UK air traffic system failure cancels over 1,000 flights and grounds departures across Europe

Technical failure and initial disruption

On Tuesday, 8 September 2026, a technical failure in the flight planning system operated by National Air Traffic Services (NATS) disrupted departures across British airports. The outage halted operations across 15 airports in the United Kingdom, including London Heathrow, Gatwick, Stansted, and Luton. Disruptions quickly spread beyond London to regional hubs including Edinburgh, Manchester, and Belfast, as well as Dublin Airport in Ireland. While incoming flights were largely able to land without major interference at Heathrow and Luton, departures stalled for hours, leaving thousands of passengers stranded on stationary aircraft. NATS identified the root cause in its flight data processing software and deployed recovery measures by late Tuesday afternoon.

We determined that the cause of the problem was our flight handling system. Our engineers are on site and working urgently to restore normal operations as quickly as possible.

Scope of cancellations and flight delays

The disruption led to over 1,000 cancelled flights across the United Kingdom on Tuesday, with Independent reporting approximately 1,300 cancellations. Ryanair cancelled over 200 flights, affecting roughly 150,000 passengers, while British Airways cancelled or diverted 100 services, affecting tens of thousands more. Flight tracking service Flightradar24 recorded multi-hour delays across European routes, including a British Airways departure from Heathrow to Warsaw that faced a four-hour delay and a Gatwick service to Zurich delayed by over three hours. Tabulated cancellations on Tuesday also grounded connections from Heathrow to Amsterdam, Edinburgh, and Zagreb. Although flight controls stabilized later in the evening, Heathrow remained unable to resume night flights.

Morning recovery and knock-on effects

By Wednesday, 9 September 2026, flight operations began to resume at Heathrow and Gatwick, though airline schedules remained heavily disrupted. Heathrow recorded 246 cancelled flights before 06:00 on Wednesday morning, with Gatwick logging another 33 cancellations. Carriers struggled to reposition aircraft and crews that were displaced during Tuesday's ground stops. British Airways cancelled morning departures to Barcelona, Crete, and Larnaca, while TAP Portugal cancelled flights to Lisbon, KLM scrapped an Amsterdam service, and LOT Polish Airlines cancelled its Heathrow service. Airport authorities warned passengers not to travel to terminals without verified flight confirmations from their airlines.

We are expecting a knock-on effect in connection with the repositioning of aircraft and crew.

Official response and industry scrutiny

NATS Chief Executive Martin Rolfe addressed the incident on Wednesday morning, stating that investigators had ruled out a cyberattack as the cause of the failure. Rolfe told BBC Radio 4 that the technical breakdown differed from previous disruptions that had affected British aviation. The incident renewed commercial pressure on NATS, which faced sharp criticism from carriers such as Ryanair and Wizz Air. Ryanair had previously demanded Rolfe's resignation following an August 2023 NATS flight plan failure that disrupted travel for 700,000 passengers and cost airlines over £100 million in refunds and compensation. That incident was followed in July 2025 by a radar failure that grounded UK flights for more than four hours.