Full Breakdown
Major UK Air-Traffic Control Glitch Halts Thousands of Flights
By Drooid · · How we work
The Outage and Immediate Impact
On Tuesday, September 8, a technical fault in the flight-processing system of National Air Traffic Services (NATS) disrupted operations at 15 UK airports, including Heathrow, Gatwick, Stansted, Manchester and Birmingham. Departures were halted for several hours while arrivals were suspended at Heathrow. Passengers were left on the tarmac for up to six hours, many sleeping on airport floors. The incident forced airlines to cancel or divert hundreds of flights and created a backlog that persisted into the following day.
Background: Prior NATS Failures
NATS has experienced three major outages in the past three years: a radar-related failure in July 2025, a widespread glitch in August 2023 that stranded over 700,000 travellers, and the September 8 fault. Each episode prompted calls for stronger contingency planning and highlighted the provider’s reliance on a single flight-plan processing node at its Swanwick centre.
Data & Statistics
- 1,300 flights cancelled on Tuesday, with an additional 177 the next day.
- Cirium reported a total of 1,750 cancellations on Tuesday and 291 more on Wednesday, roughly 2,040 flights over two days.
- Airlines UK estimated more than 330,000 passengers were affected, including 155,000 cancellations and 180,000 delays.
- Ryanair disclosed over 65,000 of its passengers were disrupted and more than 50 scheduled flights were cancelled.
- British Airways cancelled almost 550 flights, impacting over 85,000 customers.
Official Statements & Responses
NATS said the issue was identified in its flight-processing system and engineers resolved it by the evening, but warned that “recovery will take some time.” The organisation later called the outage “very complex” and apologized to passengers, airlines and airports. The Civil Aviation Authority (CAA) indicated the disruption is likely to be classified as “extraordinary circumstances,” limiting compensation claims. British Airways described the incident as “entirely out of our control” and expressed regret for the impact on its customers.
Criticism & Opposition
Ryanair’s chief operating officer Neal McMahon condemned the failure as “abhorrent” and called for NATS chief executive Martin Rolfe to resign. Ryanair CEO Michael O’Leary echoed the demand, labeling Rolfe “overpaid” and accusing the government of shielding him. Wizz Air said NATS is “simply not fit for purpose” and urged urgent reform. Industry groups, including the travel association ABTA, warned that repeated outages erode public confidence and called for accountability.
Conflicting Reports & Gaps
Sources differ on the total number of flights cancelled. Reuters cited 1,300 cancellations on Tuesday, while Cirium’s data placed the figure at 1,750 for the same day. The Guardian reported “more than 2,000 flights” affected across the two days, whereas the Independent noted 2,163 flights impacted. These discrepancies stem from varying definitions of “cancellation” versus “delay” and the timing of data collection, leaving the precise scale of the outage unsettled.
What’s Next
Transport Secretary Alexander has given NATS chief Martin Rolfe one week to submit a detailed report on the cause of the September 8 fault. The CAA will conduct an independent review and present findings to Parliament within six months. NATS has pledged a full investigation and indicated that any future system upgrades will undergo rigorous testing to prevent recurrence. Airlines continue to adjust schedules, and passengers are advised to monitor airline communications for further updates.
