UK Flight Chaos Enters Day Two After NATS Glitch

A technical fault at UK air traffic control cancelled nearly 2,000 flights over two days, with disruption and political fallout continuing into Wednesday.

Britain's air traffic control provider NATS suffered a technical glitch in its flight data processing system on Tuesday, September 8, first reported around 1:45pm, according to the Manchester Evening News. By the time the issue was fixed that evening, more than 1,750 flights had been cancelled on Tuesday and a further 153 were axed on Wednesday, according to aviation analytics firm Cirium, cited by the BBC. Heathrow suspended arrivals, departures were repeatedly paused, and 13 Heathrow-bound flights were diverted to other sites in the UK and Europe. Airports in Ireland, including Dublin, also reported disruption.

The outage is the third major NATS failure in recent years, which is why airlines reacted with such fury rather than treating it as an isolated mishap. In 2023, a computer shutdown over the August bank holiday weekend disrupted 700,000 passengers, and there was a smaller NATS outage in 2025 that caused 150 cancellations, the BBC reports. Wizz Air UK managing director Yvonne Moynihan told the BBC that 'in any position where you've had three failures you need to consider three strikes and your out,' urging NATS chief executive Martin Rolfe to consider his position. CNN notes UK airports have endured major outages on a yearly basis since 2023.

The numbers across outlets show the scale. The Guardian, citing Cirium, reported more than 1,900 flights cancelled by 5am Wednesday — 902 departures and 860 arrivals on Tuesday out of 5,800 scheduled, versus a normal cancellation rate of under 1–2%. Flightradar24 figures reported by CNN put Tuesday's cancellations at around 1,300, with 177 axed on Wednesday, nearly all at Heathrow. EasyJet made 200 cancellations and British Airways more than 100, while Ryanair said more than 65,000 of its passengers were delayed by up to eight hours, according to the BBC. Singapore Airlines told The Straits Times that two flights were diverted to Paris and Munich and two return flights cancelled.

The government response escalated quickly. Transport Secretary Heidi Alexander summoned Rolfe to a meeting to explain what happened and was expected to tell the House of Commons on Wednesday that a cyber attack was 'categorically' not the cause, the BBC reports. Foreign Secretary Ed Miliband called the situation 'frankly unacceptable' and apologised to passengers, according to both the BBC and The Guardian. Ryanair's chief operating officer Neal McMahon went further, telling CNN that NATS' chief executive should be fired, while Euronews quotes him saying it is 'time for the UK government to intervene.' Rolfe defended the organisation, saying the UK has 'one of the best systems in the world.'

The human toll ran from tarmac strandings to missed events. Passengers described scenes the Manchester Evening News characterised as 'pure chaos,' with some stuck on stationary planes for more than four hours before flights were cancelled. One traveller, Josie Donoghue, told the Associated Press, as quoted by CNN and Euronews, that getting through Gatwick was 'like trying to get out of Alcatraz.' Arsenal's Champions League trip to Napoli was disrupted enough that the team cancelled a pre-match news conference, Euronews reports. Heathrow advised passengers to travel only with a confirmed operating flight, and airlines warned call centres were overwhelmed.

NATS says the technical issue is resolved and it is working to clear the backlog, but all outlets agree knock-on disruption will persist as airlines reposition aircraft and crew. The Guardian reported Transport Secretary Alexander is seeking answers on system resilience, and a full investigation has been promised by Rolfe, per the BBC. Wizz Air's Moynihan told the BBC that serious questions remain about 'the resilience of the system' and that leadership must show accountability. Travellers are being advised to check directly with airlines before heading to airports, as rescheduled flights may make terminals busier even on days with a nominally full schedule.