Swiss prosecutors open probe of air controllers

ZURICH, July 4 - Zurich prosecutors have launched a criminal investigation into whether negligence by Swiss air traffic controllers may have been responsible for Monday's mid-air crash that killed 71 people, they said on Thursday.

At issue in the probe for manslaughter and negligent disruption of public transport is whether Skyguide controllers acted correctly in the moments leading up to the crash of a Russian airliner and a DHL cargo jet.

"The subject of the probe...is carefully investigating the exact chain of events during the time Skyguide was tracking these two aircraft from Zurich airport, and clarifying open questions on whether Skyguide staff made errors for which they could be held criminally liable," Buehlach district attorney Christoph Naef said in a statement.

Buehlach is the district that includes Zurich's airport, where Skyguide monitors were tracking the doomed flights.

Skyguide has given at times conflicting accounts of its role in the disaster but insisted its staff did nothing wrong.

Officials have said controllers instructed the Russian jet to lose altitude and thus avoid a crash 50 seconds before impact, but the Russian pilot was slow to respond.

They acknowledged the 50-second warning was cutting it close but stressed it was still within acceptable limits.

Both jets were diving in a vain attempt to steer clear when they flew into each other and exploded in a ball of flame.

Skyguide officials had no comment on a Russian news agency report quoting unidentified investigators at the crash site near Lake Constance as saying the Russian crew had warned controllers the jets were on a collision course 90 seconds before the crash.

RADAR SAID TO BE IN ORDER

Swiss air traffic controllers insisted their radar was working perfectly well at the time of the crash and that recommended upgrades would not have prevented the disaster.

A report last week by Swiss aviation safety officials found the radar did not fully meet standards laid down by Eurocontrol, the European agency in charge of tracking aircraft in flight.

But a spokesman for Skyguide, which also monitors airspace over parts of southern Germany, said the proposed changes played no role in the crash.

"There is no link at all here,"spokesman Felix Hitz said. "We were always completely functional even though we were in a degraded mode at the time. We were in fallback radar mode, but this is completely OK."

Skyguide said on Wednesday a system that warns controllers that aircraft are on a collision course had been switched off for maintenance at the time of the crash, which occurred just across the Swiss border in the southern tip of Germany. The partner to the controller on duty was taking a break at the time.

One of the report's recommendations was that controllers' screens should update the location of aircraft every eight seconds rather than every 12, as is now the case in Switzerland.

But Hitz said such a change was not crucial. He said Skyguide already had implemented many of the recommendations from the Federal Bureau for Air Accident Investigations.

"We have long-term programmes that optimise the system. This is completely under control," he said.

As it happened, Skyguide renewed its insurance coverage the very day of the tragedy. A spokesman said the renewal was a simple rollover of an existing insurance policy, but said he could not give any more details.