UK airports warned of further travel disruption on Wednesday following a software failure in the air traffic control system. The outage grounded over 1,000 flights on Tuesday, stranding tens of thousands of passengers. Heathrow, the country's busiest airport, reported operations were recovering but warned of ongoing delays as airlines reposition aircraft and crew.

Gatwick, the second-busiest airport, said flights had restarted but would take time to fully normalize. More than 100 flights were cancelled on Wednesday, mostly from Heathrow. Martin Rolfe of the National Air Traffic Service (NATS) ruled out a cyber attack, stating there would be a thorough investigation into the failure.

Last year's radar issue and a 2023 software failure caused prior chaos. Airlines including Ryanair and Wizz Air criticized NATS, with Ryanair calling for Rolfe's dismissal. NATS is funded by airlines and the government.