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London airspace severely restricted after control centre computer failure London airspace severely restricted after control centre computer failure
(about 1 hour later)
London airspace has been severely restricted after a system failure at the main national control centre in Swanwick. Passengers experienced hours of delays and cancelled flights after a system failure at the main national air traffic control centre in Swanwick on Friday afternoon.
Planes started to depart again after 4.15pm on Friday after more than an hour of airspace restriction, but passengers travelling to and from London’s largest airports faced lengthy delays and cancellations. Heathrow has cancelled 50 flights and expects the number to rise. Planes were grounded as London airspace was severely restricted for about an hour, closing runways at Heathrow, Europe’s busiest airport, for a period.
Air traffic controller Nats said it was still investigating the cause of the failure but had now resolved the problem and that flight operations were being restored to normal. Flights which did land at London’s airports were unable to unload passengers with gates gridlocked. Others were taking off up to four hours late.
However, the restriction, which appears to have been triggered by a computer problem rather than a power outage, as had earlier been thought possible, is likely to divert and disrupt hundreds of international flights after hours of delays, with aviation experts warning that the knock-on effects would be felt far beyond London. Flights started to depart again after 4.15pm, but passengers travelling to and from London’s largest airports faced lengthy delays and cancellations. Heathrow had cancelled 50 flights by the early evening and expected the number to rise.
A spokeswoman for Nats confirmed there was a technical failure at Swanwick, Hampshire, the leading control centre for southern UK airspace. Among the passengers waiting for information on outgoing flights at Heathrow was Claire Baron, a young South African, who needed to get to Zurich on Friday night in order to catch a long haul connection to Johannesburg.
She said earlier: “We are in the process of getting the incident response mobilised. We don’t know what the cause is, but there is a technical failure. “When you get to the front (of the queue) they’re saying that it takes 10 minutes to process and all they will do is give you a letter and a phone number,” she said, referring to long queues at Swiss Airlines. “‘They’re doing the best they can but I’m being fobbed off, [they’re] saying go home or get a hotel.”
“We’re sorry if it causes any delays today. Our priority is to understand what has gone wrong and to get things working as quickly as possible.” Two Argentinian teenagers trying to get to Zurich for a connecting transatlantic flight had better luck. “We’re good at arguing. It’s in our culture,” said one, who added they had been rebooked on an early Saturday morning flight after lobbying officials and telling themthey did not want to queue for two hours. “I said that there was a special circumstance. My dog had to be put down today so I was in a really bad mood anyway.”
Brussels-based Eurocontrol had earlier alerted airlines that traffic would not move until 7pm this evening. A message on the site said: “There has been a failure of the flight data computer server at London Area Control Centre (LACC). Engineers are working on the problem and more information will be given when available. No traffic has been accepted until 1900.” Air traffic controller Nats was able to restore its computer services after the unknown glitch but hundreds of international flights had already been diverted or disrupted.
Departures at London airports were at a standstill by mid-afternoon. A statement from Heathrow airport said: “There is a technical problem at the Nats control centre in Swanwick, which is affecting UK airspace. Flights are currently experiencing delays and we will update passengers as soon as we have more information.” Transport secretary Patrick McLoughlin said: “Disruption on this scale is simply unacceptable and I have asked Nats for a full explanation of this evening’s incident.”
Gatwick said some incoming flights were still landing and that there had been limited departures on certain routes. A spokeswoman for Nats confirmed there was a technical failure at Swanwick, in Hampshire, the leading control centre for southern UK airspace.
Aircraft were being kept on the asphalt at Luton and Stansted. Manchester has said it was not affected, but other regional airports said departures were potentially disrupted. She said: “The system has been restored. However, it will take time for operations across the UK to fully recover so passengers should contact their airline for the status of their flight.
A similar computer glitch affected operations at Swanwick for almost 12 hours last December, leaving thousands of passengers stranded as hundreds of flights were grounded. Experts said that a failure in some of the new upgraded software may have introduced a glitch. “We apologise for any delays and the inconvenience this may have caused. We are investigating the cause of this fault but can confirm that ,contrary to some reports, it was not due to a power outage.”
Doug Maclean, a consultant at DKM aviation, said: “The way the airspace is sectorised is designed to cope with this, so that if you have a glitch in one operations room, the whole of the UK is not affected. It sounds very much that it was the upper airspace sector which was affected, which means the contingency is that the London terminal area which handles the lower airspace would have taken over some of the flights.” Experts said that a failure in some of the new upgraded software may have introduced a glitch. Doug Maclean, a consultant at DKM aviation, said: “The way the airspace is sectorised is designed to cope with this, so that if you have a glitch in one operations room, the whole of the UK is not affected.
He said flights could normally still continue to a limited extent. “Because of the sheer volume of traffic, the first way that we deal with it is flow control. They simply stop all of the traffic heading for airspace. If a plane’s on the ground it’s not a risk. But at its most basic, controllers can still talk to the airplanes because they’ve got radio systems.” “It sounds very much that it was the upper airspace sector which was affected, which means the contingency is that the London terminal area which handles the lower airspace would have taken over some of the flights.”
A computer problem affected operations at Swanwick for almost 12 hours last December, leaving thousands of passengers stranded as hundreds of flights were grounded.
Maclean said flights could normally still continue to a limited extent. “Because of the sheer volume of traffic, the first way that we deal with it is flow control. They simply stop all the traffic heading for airspace. If a plane’s on the ground it’s not a risk. But at its most basic, controllers can still talk to the planes because they’ve got radio systems.”
Prof Martyn Thomas, visiting professor of software engineering at Oxford University, said: “NATS has an outstanding safety record. They won’t have compromised safety, which always takes priority over delays, but delays were inevitable once the controllers lost the support of their computer-based tools, because without the tools the controllers cannot handle as many simultaneous aircraft.”
Aviation expert David Learmount told the BBC: “Because they don’t take any risks at air traffic control, they like to empty the skies. But because they have landed some planes, it shows they still have some capability.”Aviation expert David Learmount told the BBC: “Because they don’t take any risks at air traffic control, they like to empty the skies. But because they have landed some planes, it shows they still have some capability.”