327 flights were cancelled on Wednesday
More than 2,000 flights have now been cancelled after a technical problem at UK air traffic control provider NATS caused widespread disruption.
Tens of thousands of passengers have been affected by the disruption across the UK and beyond.
According to aviation analytics firm Cirium, 327 flights were cancelled on Wednesday, following around 1,750 cancellations on Tuesday.
NATS said its flight data processing system experienced a technical problem, affecting flights across the country’s aviation network.
NATS chief executive Martin Rolfe apologised to passengers and admitted that resolving the issue had taken longer than expected.
He said the organisation would conduct a full investigation into the incident.
The technical problem was not believed to be connected to the system failure that caused widespread disruption in 2023.
Heathrow, Gatwick, Manchester and Birmingham were among the airports experiencing significant disruption.
Heathrow initially suspended flights around lunchtime on Tuesday before traffic resumed, although further disruption followed later that afternoon.
The airport said its operations were recovering on Wednesday, but warned passengers about continuing knock-on effects.
A Heathrow spokesperson said flights were operating, but aircraft and crew would need to be repositioned.
Gatwick also confirmed that flights had resumed but warned that it would take time for operations to fully return to normal.
Manchester, Luton, Stansted, Bristol and Belfast City airports also reported that flights had resumed.
However, several airports warned passengers that delays and cancellations could continue because of the backlog.
Even after NATS resolved the technical problem, airlines faced difficulties because aircraft and crew were left in different locations.
The disruption also affected airports in Ireland, highlighting the wider impact of the UK air traffic control problem.
Passengers have been advised to check their flight status directly with their airline before travelling to the airport.
Heathrow has told passengers to only travel if their flight has been confirmed as operating.
The latest incident has renewed criticism of NATS and concerns about the reliability of Britain’s air traffic control system.
It is the third significant technical issue involving NATS in recent years.
In 2023, a computer shutdown during the August bank holiday caused widespread disruption and affected around 700,000 passengers.
A smaller NATS outage in 2025 resulted in around 150 cancellations.
Airlines including Ryanair and Wizz Air have called for changes to the organisation following the latest disruption.
Wizz Air UK managing director Yvonne Moynihan questioned whether Martin Rolfe should remain in his position.
She said repeated failures should raise questions about the leadership of the organisation.
Rolfe was paid £1.4 million for the year ending March 31, including a £343,000 bonus.
The NATS chief said his immediate focus remained on resolving the current disruption rather than discussing his future.
Downing Street said Rolfe continued to have the confidence of the Government.
However, Foreign Secretary Ed Miliband described the outage as unacceptable.
The Government is expected to face further questions about investment and safeguards within Britain’s air traffic control system.
For passengers, the immediate priority remains reaching their destinations as airlines work through the backlog.
Travellers should continue checking directly with their airlines for updates as disruption is expected to continue over the coming days.
