On 11 August 1979, a

mid-air collision In aviation, a mid-air collision is an aviation accident, accident in which two or more aircraft come into unplanned contact during flight. Owing to the relatively high velocities involved and the likelihood of subsequent impact with the ground o ...

occurred over the

Ukrainian SSR The Ukrainian Soviet Socialist Republic ( uk, Украї́нська Радя́нська Соціалісти́чна Респу́бліка, ; russian: Украи́нская Сове́тская Социалисти́ческая Респ ...

, near the city of Dniprodzerzhynsk (now

Kamianske Kamianske ( uk, Кам'янське, ), formerly Dniprodzerzhynsk, is an industrial city in Dnipropetrovsk Oblast of Ukraine and a port on the Dnieper. Administratively, it serves as the administrative center of Kamianske Raion. Kamianske hosts ...

). The aircraft involved were both Tupolev Tu-134As on scheduled domestic passenger flights, operated by

Aeroflot PJSC AeroflotRussian Airlines (russian: ПАО "Аэрофло́т — Росси́йские авиали́нии", ), commonly known as Aeroflot ( or ; russian: Аэрофлот, , ), is the flag carrier and the largest airline of Russia. The ...

. All 178 people aboard both aircraft died in the accident. The Soviet aviation board investigating the accident concluded that the crash was caused by "mistakes and violations" made by

air traffic controller Air traffic control specialists, abbreviated ATCS, are personnel responsible for the safe, orderly, and expeditious flow of air traffic in the global air traffic control system. Usually stationed in air traffic control centers and control ...

Flight history

Aeroflot Flight 7628

Aeroflot Flight 7628 was a twin

turbofan The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which ac ...

Tu-134 passenger jet, serial number 4352210 and registration CCCP-65816, that was built at the

Kharkiv Kharkiv ( uk, wikt:Харків, Ха́рків, ), also known as Kharkov (russian: Харькoв, ), is the second-largest List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Ukraine. At the time of the accident, the aircraft had accumulated 10,753 flight hours through 7075 cycles. There were 77 passengers and seven crew members on board the aircraft. Passengers included personnel of the Pakhtakor Football Club.

Air traffic control

En route to their destinations both aircraft passed through the

Kharkiv Kharkiv ( uk, wikt:Харків, Ха́рків, ), also known as Kharkov (russian: Харькoв, ), is the second-largest List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Ukraine.air traffic control Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled airs ...

(ATC) center airspace. This area was characterized by high traffic density and air traffic controllers often had to carry more than a dozen aircraft simultaneously. This problem had been discussed since the early 1970s, but by the end of the decade the problem had not been solved. The southwest sector, covering from 180° to 255° was especially complex and unpredictable. On 11 August 1979, at 07:50 MSK a new shift of air traffic controllers began work, headed by Sergei Sergeev. In the difficult southwest sector he employed an inexperienced 3rd-class controller, 20-year-old Nikolai Zhukovsky, under the supervision of 1st-class controller, 28-year-old Vladimir Alexandrovich Sumy. Adding to the situation that day was that

Leonid Brezhnev Leonid Ilyich Brezhnev; uk, links= no, Леонід Ілліч Брежнєв, . (19 December 1906– 10 November 1982) was a Soviet Union, Soviet politician who served as General Secretary of the Communist Party of the Soviet Union, Gener ...

was embarking on a trip to

Crimea Crimea, crh, Къырым, Qırım, grc, Κιμμερία / Ταυρική, translit=Kimmería / Taurikḗ ( ) is a peninsula in Ukraine, on the northern coast of the Black Sea, that has been occupied by Russia since 2014. It has a pop ...

. Authorities wanted to give the Soviet leader a clear flight path and this caused considerable disruption of the airline flight operations in the area.

Accident sequence

At 12:54, Flight 7628 took off from

Voronezh Voronezh ( rus, links=no, Воро́неж, p=vɐˈronʲɪʂ}) is a city and the administrative centre of Voronezh Oblast in southwestern Russia straddling the Voronezh River, located from where it flows into the Don River. The city sits on the ...

airport on the last leg of a domestic scheduled route from

Chelyabinsk Chelyabinsk ( rus, Челя́бинск, p=tɕɪˈlʲæbʲɪnsk, a=Ru-Chelyabinsk.ogg; ba, Силәбе, ''Siläbe'') is the administrative center and largest city of Chelyabinsk Oblast, Russia. It is the seventh-largest city in Russia, with a ...

to Voronezh, then to Kishinev. At 13:11, Flight 7880 departed

Donetsk Donetsk ( , ; uk, Донецьк, translit=Donets'k ; russian: Донецк ), formerly known as Aleksandrovka, Yuzivka (or Hughesovka), Stalin and Stalino (see also: Names of European cities in different languages (C–D), cities' alternat ...

airport bound for

Minsk Minsk ( be, Мінск ; russian: Минск) is the capital and the largest city of Belarus, located on the Svislach and the now subterranean Niamiha rivers. As the capital, Minsk has a special administrative status in Belarus and is the admi ...

. At 13:17:15, Flight 7628 contacted ATC to report it was at

flight level In aviation and aviation meteorology, a flight level (FL) is an aircraft's altitude at standard air pressure, expressed in hundreds of feet. The air pressure is computed assuming an International Standard Atmosphere pressure of 1013.25 hPa ...

(FL) and requested permission to climb to FL . Flight 7628 also informed ATC it would reach the Volchansk

waypoint A waypoint is an intermediate point or place on a route or line of travel, a stopping point or point at which course is changed, the first use of the term tracing to 1880. In modern terms, it most often refers to coordinates which specify one's posi ...

at 13:22 and the

Krasnohrad Krasnohrad or KrasnogradAlso known as ''Krasnograd'' fortress (Красноград) (1731-1784), ''Konstantinograd'' fortress (Константиноград) (1784-1922), city of Konstantinograd (1922-1943). ( uk, Красногра́д, ) is a ...

waypoint at 13:28, but controller Zhukovsky incorrectly recorded 13:19 to 13:26 respectively, which placed the aircraft ahead of schedule. At 13:21:43, Flight 7628 re-contacted the ATC center and again requested permission to climb up to 9600 meters, but Zhukovsky rejected that request. At 13:25:48, Flight 7880 bound for Minsk, informed ATC they had departed

14 minutes before and were at , and that they would reach the Dnipropetrovsk (now the city

Dnipro Dnipro, previously called Dnipropetrovsk from 1926 until May 2016, is Ukraine's fourth-largest city, with about one million inhabitants. It is located in the eastern part of Ukraine, southeast of the Ukrainian capital Kyiv on the Dnieper Rive ...

) waypoint at 13:34 and the

Kremenchuk Kremenchuk (; uk, Кременчу́к, Kremenchuk ) is an industrial city in central Ukraine which stands on the banks of the Dnipro River. The city serves as the administrative center of the Kremenchuk Raion (district) in Poltava Oblast (pr ...

waypoint at 13:44. Zhukovsky confirmed the location of the aircraft and ordered them to climb to and maintain . At 13:27:50, Flight 7628 contacted ATC and reported that they were over Krasnohrad at FL . Flight 7628 then asked controller Zhukovsky for their ground speed and the speed of another Tu-134A identified as 65132, flying at FL . Flight 7628 was flying at and aircraft 65132 was at . Because of the speed difference ATC refused to let flight 7628 climb to 9600 metres. Flight 7628 confirmed the instructions, although they tried to clarify that they could also slow down after the climb. This was the last radio transmission from Flight 7628. At 13:30:40, Flight 7880 contacted ATC and reported they were at , away from the Dnipropetrovsk beacon. The controller confirmed their position and instructed them to climb to an altitude of 8400 meters. After 3 minutes (13:34:52) Flight 7880 reported at an altitude of , at the Dnipropetrovsk beacon. Controller Zhukovsky initially incorrectly identified the aircraft on radar and, when he properly identified it, he realized that it was on a collision course with another aircraft (CCCP-86676 – an

Ilyushin Il-62 The Ilyushin Il-62 (russian: Илью́шин Ил-62; NATO reporting name: Classic) is a Soviet long-range narrow-body jetliner conceived in 1960 by Ilyushin. As successor to the popular turboprop Il-18 and with capacity for almost 200 pa ...

at 9000 meters.) and therefore instructed Flight 7880 to stay at 8400 meters, which was confirmed. Flight 7628 was flying on

Airway The respiratory tract is the subdivision of the respiratory system involved with the process of respiration in mammals. The respiratory tract is lined with respiratory epithelium as respiratory mucosa. Air is breathed in through the nose to th ...

50 (Magdalinovka – Ball, course 201°) and Flight 7880 was on Airway 147 corridor (Dnipropetrovsk – Kremenchuk, course 300°). These corridors intersect at an angle of 99° north-east of Dniprodzerzhynsk. Because of previous errors, the controller's perception of the location of each aircraft was incorrect. When Zhukovsky's supervisor Sumy overheard the radio traffic and saw the aircraft converging on the radar screen he realized the catastrophic situation and attempted to correct it. At 13:34:07 controller Sumy ordered aircraft 86676 (IL-62) from . At 13:34:21 Sumy repeated the order then directed Flight 7880 from 8400 meters to the now vacant altitude at . *13:34:07 ATC to aircraft 86676 ''"Take 9600."'' *13:34:21 ATC to aircraft 86676 ''"Take 9600."'' *13:34:23 ATC to Flight 7880 ''"and you take a 9. Over 8400 Dneprodzerzhinsk crossover."'' *13:34:25 aircraft 86676 to ATC ''"9600."'' *13:34:33 (inaudible.) ''"Got it ... 8400"'' The controller heard a muffled reply and assumed it was an acknowledgement from Flight 7880, but the muffled transmission was actually from aircraft 86676 and Flight 7880 remained at 8400 meters.

Collision

Flight 7628 had strayed to the left of the airway by approximately , while Flight 7880 was to the left by . At 13:35:38 both aircraft suddenly disappeared from ATC radar screens. Zhukovsky tried to contact them, but they did not respond. At 13:37, Igor Chernov, the captain of an

Antonov An-2 The Antonov An-2 ("kukuruznik"—corn crop duster; USAF/DoD reporting name Type 22, NATO reporting name Colt) is a Soviet mass-produced single-engine biplane utility/agricultural aircraft designed and manufactured by the Antonov Design Bure ...

(CCCP-91734) flying from

Cherkasy Cherkasy ( uk, Черка́си, ) is a city in central Ukraine. Cherkasy is the Capital city, capital of Cherkasy Oblast (Oblast, province), as well as the administrative center of Cherkasky Raion (Raion, district) within the oblast. The c ...

to Donetsk, reported "Something falls from the sky!". At 13:40 Chernov reported seeing aircraft parts in the area of Dniprodzerzhynsk (current

). Both aircraft collided in a cloud at an altitude of , approximately over Dniprodzerzhynsk. Flight 7880's right wing sliced through Flight 7628's forward

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

, tearing off part of 7880's right wing, the debris of which was ingested by 7880's right engine. The impact spun 7628 to the right, causing the tails of both aircraft to collide at which time the left engine of 7628 struck the keel of 7880, and 7628's right wing was torn off. Flight 7628 tumbled out of control and broke up, with debris scattered over an area measuring . Damage to 7880 included the loss of most of the

empennage The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third ed ...

, one of the engines and a section of the right wing. The pilots of 7880 attempted an emergency landing, but at an altitude of approximately they lost control and at 13:38 crashed to the ground north-east of Dniprodzerzhynsk, completely destroying the aircraft.

Investigation

In the subsequent investigation the commission concluded that

center of gravity In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weight function, weighted relative position (vector), position of the distributed mass sums to zero. Thi ...

and takeoff weights of both aircraft were within the normal range and that there was no explosion or fire prior to the collision. The commission also found that maintenance was carried out in accordance with the requirements of the regulations and that the level of training of flight crews of both aircraft, as well as their work experience, were not the cause of the crash. When the commission examined the action of the controllers they discovered a series of errors made by Zhukovsky: * Refused Flight 7628's request to climb from to , stating it was in dangerous proximity to aircraft 65132. The interval was – close to the minimum, although the safety distance between 65132 and Flight 7628 could have been increased by reducing the ground speed of the latter. * Directed Flight 7880 to climb from 7200 meters to 8400 meters, although the crew did not request this. As a result, there was a conflict situation with Flight 7628. * Did not allow aircraft 86676 to climb to This would have increased the safety distance between it and aircraft 65132. * Allowed crews to violate radio rules and argue with the manager about the instructions received. Two minutes and 51 seconds before the collision, Zhukovsky began a 47-second argument with the crew of a Ukrainian

Yakovlev Yak-40 The Yakovlev Yak-40 (russian: Яковлев Як-40; NATO reporting name: Codling) is a regional jet designed by Yakovlev. The trijet's maiden flight was in 1966, and it was in production from 1967 to 1981. Introduced in September 1968, the Ya ...

identified as aircraft 87327, explaining the need for them to go to another altitude. The investigators also discovered that the more experienced controller, Vladimir Sumy, was in error during the last minutes before the crash, having received a vague answer without a call sign, he did not confirm if the crew of Flight 7880 understood. Sumy had previously received penalties for violations, including improper communication and phraseology. The senior controller, Sergei Sergeev, was found to have complicated the air traffic control environment by changing the responsibilities assigned to personnel, including assigning Sumy to supervise Zhukovsky. Nine months after the disaster, a court sentenced controllers Zhukovsky and Sumy to 15 years imprisonment in a

penal colony A penal colony or exile colony is a settlement used to exile prisoners and separate them from the general population by placing them in a remote location, often an island or distant colonial territory. Although the term can be used to refer to ...

. Sumy served 6.5 years, then was released for good behavior. , he lived in

Kharkiv Kharkiv ( uk, wikt:Харків, Ха́рків, ), also known as Kharkov (russian: Харькoв, ), is the second-largest List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Ukraine. The final conclusion made by the commission was that " e cause of the disaster were the mistakes and violations of the NPP GA-78 made by manager of the southwestern sector and dispatcher instructor regarding destination tier and providing the established intervals between aircraft compliance phraseology".

References

{{DEFAULTSORT:Dniprodzerzhynsk mid-air collision Accidents and incidents involving the Tupolev Tu-134 Aviation accidents and incidents in Ukraine Aviation accidents and incidents in the Soviet Union Aviation accidents and incidents in 1979 1979 in the Soviet Union Mid-air collisions Mid-air collisions involving airliners Aviation accidents and incidents caused by air traffic controller error

Aviation accidents and incidents involving professional sports teams Kamianske Pakhtakor Tashkent FK August 1979 events in Europe 1979 in Ukraine 1979 disasters in Ukraine