European flight system outage not down to external interference

BERLIN, April 4 (Reuters) - A computer failure that resulted in thousands of flight delays across Europe on Tuesday was not caused by outside interference, the network manager said.

Eurocontrol, which is responsible for the flow of traffic across Europe's skies, is carrying out an investigation into the outage of the ETFMS flight planning processing system that affected passengers across the region.

The failure of the ETFMS on Tuesday morning meant flight plans were lost and departures had to be restricted from airports across the region. The system was back up and running by 1800 GMT on Tuesday.

"The trigger event was an incorrect link between the testing of a new software release and the live operations system," Eurocontrol said on Wednesday. "We are confident that there was no outside interference."

It said measures had been put in place to ensure it would not happen again.

The ETFMS system, which manages up to 36,000 flights a day, has only ever failed once before, in 2001, Eurocontrol said.

Eurocontrol had estimated that around half of Tuesday's 29,500 flights would be affected but said on Wednesday it could not yet provide exact figures on the impact. (Reporting by Victoria Bryan Editing by Maria Sheahan)