Representatives of the Swiss air traffic control service, Skyguide, have claimed that their controller "acted correctly" to try and divert the Tu-154 and Boeing 757 flying at the same height. Skyguide representatives reiterated their claim at a Zuerich press-conference that the Tu-154 pilot only began to lose altitude after being told for the third time by the controller.
This command was obeyed. The questions why the Boeing cargo plane was allowed to fly on at the same altitude and why the planes were allowed to become so close remained unanswered.
The representatives said that Skyguide was in contact with the Swiss Federal Bureau of Air Crashes to establish why the Tupolev and the Boeing collided.
According to them, Skyguide will attempt to solve the unanswered questions during the investigation into the tragedy. The first task will concentrate on the late reaction of the Tu-154 crew to the order to change altitude, while the second will focus on why the Boeing's warning system did not provide a flight trajectory that would have allowed a collision to be avoided.
Earlier First Deputy Transport Minister of Russia and the Head of the state Civil Aviation Service Alexander Neradko had announced that a mistake by the Russian crew had been the cause of the tragedy.
Neradko let it be understood that the accident could have happened as a result of a mistake in the part of ground services. According to him, the human factor influenced the majority of accidents and occasionally was connected with the ground.
In his opinion, the services in control of flights could have made the mistake. He said that the planes' flight-paths crossed each other at a right angle.