Legal inquiry launched against Swiss air controller

Skyguide staff will not be allowed to man the controls on their own Keystone

The Swiss controller on duty when two planes crashed over Lake Constance is now the focus of an investigation by German prosecutors.

The Konstanz prosecutor’s office has begun its inquiry into the actions of the controller on the fateful night of the crash. The man is suspected of negligent behaviour, a charge that is also levelled against high-ranking Skyguide officials, according to the Stuttgarter Nachrichten.

The controller has been questioned on a number of occasions by the Swiss authorities in recent days, who have already begun their own legal proceedings. The German prosecutors decided to launch their own investigation after learning of the outcome of these meetings.

The Russians have also made a request for judicial cooperation with the German prosecutors, wishing to be associated with all the proceedings.

German investigators said on Friday that the cockpits recorders revealed that both the Swiss air traffic controller and the pilots of the doomed aircraft were aware in final seconds that a collision was imminent.

The two planes crashed into each other at 11,500 metres above Lake Constance on the night of July 1, killing all 71 people on board, most of whom were Russian schoolchildren.

Investigators said that shortly after the controller twice instructed a Tupolev Tu-154 passenger plane to descend to avoid a collision with a Boeing cargo jet, the pilot of the cargo jet told the controller his Boeing was also heading lower.

“The crew of the Boeing reported to the controller that they were descending in accordance with a command from the TCAS [on-board warning] system,” said the German BFU air accident investigation agency.

He added that the report had been made 13 seconds before the collision.

Contradictory instructions

Investigators revealed earlier this month that the Swiss controller had ordered the Tupolev jet to descend, contradicting a warning from that plane’s computer.

On Friday, they said it was now clear that the Russian crew did not point out to the Swiss controller that their TCAS system was ordering them to climb, when he ordered them to lose altitude.

In the final seconds before the collision, the TCAS systems on both planes warned their pilots to take evasive action. The Boeing pilots were told to lose altitude more quickly 22 seconds before the collision, while the Russian pilots received an instruction to climb sharply eight seconds before impact.

swissinfo with agencies