Flights grounded across the UK as NATS system failure hits major airports

Flights across the UK have been delayed after a technical problem affected the NATS flight processing system, triggering restrictions at major airports including Heathrow, Gatwick, Stansted and Manchester.

The disruption began on Tuesday afternoon, with aircraft held at departure gates or on taxiways while the UK’s air traffic control provider reduced the number of flights entering parts of the network.

NATS initially described the incident as a technical issue before confirming that the problem had been traced to its flight processing system.

“We have identified that the issue was in our flight processing system,” NATS said in an update at 3:25 pm. “Our engineers are on site and working urgently to resume normal operations as quickly as possible.”

The organisation said UK airspace remained open and flights were still departing, but warned that recovery would take time.

Why are flights delayed at UK airports today?

Flight processing systems help air traffic controllers receive and manage the information needed to safely coordinate aircraft through controlled airspace.

When that capability is reduced, NATS can impose traffic restrictions to ensure controllers are not presented with more aircraft than the available systems can safely handle. This can substantially reduce the number of departures permitted during a given period, even though the airspace itself has not formally closed.

The disruption has mainly affected departing flights, although traffic restrictions have also had consequences for inbound aircraft.

Initial Cirium data showed that 45 scheduled departures from Heathrow and Gatwick had been cancelled or classified as non-operating by 16:15 on 8 September.

Heathrow accounted for 37 of those flights, representing 5.6% of its 661 scheduled departures. Gatwick had eight affected departures from a planned total of 376, equivalent to 2.13%.

Cirium also identified 38 cancelled or non-operating arrivals at Heathrow and six at Gatwick.

Some passengers reported being held aboard aircraft before disembarking and returning to the terminal, while other flights remained at their gates awaiting revised departure times.

Heathrow, Gatwick and other UK airports affected by NATS disruption

Heathrow initially said departing flights were affected, but arrivals were continuing. However, Flightradar24 subsequently reported that Eurocontrol had listed Heathrow as unavailable for arrivals between 2 pm and 4 pm UTC, with some inbound aircraft holding or diverting.

Eurocontrol now lists London-Heathrow as unavailable for arrivals between 1400-1600 UTC. Inbound flights currently holding or diverting. https://t.co/TEHf2kJO23 pic.twitter.com/i5vhyxZPzN

— Flightradar24 (@flightradar24) September 8, 2026

Other London-area airports affected included Gatwick, Stansted and Luton. Disruption was also reported at Manchester, Birmingham, Belfast City, Edinburgh, Glasgow, Aberdeen, Southampton, East Midlands and Jersey. Flights to and from Dublin were affected because many services use UK-controlled airspace.

British Airways confirmed that its schedule had been disrupted by the NATS problem and said its teams were working to get passengers’ travel plans back on track.

Even after the technical issue is resolved, delays may continue as airports and airlines reposition aircraft and crews and work through queues of waiting departures.

Is the NATS technical problem a cyberattack?

NATS has not confirmed the underlying cause of the flight processing system problem.

There is currently no official evidence that the disruption was caused by a cyberattack. NATS has described it only as a technical issue and said it will release further information once the details have been confirmed.

The incident comes shortly after Manchester Airports Group disclosed a significant cyberattack affecting customer data associated with Manchester, Stansted and East Midlands airports. However, there is currently no confirmed connection between that incident and the NATS disruption.

What are your rights if your flight is delayed by the NATS failure?

Passengers should check their flight’s status with the airline before travelling to the airport. Unless the airline says otherwise, they should still arrive in time for check-in and boarding: a general airport delay is not permission to turn up late.

Flights departing from a UK airport are covered by UK261, irrespective of the airline operating them. The rules require airlines to look after passengers during a sufficiently long delay, even when the disruption was caused by air traffic control and was outside the airline’s control.

The right to food, drink and communication begins after:

• Two hours for flights of less than 1,500 km
• Three hours for flights between 1,500 km and 3,500 km
• Four hours for flights of more than 3,500 km

If the airline does not provide vouchers or assistance, passengers can buy reasonable food and refreshments and claim the cost back. Itemised receipts should be retained, while alcohol, expensive meals and luxury accommodation should be avoided.

If the disruption extends overnight, the airline must provide reasonable hotel accommodation and transport between the airport and hotel. This duty continues even when the airline is not responsible for the original disruption.

What happens if a flight is cancelled?

If a flight covered by UK261 is cancelled, the airline must offer a choice between a refund and alternative transport.

Passengers who still need to travel can ask to be rerouted at the earliest opportunity, rather than automatically accepting the airline’s next available service. The UK Civil Aviation Authority says this may include another airline, or another suitable form of transport, if it would get the passenger to their destination significantly sooner.

The airline must continue providing food, accommodation and other reasonable care while the passenger waits for the replacement journey.

Passengers should contact the airline before buying their own replacement ticket. If the airline refuses or is impossible to reach, they should retain screenshots of the alternatives offered, records of attempts to contact it and receipts for any reasonable replacement arrangements.

Can passengers claim compensation for the NATS disruption?

Fixed compensation under UK261 or EU261 is unlikely to be payable where a delay or cancellation was directly caused by the NATS failure.

Air traffic management restrictions are normally treated as extraordinary circumstances because they are outside an airline’s control. However, airlines cannot reject every claim merely by referring to “air traffic control”. They must show that the NATS disruption caused the particular delay or cancellation and that reasonable measures could not have avoided it.

If a flight’s disruption was extended by a separate problem within the airline’s control, such as unavailable crew or an aircraft fault, passengers may still have grounds to claim.

Crucially, extraordinary circumstances affect cash compensation, not the rights to meals, accommodation, rerouting or a refund. Those obligations remain in force. The details are set out in the UK Civil Aviation Authority’s delay guidance, CAA cancellation guidance and the European Commission’s EU261 guidance.

Previous NATS failures caused widespread flight cancellations

In August 2023, an unusual flight plan caused the primary and backup NATS processing systems to enter fail-safe mode. More than 1,600 flights were cancelled, and over 700,000 passengers were affected.

A separate radar-related technical problem disrupted flights at Heathrow and other major UK airports for several hours in July 2025.

NATS apologised for the latest disruption and said it was working urgently to restore normal operations. Further updates are expected through the NATS website and its official social media channels.