A further 60 flights from London Gatwick had to be cancelled on Wednesday evening due to a shortage of air traffic controllers, it has emerged.

Worst-affected was easyJet, with 42 cancellations.

Some 9,000 passengers were grounded when temporary air traffic control restrictions were put in place on Wednesday due to ‘short notice staff sickness’.

Other airlines affected included Iberia Express, Lufthansa, Norwegian and Vueling.

The cancellations follow days of chaos after the UK’s air traffic control system, managed by NATS, shutdown for four hours on Bank Holiday Monday.

NATS, which took over the provision of ATC services at Gatwick last October, said it has recruited more controllers ‘to safely oversee the 900 flights a day’ at the airport, but it will take up to a year for them to be trained to work in the Gatwick tower.

“Even a qualified controller will take up to a year to complete the specific training required,” said a spokesperson. “In the meantime, we are working closely with the airport and the airlines to deliver the best possible level of safe and efficient service.”

NATS said it has taken on 17% more controllers at Gatwick since summer 2022, but added: “ATCOs train in our college for six months to get their initial qualification and then a further year at the relevant airport to gain the required validation.”

The spokesperson admitted it will ‘take some time’ to increase the levels of staffing resilience in the tower to the target levels agreed with Gatwick when NATS took over the service.

“Until it is complete, issues such as short notice sickness can occasionally lead to periods of air traffic flow restrictions at the airport to allow the ATCOs to safely manage flights,” they added.

“In most instances, this does not lead to flight cancellations, such as those that unfortunately occurred at London Gatwick on Wednesday.

“We expect further resilience to be in place ahead of next summer.”