1977 Tavda mid-air collision. The 1977 Tavda mid-air collision was an aviation accident that occurred on Saturday, May 7, 1977, when two An-2 aircraft operated by Aeroflot collided in mid-air near Tavda Airport, resulting in the deaths of 29 people.

Aircraft and Crews 
The An-2 with the serial number 114847316 and tail number СССР-15925 from the 1st Tyumen Combined Aviation Detachment of the Tyumen Civil Aviation Directorate was manufactured on November 2, 1960. It had accumulated a total of 17,514 flight hours and 17,391 cycles (landings). It was piloted by a crew from the 246th flight detachment, consisting of aircraft commander Alexander Filippovich Chagin and co-pilot Sergey Alexandrovich Baev.

The An-2TP with the serial number 1G27-15 and tail number СССР-44992 from the 2nd Sverdlovsk Combined Aviation Detachment of the Ural Civil Aviation Directorate was manufactured on December 28, 1962. It had accumulated a total of 16,932 flight hours and 16,482 cycles (landings). It was piloted by a crew from the 123rd flight detachment, consisting of aircraft commander Gennady Dmitrievich Borisenko and co-pilot Yuri Alexandrovich Shcheklein.

Circumstances Leading to the Accident 
On the day of the accident, the An-2 with tail number 44992 was operating flight Щ-801 on the route from Sverdlovsk to Turinskaya Sloboda, Turinsk, Tabory (Tabory District), Tavda, and Tyumen. After departing from the Uktus Airport in Sverdlovsk at 11:14, flight 801 landed at Turinskaya Sloboda. At 11:22, it took off again and headed toward Turinsk. However, it encountered difficult meteorological conditions en route, with visibility dropping below the meteorological minimum. As a result, the crew returned to Turinskaya Sloboda. Once the weather improved, a decision was made to alter the flight path to head directly to Tavda, bypassing Turinsk and Tabory. At 12:35, flight 801 took off again, landing at Tavda Airport at 13:02.

At 11:33 Moscow time (13:33 local time), the An-2 with tail number 15925 departed from Plekhanovo Airport in Tyumen, operating an additional flight 397 to Tavda. It carried 2 crew members and 13 passengers, including 2 children. According to the weather forecast received by the crew, the route was expected to have medium continuous cloud cover and variable cloud cover at 150–200 meters, rain, visibility of 2 to 4 km, and light winds. These weather conditions were above the meteorological minimum. However, no flight plans or departure information for flight 397 were relayed to Tavda.

At 11:56 Moscow time, the crew of aircraft 15925 contacted the Command and Control Point (KDP) of the Local Air Lines at Tavda Airport and reported flying from Tyumen at an altitude of 200 meters, with an estimated landing time of 12:07. At the same time, two other An-2 aircraft, for which no flight plans or departure information had been received at Tavda, entered the Tavda airport zone from Tyumen with only a 3-minute interval between them (with visibility less than 4 km, this interval should have been 10 minutes).

Collision 
Meanwhile, at 13:53, aircraft 44992 took off from Tavda Airport bound for Tyumen, carrying 2 crew members and 12 passengers, including 2 children. According to the weather forecast received by the crew, the route was expected to have continuous medium cloud cover and variable stratocumulus clouds at 400–600 meters, rain, mist, visibility of 6 to 10 km, and moderate turbulence. The dispatcher cleared aircraft 44992 to exit the airport zone at an altitude of 150 meters following Visual Flight Rules (VFR). Unaware of the approaching aircraft, the Tavda airport dispatcher left his post for 20 minutes. The approaching aircraft crews received approach conditions, weather at Tavda Airport, and the departure time of aircraft 44992 from the ground channel radio operator.

The aircraft, flying towards each other, most likely entered a zone where rain mixed with snow was falling, with cloud cover at 150–200 meters and visibility around 2 km. At 14:02 (12:02 MSK), 200–300 meters south of the village of Novoselovka (Sverdlovsk Oblast) (Tavda District) and 18 km south of Tavda Airport (azimuth 186°), aircraft 15925 and 44992 collided at an altitude of 175 meters. The left wing sections of both aircraft impacted each other, resulting in a loss of control and subsequent crashes 392 meters apart in a field. All 29 people on both aircraft perished.

Causes 
According to the commission's conclusions, the accident was caused by inadequate flight safety measures on local air routes in the Tyumen and Ural Civil Aviation Directorates, the absence of the Tavda airport dispatcher from his post, and the sudden encounter of the crews with adverse weather conditions that complicated visual flight operations. The commission members were divided on which cause (the absence of the air traffic controller from his post or the adverse weather conditions) was the primary cause and which was secondary.

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Aeroflot
May 1977
1977 meteorology
Mid-air collisions involving airliners
Mid-air collisions in Asia
Aviation accidents and incidents caused by weather
Aviation accidents and incidents caused by air traffic controller error