Flights resumed at Liverpool John Lennon airport after operations were suspended on Monday afternoon due to a power failure.
Some inbound services had to be diverted to other airports, including Manchester and Birmingham, while others faced delays.
A series of flights due to depart from the airport were also held up during the afternoon.
Coaches were laid on to collect passengers whose flights had been diverted.
An initial statement from the Merseyside airport said: “Unfortunately, a power failure is impacting air traffic control and aircraft operations are temporarily suspended.
“Passengers, or those meeting flights, should contact their airline for the latest flight information.
“Engineers are working to resolve this as soon as possible, with updates to follow.”
The airport later issued a statement on X, formerly Twitter, saying: “Our engineers have resolved the earlier air traffic control power issue, and aircraft operations have now resumed.
“There may be delays to your flight, please consult your airline for any further updates.
“We apologise for any inconvenience caused.”