The Civil Aviation Authority has promised a review of last month’s air traffic control meltdown as well as how it was handled by NATS, which manages UK airspace, after it confirmed it was not a cyber attack.
More than 200,000 passengers were left stranded when ATC went down on the late August Bank Holiday Monday, with some only managing to get home in the last few days.
An interim report by NATS has since revealed that the shutdown to both the main ATC computer and its backup computer occurred after a single flight plan presented information that it had never seen before.
This meant that air traffic controllers had to input data manually, but they were only able to process 60 flights an hour compared to 400 when the automated system is operating.
NATS Chief Executive Martin Rolfe said a cyber attack had been ruled out after investigations revealed that the shutdown was caused when a flight plan was presented without a valid UK exit point. The system searched for the nearest given waypoint beyond the UK but it picked up one with the same three letter code that was thousands of miles away, which meant it couldn’t enter a valid route.
“We’ve had 15 million flight plans pass through the system and we can be absolutely certain that we’ve never seen this set of circumstances before,” Rolfe said. “It was a one in 15 million chance,” he added.
The interim report has been passed to the CAA and to Transport Secretary Mark Harper while NATS continues investigating.
The CAA said today that it would carry out a full independent review of the events.
CAA Joint Interim Chief Executive Rob Bishton said: “Millions of passengers every year rely on air traffic control to work smoothly and safely. The initial report by NATS raises several important questions and as the regulator we want to make sure these are answered for passengers and industry.”