Warning system was off

Swiss admit collision alert device was not in operation

Switzerland’s air traffic control company yesterday admitted its automatic collision warning system was turned off for maintenance on Monday when a Boeing 757 and a Russian Tupolev 154 slammed into one another and exploded in a fireball above Lake Constance.

The revelation raised fresh concerns about the role of controllers from Skyguide, the private company that provides Swiss air traffic control, in the moments before the accident.

Russian officials have claimed ground staff in Zurich did not react fast enough to prevent the DHL cargo carrier and the Bashkirian Airlines passenger jet crashing at more than 35,000ft with the loss of 71 lives.

Five hundred rescue workers and investigators searched yesterday to gather debris, baggage and body parts scattered across the countryside by the force of the impact. The remains of the planes were transported to a disused hangar in Friedrichshafen where aviation experts started to reconstruct them.

Locals gathered to watch the salvage operation, as a lone hearse with red velvet curtains made repeated journeys up a winding road towards a large section of fuselage next to an apple plantation. The bodies of passengers, still strapped inside, were removed after the army brought in industrial saws to cut through the wreckage.

The families of the victims are due to arrive in the town of Friedrichshafen this morning.

The interior minister of the German state of Baden-Württemberg, Thomas Schauble, would not confirm reports that German criminal investigators had travelled to Zurich to question Skyguide officials.

The sole air traffic controller on duty at the time of the accident, who told the Russian pilot to dive a mere 50 seconds before the impact, was reportedly too traumatised to talk to investigators yesterday.

In Zurich, Roger Gaberelle, a Skyguide official, confirmed that “the [automatic collision warning] system was not working at the time”.

However, he denied that the two controllers on duty that night – one of whom was on a break at the time of the incident – acted irresponsibly.

The company insisted one air traffic controller was adequate to supervise five planes crossing Swiss airspace at that time and denied that their behaviour breached regulations. Maintenance staff had turned off the short-term collision alert (STCA) system for routine work.

“It is not against regulation to take a break at night when the traffic is light, regardless of whether the STCA system is off and the other controller is in agreement,” another Skyguide official, Philipp Seiler, said.

Earlier, a third company official had said the regulations had been broken.

Compounding problems for the Swiss, details emerged yesterday of a report which described Skyguide’s radar system as falling below European safety standards. The study, by the Swiss aircraft accident investigation bureau, was based on three near-misses between 1998 and 2000. It said that discrepancies of several seconds were possible between Swiss radar readings and those of neighbouring countries. Such timings could put the location of a plane on the radar screens out by up to 500 metres (1,600 feet).

But Skyguide, which became a limited company owned by the Swiss government in 1998, attempted again to shift blame on to the Russian Tupolev 154, claiming the plane did not have a working traffic collision avoidance system (TCAS) as required by international law.

“Accident investigators need to look into why it took three warnings before the pilot of the Tupolev responded and why the Tupolev’s [collision avoidance system] wasn’t responding,” said Mr Seiler.

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