Investigation of the catastrophe: Several seconds before the collision of TU-154 and Boeing-757

It was reported already, that crews of TU-154 and Boeing-757 flying over Boden Lake July 2 received different signals: alternative commands for manoeuvre and notification about possible collision, from their own automatic systems and from the Swiss flying control officer tracking the flights. Today, this was confirmed by German Office of Air Accidents in Braunschweig which occupies itself with official investigation of the catastrophe reasons.

According to RIA ‘Novosti’, the Office presented the record of what had happened several seconds before the catastrophe.

23:34:42 (Middle-European Time): Automatic notification systems signals about dangerous movement in the sector of the flight.

7 seconds later: Flying control officer of Skyguide gives to TU-154 a command to go down at a height of 35 thousand foots (echelon 350). The Officer receives confirmation about it from the Russian crew.

7 more seconds later: The Boeing crew receives a recommendation from its automatic system to go down, while TU-154 receives from its automatic system a recommendation to climb. The Boeing follows the command immediately, while Tu-154 keeps for some time the same flying path (echelon 360).

7 more seconds later: Flying control officer repeats the command to the Russian liner to go down fast, i.e. to pass on to a height of 35 thousand foots. The TU-154 confirms this command and starts to go down. Just after it flying control officer reports that in echelon 360 there is one more aircraft.

7 more seconds later: Boeing receives from its automatic system an instruction to accelerate going down.

9 more seconds later: Boeing reports to flying control officer that is goes down following the command of its automatic system. 5 more seconds later: Tu-154 crew receives from its automatic system a command to accelerate the climb.

In 8 seconds the collision takes place.


Translated by Vera Solovieva

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