Flight delays are expected to continue on Wednesday following an air traffic control problem in the UK that resulted in nearly 2,000 flight cancellations. According to aviation analytics firm Cirium, over 1,750 flights were cancelled on Tuesday, with an additional 153 cancellations reported on Wednesday. Nats, the air traffic control provider, attributed the disruptions to a technical glitch, and its CEO Martin Rolfe issued an apology, stating that a full investigation would be conducted as resolving the issue took longer than anticipated.
Foreign Secretary Ed Miliband described the situation as "frankly unacceptable," and Transport Secretary Heidi Alexander has called for a meeting with Rolfe to discuss the incident. Alexander is scheduled to address the House of Commons on Wednesday regarding the disruptions and is expected to clarify that a cyber attack was "categorically" not the cause of the fault.
Passengers are advised to check with their airlines for updates, as it may take time for flights to return to normal operations. Heathrow Airport has advised that travelers should only come to the airport if they have a confirmed flight. Due to the limited number of aircraft able to take off, landings were also restricted, causing some flights to be unable to depart from overseas airports.
The technical fault affected airports across the UK and beyond, including reports of disruptions in Ireland. EasyJet cancelled 200 flights, while British Airways cancelled more than 100. This incident is not the first disruption for Nats; in 2023, a computer shutdown during the August bank holiday weekend affected 700,000 passengers, and a smaller outage occurred in 2025, leading to 150 cancellations.
Ryanair and Wizz Air have called for an overhaul of Nats, with Wizz Air's managing director Yvonne Moynihan stating that the current system is "not fit for purpose." Moynihan also suggested that Rolfe should consider his position following the repeated failures. Rolfe, when asked about his position, stated that his focus was on resolving the current issue, emphasizing that the UK generally has a strong air traffic system.
Ryanair reported that over 65,000 passengers experienced delays of up to eight hours. At Heathrow, one of Europe's busiest airports, departures were paused around lunchtime before resuming, although further disruptions occurred later in the afternoon due to a backlog of incoming flights. A spokesperson for Heathrow indicated that operations were recovering, while London Gatwick reported that flights had resumed but full operations would take time to normalize.
British Airways acknowledged the anticipated knock-on effects from the disruptions, stating that they had to cancel or divert over 100 flights on Tuesday afternoon. They urged customers whose flights were cancelled not to travel to the airport and to be patient with their busy call centers. Phil White, a passenger affected by the delays, reported being stuck on the tarmac at Gatwick for hours due to the radar issues.
Despite the resolution of the technical issue, backlogs are likely to prolong the disruptions, as both departures and arrivals were impacted due to limited space on the ground. Rolfe clarified that the issue was related to Nats' flight data processing system, which is different from the system that failed in 2023. Additional reporting was provided by Emer Moreau, Faarea Masud, and Nick Watt.