Flights across the United Kingdom have been disrupted as the country’s air traffic control authority reported a technical issue, but later said the glitch had been resolved.
The National Air Traffic Services, or NATS, said in a statement on Wednesday that departures at all airports have resumed and that teams are working with affected airlines and airports to “clear the backlog safely”.
“Our systems are fully operational and air traffic capacity is returning to normal,” it said.
The outage, announced by NATS, included Heathrow Airport, Britain’s largest airport and Europe’s busiest.
“Flights at Heathrow have resumed following a technical issue at the NATS Swanwick air traffic control centre. We are advising passengers to check with their airline before travelling,” an airport spokesperson said.
Gatwick Airport and Edinburgh Airport also said operations were resuming.
ℹ️ Technical issue at Swanwick
Our systems are fully operational and air traffic capacity is returning to normal.
(1/2) https://t.co/69ftwzLeSK pic.twitter.com/KKDercVfqa— NATS (@NATS) July 30, 2025
London City Airport had earlier also reported disruption. It was not clear exactly how long the outage had lasted.
Ryanair said the disruption lasted for “over four hours” and caused delays and several diversions, inconveniencing thousands of passengers.
The Irish low-budget airline said the problem was “utterly unacceptable” and called for Martin Rolfe, the chief executive of the air traffic control provider, to resign.
“It is clear that no lessons have been learnt since the Aug ’23 NATS system outage and passengers continue to suffer as a result of Martin Rolfe’s incompetence,” Ryanair chief operating officer Neal McMahon said in a statement.
The NATS system has suffered several software-related failures since it opened in 2002.
In August 2023, flights across Britain were disrupted after the automatic processing of flight plans malfunctioned. Hundreds of flights were delayed or canceloed at the height of the summer holidays, and some 700,000 passengers were affected.
Britain’s aviation regulator last year said NATS needed to review its contingency plans for outages after the outage, which airline bosses said cost them over 100 million pounds ($133m) in refunds and compensation.
