Flights are grounded due to a technical issue with UK air traffic control

Britain National Air Traffic Service NATS said in a statement Monday afternoon that it had “identified and remedied” an information technology issue that affected automated flight planning across the country, including at London’s Heathrow Airport, one of the world’s busiest international airports.

NATS said it never closed UK airspace, but applied “traffic flow restrictions” while air traffic controllers had to revert to manual systems for the sequence of aircraft departures and landings.

“We are now working closely with airlines and airports to manage affected flights as efficiently as possible. Our engineers will carefully monitor system performance when we return to normal operations,” Nats said.

About 3,000 flights were scheduled to arrive in the country on Monday, and another 3,000 flights were scheduled to depart.

Paul Charles, an aviation expert, said: “Any malfunction affecting nearly a million passengers is a serious problem. These systems must not break down, especially on one of the busiest days of the year.”

“It’s symbolic of our broader IT infrastructure, which is colliding at the seams,” he said, suggesting there was a lack of investment during the coronavirus pandemic, when travel slowed.

The impact on Monday went far beyond Britain. European air watchdog Eurocontrol warned of “extremely significant” delays because Britain was suffering from a “failure in the flight data processing system”. AirNav Ireland, the Irish air traffic control company, said in a statement that there had been “significant delays to flights across Europe traveling to, from or through UK airspace”.

Passengers caught in the chaos shared their experiences.

On Monday morning, Washington Post reporter Jennifer Hassan boarded an EasyJet flight in Inverness, Scotland, bound for London’s Luton Airport. But after nearly two hours on the runway, passengers were asked to deplane and told to expect a delay of six to seven hours.

Sky News Producer Georgia Ziebart said her flight – from Palma, Mallorca to London Gatwick – was told that all planes in the air when the regime fell had been diverted to other countries.