Flybe has blamed a shortage of pilots as one of the reasons after it cancelled dozens of flights today.
The UK regional airline said a "combination of factors" caused the disruption today.
Passengers travelling to and from Aberdeen, Belfast, Birmingham, Cardiff, London Southend and Southampton were among those whose travel plans were thrown into disarray.
The Exeter-based carrier said in a statement: "Flybe sincerely apologises to all our customers and partners affected by the current flight cancellations.
"Whilst 95% of Flybe flights are operating as per normal, we do recognise the impact of today's cancellations," the airline said.
"We are doing our best to mitigate the impact of the current situation that has arisen due to a combination of factors including seasonality, pilots' end of leave year, Easter holidays, base restructuring and the shortage of pilots across the industry that Flybe has highlighted over recent months."
Pilots' union Balpa said it has learned that Flybe is to close its bases at Cardiff and Doncaster Sheffield, and scale back its operations at Exeter.
Flybe flies 8.5 million passengers each year to 170 European destinations.
In February the airline was bought by a consortium led by Virgin Atlantic following poor financial results.
Connect Airways, which consists of Virgin Atlantic, Stobart Group and Cyrus Capital, paid £2.8m for Flybe's assets and operations.