The knock-on effect of a technical issue which hit air traffic control systems in the UK on Monday has continued into its third day.
National Air Traffic Services (NATS) suffered what it described as a “technical issue” preventing it from automatically processing flight plans.
This resulted in flights to and from UK airports being restricted while the plans were checked manually.
NATS said at 3.15pm on Monday the problem was resolved, but disruption continued into Wednesday.
Passengers stuck in Scotland have described their frustrations with being unable to reach their destinations.
One person from Cairo told STV News: “I left my home back in Cairo at 3pm Cairo time. The flight got delayed with three hours plus, and then I missed my connecting flight from Heathrow to Glasgow.
“I got a hotel, but still, like, it didn’t help because I arrived very late and I just got three hours of sleep.”
Another couple said: “Yesterday we stayed here. We were able to get a hotel a couple of miles away and yesterday we went to Paisley on the bus. We’d never been there before. A nice lunch.”
One man, who has been unable to get home to Manchester to his children said: “They told us that the next flight would be Saturday, so it’s obviously going to be another full week in Ibiza which with work and everything else is going on, it’s impossible to do.
“The idea was to just try and get into the UK and at least that way then I’ve got options available to get myself back to Manchester.
“It’s only part one of the journey. I’ve got the other part now, which again is not ideal and it’s going to be another night that I don’t see my kids.”
NATS confirmed on Tuesday that the air traffic control failure which led to a spate of flight cancellations was caused by flight data received, with both primary and back-up systems responding by suspending automatic processing.
NATS chief executive Martin Rolfe said systems have been running normally since Monday afternoon to support airline and airport operations.