Investigation continues into cause of mid-air crash

Rescue workers are still searching among the wreckage of both planes Keystone

Experts are continuing their search for clues to the mid-air collision of two jets close to the Swiss-German border on Monday night which killed 71 people.

On Wednesday morning, investigators combing the crash site – spread over some 30 kilometres near Lake Constance – said they had recovered the black box flight recorder from the Boeing 757 freight jet.

A flight-data recorder from the other jet, a Tupolev 154 charter aircraft with 52 children on board, was found on Tuesday.

Hundreds of recovery workers resumed efforts at daybreak on Wednesday to sift through the wreckage and have so far found 28 bodies, some of which were still strapped into seats of the Russian plane.

The mid-air collision occurred late on Monday night in Swiss-controlled airspace at a height of over 11,000 metres when both planes dived to avoid each other.

A German police spokesman said the Boeing’s black box would be taken away for analysis, while investigators continued the search for the aircraft’s voice recorder.

The German transport minister, Kurt Bodewig, said the flight data recorders from both aircraft would be examined by authorities on Wednesday.

Apportioning blame

But even before the black boxes had been located and sent for analysis, questions were being asked about the role of Swiss air traffic controllers in the minutes leading up to the mid-air crash.

Skyguide – the Swiss air traffic control service responsible for monitoring the two aircraft at the time of the impact has admitted that an anti-collision alarm system used by air traffic controllers was being repaired and therefore out of service on Monday night.

But Patrick Herr, a spokesman for Skyguide, said the question of whether the accident could have been prevented if the system – which sounds an alarm when two aircraft are approaching each other – had been in operation was “purely hypothetical”.

According to Skyguide, five planes were in the air when the two aircraft crashed. Only one air traffic controller was on duty at the time because his colleague was away on a break.

After initial reports suggested the first warning had been issued 90 seconds before the crash, Skyguide later revised this figure, admitting the air traffic controller in charge had given the first instruction to descend just 50 seconds before the crash.

By the time the Russian plane began to descend, the Boeing 757 – operated by the freight company, DHL – was also diving, apparently instructed to do so by its on-board collision avoidance system.

But Bashkirian Airlines – the company which operated the TU-154 jet – denied its crew had failed to react to warnings issued by air traffic control authorities.

“It is the opinion of our company,” said airline director, Nikolai Odegov, “that the air traffic control was at fault.”

Instruction to dive

Skyguide insists the Russian pilot had been given ample warning to react, but a German pilot representative said the instruction to dive should have been received earlier.

“Of course, we must ask why the two planes were not brought apart earlier,” said pilots’ union spokesman, George Fongern.

“That would have been the usual thing to do,” he added.

Skyguide spokesman, Urs Ryf, said the warning had been “tight but sufficient”.

“The controllers gave several instructions and it’s up to the investigations to reveal everything else,” he said.

Sepp Moser, a Swiss aviation analyst, said the delayed warning “may have been one of the contributing factors” which led to the fatal collision.

“Accidents always have many contributing factors…but I don’t know, for instance, how many other aircraft this air traffic controller had to care for at the same time,” he told swissinfo.

Russian investigators sent by President Vladimir Putin arrived on Tuesday evening to join the recovery efforts, while the United States National Transportation Safety Board said it was sending five investigators at the request of German authorities.

In Washington, a White House spokesman said President George W Bush was sending condolences “on behalf of the United States to all the families of the victims of this tragic air accident and also to the people of Russia for their loss”.

Officials are currently working to fly in relatives of the 52 Russian children who died in the crash.

swissinfo with agencies