Britain's Flight Control System Just Failed Twice in 13 Days, Here's What That Actually Means If You're Flying This Autumn

NATS, the company that runs UK air traffic control, suffered its second major system failure in thirteen days on 21 September 2026, when a network fault at its Prestwick centre cut UK airspace capacity by 60 percent and disrupted more than 25,000 Ryanair passengers alone. If you are flying to, from or through the UK this autumn — including on a route connecting to a Nepal trek — you are not entitled to compensation for either failure, because air traffic control faults count as “extraordinary circumstances” under UK261. Airlines still owe you care while you wait: meals, communication, and a hotel with transfers if you are stranded overnight.

What actually broke at NATS on 8 and 21 September

Two separate, unrelated faults hit Britain’s single air navigation provider in less than a fortnight. On 8 September, NATS says a manual request for an aircraft identification “squawk” code overlapped with a higher-priority system process for approximately one millisecond, corrupting data inside the flight-processing system. Airspace flow restrictions ran until roughly 7:30pm that evening, and more than 2,000 flights were cancelled, delayed or diverted across Heathrow, Gatwick, Manchester, Birmingham, Edinburgh, Luton and Bristol, with knock-on aircraft and crew positioning problems lasting days. NATS published its preliminary findings on 18 September.

On 21 September, a different and unrelated connectivity issue hit the Flight Data Processing System at NATS’s Prestwick centre in Scotland. This one was geographically concentrated: Scotland, Northern Ireland, northern England and parts of the North Atlantic bore the brunt, while airports south of Manchester were largely unaffected. Edinburgh, Glasgow, Belfast International and Manchester saw the worst disruption, transatlantic routes between northern Europe and the US were restricted, and Ryanair alone reported over 140 delayed flights and more than 25,000 passengers hit. EasyJet and British Airways also cancelled and delayed services.

Why this keeps happening, and what regulators had just signed off

This is the third national-level NATS failure since 2023, and the timing is the part worth knowing. The UK’s Civil Aviation Authority ran an independent review into the August 2023 NATS failure — the one that stranded around 700,000 passengers over a bank holiday weekend — and issued 34 recommendations. The CAA confirmed in June 2026 that every one of those recommendations was either completed or embedded into its ongoing regulatory programme. Thirteen weeks later, NATS failed twice in thirteen days. The UK government has now asked the CAA to run a fresh independent review of the 8 September incident, with findings expected within six months.

Are you owed compensation for either failure

No, not the fixed cash payout most flyers expect. The UK Civil Aviation Authority explicitly lists air traffic control disruption alongside severe weather and security incidents as an “extraordinary circumstance” under UK261 — the rule that normally forces an airline to pay a set amount for a cancelled or badly delayed flight. When the cause is outside the airline’s control, that fixed payment does not apply, and the CAA says passengers “are unlikely to be entitled to compensation” for delays or cancellations directly caused by either NATS incident.

What this means if you're connecting through the UK to Nepal this autumn

What this means for you

Most Everest and Annapurna trekkers flying from the US, Canada or continental Europe route through a UK or Gulf hub before Kathmandu. A NATS-triggered delay in London or Manchester will not cost you compensation, but it can cost you your onward connection and your first acclimatisation day on the trail. Build in at least one buffer night before your international connecting flight this autumn rather than a same-day transfer, keep your airline’s app open for gate changes, and confirm your operator’s policy on a missed first trekking day — ours allows a group to absorb one late arrival without losing the itinerary.

Frequently asked questions

Is NATS likely to fail again this autumn

Nobody can promise it won’t. Two unrelated systems failed in thirteen days after a full slate of post-2023 fixes was signed off, which is why the government has ordered a fresh independent review rather than accepting NATS’s own preliminary report as the last word.

Does travel insurance cover a NATS-caused delay

Most standard travel insurance policies cover reasonable extra expenses for a significant delay regardless of cause, which is separate from UK261 and not affected by the “extraordinary circumstances” classification — check your own policy’s delay-trigger threshold, typically 12 hours.

Which UK airports were affected

8 September hit Heathrow, Gatwick, Manchester, Birmingham, Edinburgh, Luton and Bristol nationwide. 21 September was concentrated on Scotland, Northern Ireland and northern England — Edinburgh, Glasgow, Belfast International and Manchester — with airports south of Manchester largely unaffected.

Cover photo: Quynh Tran via Pexels (Pexels License). Section photos: Holiday Extras via Pexels (Pexels licence); Magda Ehlers via Pexels (Pexels licence); Martijn Stoof via Pexels (Pexels licence); dongfang xiaowu via Pexels (Pexels licence); Harm Jakob Tolsma via Pexels (Pexels licence).