London airspace shutdown, computer fault locks system
London's airspace was closed this afternoon due to what authorities said was a computer failure at one of Britain's two air traffic control centers.
Officials at London Heathrow Airport said there was a power outage at the NATS control center in Swanwick, England and their statement gave no indication how long the situation was expected to continue.
NATS controls all of British airspace from two centers, one in Swanwick and another in Scotland.
The shutdown came at a busy time at the start of the weekend in a sprawling city with five commercial airports, including London Heathrow — Europe's busiest — as well as Gatwick, Luton, Stansted and London City Airports.
The NATS control center said "a technical problem has been reported at Swanwick air traffic control center" and an incident response team has been mobilised.
"Every possible action is being taken to assist in resolving the situation and to confirm the details," the control center statement said.
Last December, a computer problem at Swanwick took 12 hours to fix.
European air traffic control agency Eurocontrol said the London airspace was closed.
The Heathrow statement said "flights are currently experiencing delays and we will update passengers as soon as we have more information."
Airline security analyst Chris Yates said planes on the ground will not take off as they have no air traffic control cover.
Those in the air that are close enough to the airport to have been in a holding pattern — say within 30 minutes of landing — will be allowed to land, he said.
Those further out will have to be diverted to other airports.
Manchester Airport is open and accepting flights.
Yates said such computer issues happen rarely.
One that occurred about 2 1/2 years ago resulted in disruptions that lasted for days.
At Heathrow, passengers on United flight 941 to Newark were told about the computer problem as they boarded at 1530 GMT (10:30 am EST).
United gate staff said the plane would be loaded with passengers and head toward a runway in the hopes that the computer problem could be fixed.
Most passengers at Heathrow seemed unaware of the issue and no further mention was made during normal boarding.
The Swanwick center has been plagued by problems since it opened more than a decade ago.
It only swung into operation in 2002 — six years after its planned commissioning date and double its original budget.
Software and reliability issues have caused repeated disruption since.
A few months after its opening, the BBC cited an unnamed air traffic controller as complaining of "potentially catastrophic" problems at the facility, including erratic radio transmissions.
Other controllers cited by the broadcaster said the text on their computer screens was "too tiny to read."
In 2004, Swanwick was in the news again when a computer problem grounded scores of flights across Britain.
An even more serious glitch in September 2008 grounded hundreds of flights and affected tens of thousands of travelers.
The 2013 failure at Swanwick was particularly bad because it came at the beginning of the holiday season.
After calm was restored, NATS chief Richard Deakin called that failure a "one-in-10-year event."