British Airways computer systems went down globally on Saturday causing major delays for holiday makers at the start of the bank holiday weekend.
It came as many Britons headed overseas for the long weekend and half-term school holidays.
The carrier apologised for the "global system outage" and said it was "working to resolve the problem as quickly as possible", the Guardian reported.
BA's website was unavailable and some travellers claimed they could not check in on the mobile app, with many venting their frustration on the social media.
Others said they had been delayed at the airport or on runways before take-off.
There were reports that hundreds of bags were left unattended as BA staff tried to control the situation.
One passenger tweeted: "Stuck on a British Airways plane at Belfast, going nowhere. 'BA computers down worldwide', whatever that means!"
Another posted: "British airways computers down T5 and standstill, stranded on the plane and they make us pay for food!! Please retweet this indicency!"
A passenger claimed that BA "made no announcements at all" about the delays.
A spokeswoman for the airline confirmed the computer system outage and said: "We apologise to customers who are facing some delays following an IT outage this morning."
"We are working to resolve the problem as quickly as possible."
It came a day after passengers at Gatwick airport faced chaotic scenes and long queues due to a baggage system problem, said the report.
Those taking flights on Friday were forced to travel without their hold bags and were asked to carry any essential items in their hand luggage.
