Software glitch caused travel chaos, says air traffic control body
Software glitch caused travel chaos, says air traffic control body. Image source, Getty ImagesImage caption, Thousands of passengers were delayed by the NATS outageByKaty Austin, Transport correspondent, Tom Espiner and Simon Browning, Business reportersPublished18 September 2026, 13:40 BSTUpdated 1 hour agoAn air traffic control failure that sparked widespread travel chaos earlier this month was caused by a "software defect" affecting the system underpinning UK air space management, the national air traffic service Nats has said.
What happened
In an initial report, external, Nats said the software defect meant air traffic controllers had reduced information available, so restrictions were put in place to limit air traffic to maintain safety. One of those solutions appears to be an $875 million AI software program that is expected to help air traffic controllers manage their workflows and more safely navigate flight routes. "It's clear we need to urgently understand why this issue was not discovered and fixed before it caused chaos," Alexander said, adding that a Civil Aviation Authority review was underway.
In 2023, a computer shutdown over the August bank holiday weekend caused chaos for 700,000 passengers. Tim Alderslade, chief executive of Airlines UK, said: "Once again, it is passengers who have suffered and airlines who have picked up the pieces – and the tab – of an ATC [Air Traffic Control] system failure, while Nats itself faces no real consequences. Get in touchWere you affected by this air traffic control failure? 25% off tickets now Back by popular demand: Save up to $300 on Disrupt Close In Brief Posted: 3:14 PM PDT · September 17, 2026 Image Credits:Archer Aviation Lucas Ropek The FAA’s plan to fix air traffic? $875M worth of AI The Federal Aviation Administration has been struggling to manage an air traffic control shortage throughout the country.
The wider picture
The Wall Street Journal reports that the FAA will soon launch SMART, which stands for Strategic Management of Airspace, Routes, and Trajectories — an automated software program designed to help streamline air traffic operations. Topics AI, air traffic control, Government & Policy, In Brief October 13 – 15 San Francisco Last day to book an exhibit table is September 18. Nats chief executive Martin Rolfe told the BBC he would not resign, saying the software defect was "very, very obscure. Transport Secretary Heidi Alexander called the disruption "completely unacceptable", while industry body Airlines UK is writing to Nats to demand immediate compensation for costs incurred.
This is the third national air traffic incident in the past three years. There was another, smaller Nats outage in 2025, which caused 150 cancellations. Addie questioned the rules around compensation, saying there had been multiple air traffic outages. Contact formContact formRelated topicsLondon Heathrow AirportTravel
What has been reported
A one-page readout on the program describes SMART as “a cloud-based platform system that enhances existing FAA air traffic management systems. ” It adds that the program uses AI to assess “airline schedules, weather, airport capacity, airspace conditions, and operational constraints to predict traffic flows and identify potential conflicts before they occur. ” SMART, the product of a firm called Air Space Intelligence, will cost the government that amount over a 12-year period, the outlet writes. The software will roll out in the Washington, D.
C. , metropolitan area first before expanding to other regions, it says. Earlier this year, the FAA also announced a “bold, new” hiring plan that the agency said would “erase the longstanding staffing shortage,” and the government is separately engaged in a broad effort to modernize the nation’s aging air traffic systems. BOOK NOW Newsletters See More Subscribe for the industry’s biggest tech news Related AI Is the AI safety debate about safety or control?
The failure led to more than 2,000 flights being cancelled and hundreds of thousands of passengers affected. The problem happened "in the space of a millisecond", Nats said, leading to the system producing corrupted data. ""You can fly to almost anywhere from almost any airport at almost any time.
What happens next
If that stops, even for a moment, then you get huge disruption. "My job is to make sure that we have this happen as infrequently as possible," he added. The incident prompted questions over the resilience of Nats' systems, and some airlines questioned the position of Mr Rolfe. There has also been anger from passengers about how much support they got from airlines, and about the fact that they are unlikely to be entitled to compensation because the regulator judges the situation was extraordinary circumstances.
The defect occurred at 10:00am on 8 September, but it did not become apparent this was a serious problem for another two and a half hours. The system restart did not start until just after 3:15pm, and restrictions on UK airspace were not lifted until 7:30pm. Flights in and out of the UK's main airports were affected, including Heathrow, Gatwick, Luton and Glasgow.
The report has been compiled by The Daily Waves using information reported across bbc.co.uk, techcrunch.com. Details are presented according to the information available at the time of publication and may change as authorities, organisers or other relevant parties provide updates.