A single rogue flight plan caused the IT meltdown which led to many flight cancellations, it emerged last night.
The National Air Traffic Service (Nats) revealed that a “technical issue” that led to more than 1,000 flight cancellations was caused by “some of the flight data we received”.
The controller did not reveal further details, but the Telegraph understands it relates to a single piece of corrupt data from one airline.
Nats receives around 6,000 flight plans every day for planes departing and arriving in the UK.
More than 1,500 flights or a third of all journeys were cancelled on Monday, according to data aviation company Cirium, with hundreds more journeys, including some long-haul routes, axed on Tuesday with passengers forced to sleep on the floor in airports overnight.
The Prime Minister’s official spokesman has refused to rule out suggestions that a flight plan by a French carrier may have corrupted the system.
Speculation
Mr Sunak’s spokesman said: “I’ve seen, obviously, various bits of speculation, but I’m not going to pre-empt the work that needs to be done.”
However, he added that experts had confirmed it was a “technical issue, not a cybersecurity incident”.
Asked if officials would speak to counterparts across the English Channel, the spokesman said “you would expect them to be speaking regularly” with other countries “but I’m not aware of any specific conversations with French counterparts”.
Airlines are required to submit flight plans of their routes which must be approved before take off to ensure air space is safe.
Issuing a statement to explain the disruption, Martin Rolfe, the chief executive of Nats, said he wanted to “reassure” people that systems were now running normally.
He added: “Initial investigations into the problem show it relates to some of the flight data we received.
Systems
“Our systems, both primary and the back-ups, responded by suspending automatic processing to ensure that no incorrect safety-related information could be presented to an air traffic controller or impact the rest of the air-traffic system.”
Paul Charles, a travel consultant, said “rogue information caused the outage”.
“One particular flight plan, whoever it was from, corrupted the whole system” he told the Telegraph.
“Wherever it is from, it is an international embarrassment that our whole air-traffic system collapsed because of one flight plan. Without a doubt it’s one rogue file that came in and caused the whole system to freeze up.”
Disruption
Michael O’Leary, chief executive of Ryanair, has criticised Nats for the “unacceptable” disruption caused over the past two days.
He said his group had had “a very difficult day” with 250 of its flights cancelled on Monday, and a further 70 axed on Tuesday.
His comments were echoed by Willie Walsh, the director general of the International Air Transport Association and former boss of British Airways, who said the problem was “unacceptable”.