Thousands of airline passengers were hit by flight cancellations late on Wednesday night due to an air traffic control issue.
Analysis of flight data websites showed about 58 flights to or from Gatwick – the UK's second busiest airport – had been cancelled, affecting about 9,000 passengers.
The air traffic control problem comes a week after a technical glitch at several airports caused widespread chaos that stranded passengers for days.
Gatwick Airport said it was subjected to a restriction in the number of planes that could take off and land because of “short notice sickness” at its air traffic control tower.
EasyJet chief executive Johan Lundgren warned that passengers were “being let down once again” and claimed National Air Traffic Services’ staff shortages had caused disruption at Gatwick for a total of 29 days since May.
“An independent and wide-ranging review of Nats has never been more urgent,” he said.
The first flight affected by the disruption appeared to be an easyJet arrival from the Greek island of Zakynthos, which was diverted to Luton.
“Nats air traffic control staffing shortages at Gatwick led to a significantly reduced flow rate being imposed on airlines, meaning some flights were delayed and some were unable to operate,” easyJet said in a statement.
“While this was outside of our control, we are sorry for the inconvenience caused to our customers and did all possible to minimise the impact of the disruption, notifying those on cancelled flights of options to rebook or receive a refund and provided hotel accommodation and meals where required.”
Among the other airlines to cancel flights from Gatwick on Wednesday night were Lufthansa, Norwegian, Iberia Express and Vueling.
Affected passengers are not entitled to compensation as the disruption was outside of the airlines' control.
Nats, the company that supplies air traffic controllers in the UK, said it was “working in line” with a staffing plan agreed on with Gatwick bosses when it took over the provision of air traffic control services at the airport in October 2022, which includes training further staff.
“Due to short-notice sickness in the air traffic control tower, temporary air traffic control restrictions were put in place, resulting in some delays and cancellations by airlines,” a Gatwick Airport spokeswoman said.
“London Gatwick would like to apologise to any passengers who have been impacted by these restrictions. Please contact your airline for more information.”
A Nats spokesman said: “We are training new controllers to safely oversee the 900 aircraft per day that use Gatwick, the world's busiest and most complex single-runway airport.
“Even a qualified controller will take up to a year to complete the specific training required.
“In the meantime, we are working closely with the airport and airlines to deliver the best possible level of safe and efficient service.”
The Civil Aviation Authority announced on Wednesday that an independent review would be carried out into last week's air traffic control failure.