Mapped: Travel chaos as a UK air traffic meltdown grounds thousands of flights worldwide

A technical issue caused major travel chaos across the UK on Tuesday, grounding over 2,000 flights worldwide. London Heathrow Airport, one of the world's busiest hubs, was the worst affected. NATS, the country's air traffic control provider, suffered the outage in the afternoon. Many airplanes and flight crews were left stranded in unexpected cities, causing further disruption.

British Airways reported that 190 of its flights still had to be canceled on Wednesday morning. Cirium data shows that 1,746 flights to and from the UK were canceled or did not depart on Tuesday, accounting for about 30% of the day's schedule. Heathrow had a cancellation rate of nearly 50% on Tuesday, with more than 700 flights in and out of the airport canceled as of Wednesday lunchtime.

Diverted flights included 70 bound for Heathrow and six Airbus A380 flights operated by Emirates. The disruption is the latest in a series of recent issues with NATS, including a software failure in August 2023 that affected 700,000 travelers and was estimated to have cost up to £100 million. NATS has apologized for the latest disruption and stated that it will take time to fully recover from the current situation.