On the afternoon of August 11, 1979, two Tu-134A passenger airliners collided in dense clouds near the Ukrainian city of Dneprodzerzhinsk through the fault of dispatchers, killing 178 people, including the football players of the Tashkent team “Pakhtakor”.
Seemingly. the conclusions made during the investigation of the causes of this disaster should have excluded the repetition of such tragedies in the future. However, less than six years later, an almost "mirror" emergency happened in the sky over Lviv …
Difficult weather conditions
When on May 3, 1985 at 10.38 a passenger plane Tu-134A of the Estonian Civil Aviation Administration, en route to Lviv - Chisinau, soared up from the concrete tarmac of the Tallinn airfield, clear, warm weather remained over the entire Baltic region. But as we moved south, the situation on the track became more difficult. Soon the plane flew in the thick of multi-layered rain clouds, periodically falling into turbulence zones, passing literally along the edge of thunderstorm fronts, where beams of lightning flashed.
However, the crew commander N. I. Dmitriev did not see anything unusual in the situation overboard. To him, a pilot of the 1st class, Hero of Socialist Labor, who had flown more than one thousand hours on this type of aircraft, such weather conditions were not unusual. The captain's calm confidence was passed on to the crew, which also consisted of experienced aviators.
The 73 passengers in the cabin, of course, were nervous when the airliner got into a turbulence, but they still trusted the qualifications of their "air cabbies", as well as the reliability of the car itself, carrying them at a speed of 850 km / h. Unfortunately, in aviation, not everything depends on the serviceability of the liner and the experience of its crew. Often, ground services act as arbiters of destinies. At 12.06, following at an altitude of 7800 m, the Tu-134A entered the Lviv air zone. The crew asked the dispatcher of the eastern sector of the RC (regional center) for permission to occupy the 4200 m level. It was clear to everyone that they would have to land in conditions of practically zero visibility.
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Clouds over Lviv
Just four minutes before this request, an An-26 military transport aircraft took off from the Lviv airport, nicknamed by the pilots for the characteristic sound of the working engines "The Ugly Duckling". He was heading for the Chkalovsky airfield near Moscow, and his tanks were completely filled with fuel. Among the passengers were practically the entire leadership of the Air Force of the Carpathian Military District, including the commander - Major General of Aviation E. I. Krapivina. Both sons of the commander volunteered to fly with their father. The wife of the commander of the 40th Army Boris Gromov was also in the cabin. The aircraft crew was considered one of the best in the area. The commander of the ship, Lieutenant Colonel Shishkovsky, flew a total of about 6 thousand hours.
Other members of the crew also enjoyed a reputation for being tough professionals. The second pilot's seat, by the way, was occupied by Lieutenant V. Bykovsky, the son of the famous cosmonaut Valery Bykovsky. True, the young officer flew on the An-26 for only 450 hours, but he proved himself to be the best.
By the time of takeoff, the weather in the Lviv region had completely deteriorated. The sky over the airfield was covered with almost continuous rain clouds. At the same time, the lower edge of the clouds literally hung above the ground, and the upper boundary of heavy, ragged clouds reached 5-6 kilometers in height. There was virtually no visibility in this gigantic layer of "jelly". And this meant that a significant share of the responsibility for flight safety fell on the shoulders of the dispatchers.
Dispatching service
On this day, the flight control shift was headed by L. Kvashin, an experienced flight manager at the Lviv airport. He graduated from the Civil Aviation Academy and was qualified as a 1st class air traffic controller. The dispatcher of the eastern sector of the RC was no less experienced employee V. Shevchenko, and the dispatcher of the approach was P. Savchuk.
In the past, Savchuk himself flew a lot of hours, and after being written off by age from the flight service, he graduated from a special two-month course and was admitted to independent work with the qualification “traffic dispatcher of the 3rd class”.
These specialists had high-quality equipment at their disposal: the TRL-139 survey track blocker, the root-AS secondary locator, and the aerodrome survey locator. With the help of this technique, it was possible to control the movement of aircraft in any weather conditions. Generally, military and civil aircraft fly according to slightly different rules. For civil aircraft, so-called air corridors have been established, which are clearly marked and unchanged. In the rest of the space, military aircraft fly, which, in turn, are not allowed to enter the corridors. Still, there are times when a military aircraft uses a civilian corridor. And then a lot, if not everything, depends on the qualifications of the dispatcher who "guides" the plane.
Third plane
As in the case of the tragedy near Dneprodzerzhinsk, there was also a third plane. A few minutes before the start of the military An-26, the passenger An-24 departed from Lviv in the same direction. It was in these "three pines" that the former good pilot, but insufficiently trained as a dispatcher P. Savchuk, got lost. However, at first, nothing foreshadowed trouble.
When the Tu-134A asked for permission to take a lower echelon, the Shevchenko dispatcher first gave the go-ahead, but after checking the radar readings, changed his command. The same passenger An-24 flew towards the "carcass" at an altitude of 4500 m, so the commander of the Estonian airliner was ordered to descend to the echelon of 4800 m.
After both aircraft had safely dispersed in thick clouds, N. Dmitriev received permission to descend to 4200 m. Meanwhile, the military An-26, also flying on a collision course, climbed to an altitude of 3900 m. He received permission to occupy this echelon from Savchuk. At the same time, information about the movement of the oncoming side was transmitted to the radio operator of each of the two aircraft.
The plane An-26 continued to "lead" Savchuk. According to his calculations, the distance of the car from the drive station was at least 65 km. But the trouble is that he confused the illumination of the aircraft on the all-round view indicator, mistaking the An-24 flying in the same direction for "his" An-26. According to Savchuk's data, the Tu and An-26 should have dispersed in space at a considerable distance from each other, but the error was about 10 km!
An experienced dispatcher would certainly have checked everything again, despite the fact that there were a couple of minutes left for this, but Savchuk hurried to transfer the military plane to the dispatcher of the eastern sector of the Shevchenko RC. And he himself gave the command to the crew of the "carcass" to descend to 3600 m. As for his more experienced superiors, they did not control the actions of their subordinate, who did not yet have confident skills in working with radar equipment.
Seven seconds
At 12.13, two planes collided at the “fatal” altitude of 3900 m, near the town of Zolochev. The decoding of the “black boxes” showed later that for a fraction of a second before the impact, both pilots noticed each other in the burst of clouds and tried to take the fast cars aside. But it was too late, not even a steep bank saved. The planes, however, collided not head-on, but left-handed. From a terrible blow, the wing of the An-26 was torn off, and it, having lost the ability to stay in the air, fell to the ground for seven seconds, while still living people were screaming inside.
Tu-134A collapsed in the air. Presumably, all of its passengers died instantly. The wreckage of aircraft fell 15 km from Zolochev, on a cultivated field. Despite the rain, some fragments continued to burn. Especially hot flames devoured a military aircraft, whose tanks were fully fueled before a long-distance flight. From the fierce scorching heat, the black soil around turned into a real swamp, in which the arrived rescuers literally got stuck. Alas, there was no one to save. In total, 94 people died in this disaster.
Some experts said that the holidays were an indirect fault of the tragedy. The dispatchers allegedly did not check the locator readings because they were in a hurry for lunch. In contrast to the situation near Dneprodzerzhinsk, where a whole round dance of liners circled in the air, here the sky was much freer. The commission thoroughly studied the circumstances of this tragedy. Its main conclusion repeated only what was clear to specialists in advance. The disaster was not supposed to happen despite the bad weather. But again, for the umpteenth time, the notorious "human factor" let down.