The head of UK air traffic control body Nats apologised to MPs for the system meltdown on August bank holiday Monday last week but rejected accusations of serial failings.
A one-off hearing by the Transport Select Committee of MPs shed light on the cause of the disruption on August 28. MPs heard the issue arose at 8:30am when Nats’ system received “an incredibly unusual flight plan” of an aircraft flying from the US to Paris. Both the system and back-up system shut down.
Airline chiefs reported being informed just after 11:00. Nats chief executive Martin Rolfe reported: “The system was back up at 2:30pm and everything running by 5pm.”
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Loganair chief executive Jonathan Hinkle suggested the problem was a flight plan with duplicate ‘way points’, saying: “It seems very basic. I can’t understand why it took so long to fix.”
Ryanair chief Michael O’Leary claimed: “Nats will explain this was a once-in-a-lifetime event, but all other ATC systems simply reject a duplicate flight plan. Nats crashed its system and its back-up system and had its engineers working from home.” He dismissed Nats’ initial account of the events as “a tissue of nonsense, a tissue of lies”.
Rolfe told MPs: “We need to know where every aircraft is flying from and to and the way points in between.” But he said the problem with the unusual flight plan was not just duplicate way points, arguing: “It was sufficiently different that the system stopped.”
The flight plan had come from European air navigation body Eurocontrol and Rolfe said: “The combination of sequencing and the translation via Eurocontrol’s system to ours [meant] the system didn’t recognise it. [But] it didn’t say ‘It’s because of this flight plan.’”
Rolfe explained: “We handle duplicate flight plans all the time. On four occasions in the last five years the back-up system has taken over.” This time the back-up “came up with the same response”.
He said: “We resolved the issue as quickly as we could in circumstances where we didn’t know precisely what the problem was.
“The system didn’t collapse. It shut down. Other providers around Europe have suffered similar incidents. France had a similar problem that put its system out for seven to eight hours. Italy had a problem the same day. These things are not uncommon but normally fixed within minutes.”
Rolfe rejected O’Leary’s allegations, saying: “Safety is at our core. We don’t treat bank holidays as different. We have the right number of engineers on site. Others can dial in to assist.”
He said Nats’ initial report on the incident was based on Eurocontrol data, noting: “We weren’t trying to determine the impact. The CAA will do that.”
Rolfe added: “I understand the frustration of airlines. [But] Nats’ priority is safety. It was set up by the government and airlines that way.”
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