Ryanair's chief executive has admitted the airline is in "a mess". It's cancelling up to 50 flights a day for the next six weeks, because of mistakes planning pilots' holidays.
Michael O'Leary says anyone affected is being kept informed, and that "we sincerely apologise and we are working very hard at the moment to finalise the list of flight cancellations".
Today alone, flights between Dublin and Brussels, Amsterdam, Manchester, London Gatwick, Bristol & Barcelona have been affected.
In a statement, Ryanair says it's "messed up" the planning of pilot holidays, and says the cancellations make up less than 2 percent of its schedule.
The issue with pilots' holidays has been well flagged, as the Irish Aviation Authority switches its calendar to European norms, but it's also emerged that Ryanair is losing pilots to competitors like Norwegian Air who recently hired 140 ex-Ryanair pilots.
The Commission for Aviation Regulation says if Ryanair cancels a flight, passengers are entitled to an alternative flight or a full refund.
As Ryanair's share price has dipped by 3 percent, aviation experts say the reputational damage to Ryanair will be severe. A full list of cancelled flights is available on Ryanair's website.