Travel chaos at UK airports as air traffic control glitch cancels over 600 flights

National Air Traffic Services initially said the problem had been traced to its flight processing system and that engineers were working to restore normal operations.

In Short

• Heathrow sees cancellations, while Gatwick records hundreds of delays
• Edinburgh, Birmingham, Luton, Glasgow and Dublin airports also affected
• Air traffic body implements fix as flight systems gradually return toward normal

Hundreds of flights at major British airports faced delays and cancellations on Tuesday after a technical problem at air traffic control provider National Air Traffic Services (NATS) disrupted flight processing systems, affecting operations at Heathrow, Gatwick, Manchester, Stansted and several other airports.

Although flights continued to depart and British airspace remained open, the disruption caused widespread delays, with NATS later saying it had implemented a fix and that its systems were beginning to recover.

NATS initially said the problem had been traced to its flight processing system and that engineers were working to restore normal operations.

"We have identified that the issue was in our flight processing system. Our engineers are on site and working urgently to resume normal operations as quickly as possible," NATS said in a statement, as quoted by Reuters. "Flights are still departing and airspace is open, but recovery will take some time," it added.

Heathrow, Britain's largest airport, said it was coordinating with NATS to resolve the disruption. Flight-tracking website Flightradar24 said arrivals and departures were being regulated at airports across the London flight information region because of the technical problem.

The disruption quickly translated into significant delays and cancellations. FlightAware data showed that around 100 flights had been cancelled at Heathrow, while 367 were delayed.

At Gatwick, about 250 flights were delayed, accounting for roughly 31% of the airport's total flights. Nearly 300 cancellations were reported across affected airports by Tuesday afternoon as NATS systems began returning to normal.

Airports beyond London were also affected. Edinburgh Airport warned passengers that the technical issue could have an impact on its operations, while Dublin Airport said flights arriving from and departing for Britain were also facing disruption. Luton and Birmingham airports, along with Aberdeen and Glasgow, reported delays or cancellations.

Airlines were also forced to adjust their operations. British Airways said it was experiencing disruption because of the NATS problem.

"This is entirely out of our control, and we're in touch with our customers whilst our teams work to get them on their way as quickly as possible," the airline said in a statement cited by Reuters.

EasyJet said the issue was causing delays across Europe. British Airways accounted for 96 of the reported cancellations, followed by easyJet with 92, KLM with 20, Lufthansa with 12 and Swiss with 11.

The incident comes after previous technical failures have caused major disruption to Britain's aviation network. In 2024, the UK's aviation regulator said NATS needed to strengthen its contingency arrangements after a flight-plan processing malfunction the previous year created widespread chaos.

Airline executives estimated the earlier disruption cost the industry more than 100 million pounds in refunds and compensation. A radar-related technical problem in July last year also disrupted flights for more than four hours at Heathrow and other major airports.

NATS subsequently announced progress towards restoring normal operations. "We have implemented a fix and our flight system is starting to recover," NATS said in a post on X.

Airlines and airports are now expected to work through the backlog of delayed and cancelled flights, with passengers likely to face continued disruption as schedules are gradually brought back on track.

- Ends
With Reuters inputs