Mid-air collision over Surgut (1967)

The collision over Surgut was an aviation accident that occurred on Sunday 2 July 1967, when an An-2 aircraft and a Mi-6 helicopter collided in the Surgut area; 9 people were killed. The An-2 fell into a swamp after losing control. The Mi-6, despite damage, made an emergency landing, and all 5 people on board survived.

Crash

The Mi-6 crew was serving an expedition and was flying from Tyumen to Ust-Balyk with an intermediate stop in Tobolsk. At 12:05 local time aircraft 11289 took off from Tyumen and at 13:10 landed safely in Tobolsk. Then at 13:45 the helicopter took off for Ust-Balyk; only the crew was on board. According to the weather forecast received by the crew before departure, on the sector from Surgut to Tobolsk the sky was almost completely covered with cumulonimbus and fractonimbus clouds with a base of 200—300 metres, brief rain, thunderstorm condition, and visibility reached 6—10 kilometres. But already by 14 o'clock in the area of Ust-Balyk, which was 20 kilometres north-west of the axis of the Surgut — Tobolsk route, the weather began to deteriorate rapidly, and at 14:25 the weather service in Surgut reported to the Surgut Airport control centre that the cloud base had dropped to 130—180 metres.

At this time, in Surgut itself, a military An-2 was preparing for departure, which was to perform a cargo-passenger flight to Tyumen (according to some data, to search for the first stage of a ballistic missile). Despite the deterioration of the weather, the controller did not prohibit the flight, so at 14:50 the military aircraft, with 6 passengers, 3 crew members and 300 kilograms of cargo on board, took off from Surgut. At 14:55, while maintaining contact with the aerodrome control service, the pilots switched to communication with the Surgut area control service and reported flying visually at an altitude of 200 metres, and at 15:07 received confirmation from the controller that they were on track, as well as permission to leave the airport zone.

Because the weather continued to deteriorate, at 15:14 the controller instructed the Mi-6 crew to proceed to Surgut, since the cloud height over Ust-Balyk had already dropped to 150 metres, because of which Ust-Balyk airport was closed due to weather conditions. The instruction to return to Surgut was not passed to the light aviation aircraft that had taken off earlier, including the military aircraft. In fact, the aircraft and the helicopter were now flying towards each other, and at the same altitude, and their crews did not even suspect it.

At 15:32 the Mi-6 was flying at an altitude of 150—170 metres and was 112 kilometres south-west (azimuth 210°) of Surgut Airport (near the present-day town of Pyt-Yakh), when its co-pilot Ivanov suddenly saw the An-2 flying straight at them. Captain Semenyuk had not yet noticed the danger, but the co-pilot immediately took over the controls, after which he sharply dropped the "collective pitch—throttle" and then sharply banked the helicopter to the left. But because of the short distance the collision could no longer be avoided, so a few seconds later the blades of the huge main rotor (35 metres in diameter) of the banked helicopter struck the aircraft and chopped off the outer part of its upper right wing, and also destroyed its propeller. Having lost control, the An-2 turned over and, going into an almost vertical fall, crashed into a swamp and was completely destroyed, partially burying itself in the soft ground. All 9 people on board were killed. The helicopter sustained damage to the blade tips as well as to the 25th and 26th sections, but remained controllable and soon landed safely in Surgut. No one on board was injured.