Heathrow and Gatwick hit by new air traffic control failure

Flights at London’s Heathrow and Gatwick airports have been heavily disrupted after a technical failure in the UK’s air traffic control system triggered mass cancellations, diversions and delays that are expected to ripple through schedules for several days.

Hundreds of flights cancelled as technical fault ripples across networks

Reports from flight tracking services indicate that more than 1,300 flights to and from UK airports were cancelled in the first 24 hours after the failure in the National Air Traffic Services (NATS) flight-processing system, with Heathrow and Gatwick among the worst affected hubs. Heathrow logged more than 200 cancellations and significant delays on subsequent rotations, while Gatwick reported dozens of axed services alongside widespread knock-on disruption.

The technical fault, which emerged around midday on Tuesday 8 September 2026, affected the processing of flight plans rather than radar coverage, prompting restrictions on departures and arrivals to maintain safety. Publicly available information shows that departures from Heathrow were paused for periods during the afternoon, while incoming flights were diverted to other airports including Stansted and Gatwick as capacity was sharply reduced.

Although NATS reported that the core system issue was resolved after several hours, schedules at both London hubs remained severely out of position into Wednesday. Data compiled by multiple outlets indicated several hundred additional cancellations and rolling delays as airlines attempted to reposition aircraft and crew, with some long-haul passengers facing overnight stays or multi-day rebookings.

The disruption has also spilled well beyond the UK. Major European and transatlantic services into Heathrow and Gatwick have been cancelled or delayed, with airports in Ireland and continental Europe reporting knock-on effects as aircraft and crews were left out of place.

Heathrow passengers face extended delays and diversions

Heathrow, one of Europe’s busiest international hubs, has borne the brunt of the latest failure. Flight monitoring data cited in published coverage shows that more than 240 Heathrow services were cancelled by early Wednesday morning, with further flights later removed from schedules as airlines reassessed operating capacity.

Some arriving long-haul flights bound for Heathrow were diverted to other UK airports when landing slots became unavailable during the height of the outage. Live travel feeds described aircraft from European and Mediterranean destinations diverting to Gatwick and Stansted, compounding congestion at those airports and leaving passengers waiting for ground transport or onward connections.

Heathrow’s public travel updates have urged passengers to check their flight status before setting out, and to travel to the airport only if their service is confirmed as operating. Additional terminal staff have been deployed to manage queues at check in, security and customer service desks, though images shared by broadcasters and on social media show crowded concourses and passengers attempting to sleep on terminal floors.

With aircraft and crew displaced around the network, analysts expect Heathrow’s operations to remain fragile for several days, even as air traffic control capacity returns to normal. Short-haul routes with high daily frequencies are likely to see rolling cancellations and retimed services as airlines work back toward regular patterns.

Gatwick disruption adds to pressure on UK south-east

Gatwick, the UK’s second-busiest airport and a major base for European leisure and low-cost carriers, has also experienced substantial disruption. Early figures from flight trackers and airport statements pointed to at least 30 cancellations and a high proportion of delayed departures and arrivals in the first phase of the crisis, particularly on short-haul routes to Ireland and mainland Europe.

Passengers at Gatwick described hours on board aircraft awaiting departure slots, followed by returns to gates and eventual cancellations in some cases. Visuals from the scene showed travellers stretched out on terminal floors amid long queues for food, water and rebooking assistance, highlighting the pressure on ground operations when large volumes of flights are halted at short notice.

While some services at Gatwick have resumed more quickly than at Heathrow, the airport has continued to warn of residual disruption and has advised passengers to monitor airline apps and websites closely. Low-cost and leisure carriers that operate tight turnarounds are particularly vulnerable to cascading delays when aircraft run late across multiple sectors in a single day.

The situation has revived scrutiny of previous staffing and systems issues around Gatwick’s airspace, where earlier summers saw repeated delays linked to air traffic control resource constraints. Industry groups argue that the latest technical fault, layered on top of capacity pressures, demonstrates the vulnerability of the south-east England air corridor to any system shock.

Recurring failures raise questions over NATS resilience

The latest outage is the third major breakdown attributed to the UK’s air traffic control systems in as many years, following a nationwide flight plan processing failure in 2023 and a radar-linked issue in 2024 that also caused widespread cancellations. Airlines and consumer advocates are now calling attention to what they describe as a pattern of repeated technical shocks affecting some of Europe’s busiest airspace.

Publicly available statements from NATS indicate that the current incident originated in its flight data processing system, which handles the filing and coordination of flight plans used to manage traffic flows. Cyber attack has been ruled out in early assessments, with the problem instead attributed to a technical glitch that forced operations onto fallback procedures and curtailed capacity.

Industry bodies representing UK airlines have urged the government to tighten oversight of NATS’s contingency planning and investment in redundancy, citing the cost of previous failures that ran to hundreds of millions of pounds in refunds, accommodation and operational disruption. Carriers argue that, although safety-critical systems must err on the side of caution, repeated large-scale shutdowns impose unacceptable uncertainty on passengers and the wider travel sector.

Regulators have previously instructed NATS to review its backup arrangements after earlier incidents, and questions are now being raised in parliament and the media over whether those recommendations were implemented sufficiently to prevent further failures. Analysts note that as traffic levels recover to, and in some cases exceed, pre-pandemic volumes, even short interruptions in capacity can quickly cascade into multi-day disruption.

What affected passengers at Heathrow and Gatwick can expect

Travel rights experts note that because the cause of the disruption lies with air traffic control rather than individual airlines, compensation under UK and EU air passenger rules is likely to be limited in many cases. Guidance from consumer groups suggests that passengers may still be entitled to care and assistance, including refreshments, communication, and accommodation for overnight delays, depending on the length and circumstances of the disruption.

Advisers stress that affected travellers should retain boarding passes, booking confirmations and receipts for any essential expenses, as airlines may request documentation for reimbursement claims. Some legal specialists also recommend that passengers check travel insurance policies, which may cover additional costs such as missed connections, prepaid accommodation at destinations or alternative transport arrangements.

For those with upcoming flights through Heathrow and Gatwick, publicly available travel bulletins consistently highlight the importance of checking real-time information before setting out. Many airlines are allowing free rebooking or waiving change fees for passengers willing to switch to alternative dates or airports while schedules remain unstable.

Operational updates from airports and carriers indicate that while the worst of the ground stop has eased, irregular operations are likely to persist for several days as airlines reposition aircraft and crew and as slot allocations are adjusted. Travellers passing through Heathrow and Gatwick in the coming week are being advised to allow extra time, travel with flexible plans where possible and prepare for continued queues at check in, security and customer service desks.

Independent: Heathrow and Gatwick delays live coverage

The National: Hundreds of flights cancelled after air-traffic control issue

Euronews: Technical glitch leads to more than 1,000 UK flight cancellations

Sky News: UK airports disruption after air traffic control failure