A technical failure in the NATS air traffic control flight data system halted flights across the United Kingdom on September 8 and 9, 2026, leading to the cancellation of more than 2,000 flights and causing widespread delays.
Impact on UK Airports and Airlines
The outage primarily affected London’s Heathrow and Gatwick airports, two of the country’s busiest hubs. Cirium, an aviation analytics firm, confirmed that 30% of scheduled departures on September 8 were grounded, with 5% delayed or canceled the following day, September 9.
Ryanair was the worst hit carrier, canceling 260 flights and disrupting travel for approximately 48,000 passengers. The airline reported estimated losses of
£3 million due to the system failure. British Airways canceled or diverted around 100 flights on the first affected day and canceled an additional 190 flights on the second day, further contributing to operational challenges at major UK airports.
Government and NATS Response
The UK Government branded the disruption “completely unacceptable.” A spokesperson for Prime Minister Andy Burnham confirmed confidence in NATS CEO Martin Rolfe, who has been instructed to carry out a full internal investigation. Rolfe is expected to deliver a report within one week on the root cause of the failure.
Transport Minister Heidi Alexander ordered the UK Civil Aviation Authority (CAA)
to conduct an independent review. She emphasized that passengers should not have to endure such disruptions and tasked the CAA with establishing the cause and recommending improvements to prevent future outages.
A NATS spokeswoman affirmed the company would conduct a comprehensive investigation to identify the root cause and determine any necessary further actions.
Technical Background and Corporate Details
The outage on September 8 and 9 stemmed from a technical fault in NATS’s flight data system, distinct from the 2023 failure caused by a rogue flight plan. This current incident contrasts with previous disruptions, including the August 2023 shutdown and a radar-related technical issue in July
2025 affecting Heathrow.
NATS, a public-private partnership partly owned by airlines such as British Airways and easyJet, paid £175 million in dividends to its owners in 2025. Ryanair, which has ongoing legal action against NATS over the 2023 outage seeking over £7 million in damages, has called for reinvestment of these profits into system performance and increased staffing.
Effects on Passengers and Airport Operations
The cancellations and delays led to displaced aircraft and crew across Europe, potentially disrupting onward flight connections beyond the immediate outage period. Heathrow Airport warned of ongoing knock-on impacts related to crew and aircraft repositioning.
Passengers traveling through impacted UK airports on
September 8 and 9 experienced significant schedule alterations due to the groundings, with major airlines cancelling or diverting hundreds of flights during this period.
