UK airports warned of further disruption on Wednesday after a software failure in the country’s air traffic control system grounded more than 1,000 flights and left tens of thousands of passengers stranded.
Flights resumed at the UK’s busiest airports after Tuesday’s outage, but airlines faced widespread knock-on delays as aircraft and crew were repositioned, according to the Financial Times.
Heathrow, the UK’s largest airport, said its operations were “recovering” but warned passengers to expect delays as airlines worked to restore their schedules.
“Flights are operating today, but we are expecting knock-on impacts as aircraft and crew reposition,” Heathrow said.
Gatwick, the UK’s second-busiest airport, said flights had restarted but cautioned that it would “take time for our operations to fully return to normal”.
More than 100 flights had been cancelled by Wednesday, according to Flightradar24, with most due to depart from Heathrow.
The disruption on Tuesday forced incoming aircraft to divert and left thousands of passengers stranded after the failure prevented flights from taking off and landing at some of the country’s busiest airports.
Martin Rolfe, Chief Executive of the National Air Traffic Services (Nats), said the organisation had ruled out a cyber attack and would conduct a “very, very thorough investigation” into the cause of the failure.
The incident follows other disruptions involving the UK’s air traffic control system. A radar problem at Nats last year grounded hundreds of flights, while a separate software failure in 2023 caused widespread disruption at Gatwick during the peak summer season.
Rolfe said Tuesday’s failure was different from the 2023 incident, telling the BBC: “This will be something different we have never seen before in 50 years.”
Airlines criticised Nats over the latest disruption. Wizz Air described the organisation as “not fit for purpose”, while Ryanair, Europe’s largest low-cost carrier, called for Rolfe to be dismissed.
Nats manages the UK’s air traffic control system and is funded by airlines and the government.
Asked by the BBC on Tuesday whether he would resign, Rolfe said his immediate priority was resolving the disruption.
“I’m obviously focusing on making sure that we get this solved,” he said.
“My focus today has been making sure the team’s in the right place, we have the right resources, the technical issues are being investigated, and the recovery happens.
“There’ll be lots of time for that later, but that’s not now.”
