UK airports are largely returning to normal after days of widespread disruption caused by an air traffic control system failure, but hundreds of thousands of affected passengers have been warned they are unlikely to receive compensation.
Around 2,163 flights were affected after National Air Traffic Services (NATS), the UK’s air traffic control provider, experienced a technical issue on Tuesday, 8 September. The four-hour outage led to widespread cancellations and delays, with disruption continuing into Wednesday as airlines worked to reposition aircraft and crews.
Operations had largely stabilised by Thursday evening. According to aviation analytics firm Cirium, 54 of 3,028 scheduled arrivals were cancelled or did not operate, equivalent to 1.78%, while 47 of 3,033 scheduled departures were affected, or 1.55%. Cirium said the figures were only slightly higher than on a normal day. Heathrow remained the most affected airport, with 23 arrivals and 12 departures cancelled.
Inside Heathrow airport as flight are closed because of a computer glitch.. pic.twitter.com/yYJDTbVqvI
— London & UK Street News (@CrimeLdn) September 9, 2026
The improvement follows two days of major disruption across airports including Heathrow, Gatwick, Manchester and Stansted. More than 330,000 passengers were affected overall, according to Airlines UK, while Heathrow and British Airways suffered the largest number of cancellations on Wednesday.
Despite the scale of the disruption, the UK Civil Aviation Authority (CAA) has warned that passengers whose flights were directly affected by the NATS failure are unlikely to qualify for compensation.
“We consider that disruption caused by the NATS outage is likely to be considered the result of ‘extraordinary circumstances’ under passenger rights rules,” the regulator said. “This means that although passengers should be looked after by airlines, they are unlikely to be entitled to compensation for delays or cancellations that were directly caused by the incident.”
Thousands of passengers have faced frustrating delays and cancellations, and we understand the anger this has caused.
— Department for Transport (@transportgovuk) September 9, 2026
The Transport Secretary @Heidi_Labour met with NATS leadership this morning to demand answers and requested a rapid review within one week. The UK’s independent… pic.twitter.com/YVD86U92Qq
However, airlines still have obligations towards affected travellers. Depending on the circumstances and length of the disruption, passengers may be entitled to assistance such as meals, refreshments and accommodation, as well as refunds or alternative transport when flights are cancelled.
The incident has increased pressure on NATS and its chief executive, Martin Rolfe, following three major system failures in three years, including incidents in August 2023 and July 2025. Rolfe has been given a week to provide information on the reasons behind the latest failure.
Transport Secretary Heidi Alexander has said she does “not believe this issue was unavoidable” and asked the CAA to conduct an independent review, which is expected to report within six months. NATS is also carrying out its own investigation, while Rolfe has said the incident was not caused by a cyber attack.
With flight schedules now close to normal, attention is shifting from the immediate disruption to the resilience of the UK’s air traffic control system and the financial consequences for airlines and passengers.
