Air traffic control failure grounds Gatwick departures – what Kent passengers are owed

More than 1,300 flights were cancelled on Tuesday after a technical failure at NATS, the company that runs the UK’s air traffic control, grounded departures at Gatwick and every other major British airport. At least a further 177 were cancelled on Wednesday as the backlog cleared, according to flight-tracking service Flightradar24.

Gatwick — the closest large airport for much of Kent — was among the worst affected. The airport confirmed the problem in a statement, saying: “We are aware of a NATS technical issue that is currently affecting a number of UK airports, including London Gatwick.”

Transport Secretary Heidi Alexander summoned NATS chief executive Martin Rolfe to an emergency meeting on Wednesday morning, and told MPs the government had “categorically” ruled out a cyber attack.

What went wrong

NATS first reported the problem at 13:46 on Tuesday 8 September, saying it was “investigating a technical issue which is causing some disruption to flight departures” and that engineers were on site.

At 15:25 the organisation identified where the fault lay. “We have identified that the issue was in our flight processing system,” NATS said. “Our engineers are on site and working urgently to resume normal operations as quickly as possible.” It added that “flights are still departing and airspace is open, but recovery will take some time.”

The failure was in the system that processes flight plans, not in radar or radio communications. With automatic processing unavailable, controllers reverted to entering flight plans manually — which cannot be done at anything like the same rate. Departures were therefore metered or held to keep traffic at a level controllers could safely handle. Arriving flights were largely unaffected; Heathrow confirmed that “arriving flights are not currently impacted”.

NATS reported a fix at 16:40, but the disruption outlasted the fault by many hours. At 19:30 it said “recovery from today’s system issue has taken longer than we had hoped”, and at 22:10 that work was “continuing to assist airlines and airports recover from today’s disruption”. It described the episode as “a very complex recovery” that “has created difficulties for the whole aviation network, from which it will take time to recover”. The organisation apologised, saying: “We recognise the ongoing disruption to travel, for which we sincerely apologise.”

What caused it — and what did not

Two things are now established. The first is what did not cause it: Ms Alexander told MPs on Wednesday that a cyber attack had been “categorically” ruled out. Officials have pointed instead to an internal software malfunction.

The second is that, more than a day after the event, NATS has not said what did cause it. Mr Rolfe told Sky News that the organisation had not “fully done the investigation”, adding: “We don’t have an idea yet of exactly what went wrong.”

That matters because the same class of system failed three years ago, and on that occasion the cause was eventually pinned down in detail. NATS’ report into the August 2023 collapse traced it to a sub-system called Flight Plan Reception Suite Automated — Replacement, or FPRSA-R, which met a flight plan containing two identically named waypoint markers in different places outside UK airspace. The software raised a critical exception, and both the primary system and its backup shut themselves into a fail-safe mode at the same time.

Until NATS publishes its findings on Tuesday’s failure, there is no basis for saying whether the two events share a cause. What can be said is that both sat in flight plan processing rather than in radar or communications, and that both took down the automated path and left controllers working by hand.

How Kent was affected

Kent has no major commercial passenger airport of its own — Manston closed in 2014 — so Kent residents fly from airports outside the county. On Tuesday, every one of the airports Kent travellers typically use appeared on the affected list: Gatwick, Heathrow, Stansted, London City and Southend, alongside Manchester, Birmingham, Bristol, East Midlands, Aberdeen, Edinburgh and Jersey.

The fault struck in the early afternoon, when short-haul departures to European destinations are at their heaviest and passengers were already travelling to the airport for evening flights. The backlog then took far longer to clear than the outage itself lasted: aircraft and crews end up out of position, and crew duty-hour limits can force late cancellations even when runways are open. That is why flights were still being cancelled on Wednesday.

The aviation analyst John Strickland summed up the arithmetic: “A few hours of outage may on the face of it sound limited but the impact is enormous when a substantial number of airports across the UK are affected.”

What you are owed — and what you are not

This is the part most passengers get wrong, and it matters for anyone in Kent whose flight was cancelled or badly delayed.

An air traffic control failure is treated as an “extraordinary circumstance” under UK261, the retained passenger rights rules. That means airlines are not required to pay the fixed cash compensation of up to £520 that applies to delays and cancellations within their control.

The duty of care obligations, however, still apply in full, and they do not depend on whose fault the disruption was. If your flight was delayed beyond the relevant threshold, your airline must provide food and drink appropriate to the wait, and a means of communication. If you were forced to stay overnight, the airline must provide hotel accommodation and transport to and from it. If your flight was cancelled, you are entitled to choose between a full refund and re-routing to your destination at the earliest opportunity, including on another airline where necessary.

If an airline refuses to arrange accommodation or a re-route, passengers can pay for reasonable alternatives themselves and claim the cost back — keeping every receipt. The Civil Aviation Authority publishes the full rules, and complaints that an airline will not resolve can be escalated to an alternative dispute resolution body or to the CAA’s own passenger advice team.

Airlines turn on NATS

Ryanair said more than 50 of its flights were cancelled and over 65,000 of its passengers were hit by delays of up to eight hours. In a statement issued by the airline, its chief operations officer, Neal McMahon, gave Ryanair’s view that “despite promises, reports and assurances that they would fix the systems, once again NATS, under Martin Rolfe’s leadership have failed UK travellers”. That is the company’s characterisation, not a finding of fact, and Ryanair has been a longstanding critic of NATS. The airline repeated its call for Mr Rolfe to resign. Wizz Air, in its own statement, said it considered NATS “not fit for purpose”.

NATS has not responded to the resignation calls. Its published position remains the operational statements and the apology it issued during and after the disruption.

The third failure in three years

On the reported record, Tuesday’s outage is at least the third significant NATS technical failure since 2023, and the second to involve flight plan data. That is a characterisation drawn from the publicly reported incidents below rather than a regulatory finding; the CAA has not classified the three events together.

The August 2023 collapse led to more than 2,000 cancellations over the bank holiday. The Civil Aviation Authority estimated that more than 700,000 passengers were affected, and the cost to the industry has been estimated by industry analysts, in figures widely reported at the time, at over £100 million — an estimate rather than an audited total. The regulator commissioned an independent review, chaired by Jeff Halliwell, which reported with 34 recommendations directed at NATS, airlines and airports, the CAA itself and government.

In July 2025 a radar problem at the same Swanwick control centre forced NATS to restrict the number of aircraft in the London area, cancelling more than 150 flights. Airlines including Ryanair publicly stated at the time that NATS had failed to learn from 2023, and Ryanair called for the head of the service to resign then too. Those were the airlines’ stated positions.

The CAA has said it expects NATS to provide a full report on Tuesday’s incident, after which it will consider whether further steps are needed to secure the reliability of the UK’s air traffic control system.

What happens next

NATS has said its systems are operating normally and that the backlog has been worked through. Passengers due to fly should still check the status of their flight directly with their airline before travelling to the airport, rather than relying on general airport updates.

The substantive questions now sit with NATS’ report to the regulator: what failed, whether it was foreseen, and which of the 34 recommendations from the 2023 review had been implemented before Tuesday. Kent Local News will report on those findings when they are published.

Key information

• Fault reported by NATS: 13:46, Tuesday 8 September 2026
• Cause located to the flight processing system: 15:25 — fix implemented 16:40
• Flights cancelled Tuesday: more than 1,300 (Flightradar24)
• Flights cancelled Wednesday as the backlog cleared: at least 177 (Flightradar24)
• Cyber attack: “categorically” ruled out by the Transport Secretary
• Root cause: not yet established — NATS says its investigation is incomplete
• Airports affected include: Gatwick, Heathrow, Stansted, London City, Southend, Manchester, Birmingham, Bristol, East Midlands, Aberdeen, Edinburgh, Jersey
• UK261 cash compensation: not payable — air traffic control failure is an extraordinary circumstance
• Duty of care (meals, hotel, re-routing or refund): still owed by your airline
• Previous NATS failures: 28 August 2023 (2,000+ cancellations) and July 2025 (150+ cancellations)

Sources

• NATS — Technical issue causing some disruption to flight departures (statements timed 13:46, 15:25, 16:40 and 22:10, 8 September 2026)
• Al Jazeera — Hundreds of flights delayed, cancelled after UK air traffic control glitch (cancellation figures, Ryanair and analyst comment)
• AirLive — Transport Secretary summons NATS chief to urgent morning meeting after flight chaos
• LBC — Disruption at UK airports including Heathrow and Gatwick (airport statements)
• NATS — Report into the August 2023 air traffic control incident: root cause and solution implemented
• Civil Aviation Authority — Delays and cancellations: your rights
• Civil Aviation Authority — Independent Review into the August 2023 NATS Flight Planning System Failure