. Subsequently, they were cleared to continue climbing to the assigned altitude of 6,000 meters. While flying at 5,400 meters, the aircraft collided with a radiosonde weather balloon operated by the Hydrometeorological Service. The balloon struck the windshield and nose cone, partially destroying the cockpit. The aircraft went out of control, entered a dive, and partially disintegrated at an altitude of 2,000 meters before crashing. The impact speed was 300 km/h. Some debris from the nose and the weather balloon were found more than 6 kilometers from the main point of impact. The windshield was not recovered.

Investigation Findings

The official investigation determined that the probable cause was an in-flight collision with a radiosonde weather balloon while cruising by night. The crew had apparently not been informed about the presence of the weather balloon.

Probable Cause

In-flight collision with a radiosonde weather balloon while cruising by night. Apparently, the crew has not been informed about the presence of the weather balloon.