O’Leary said bars in airports should stop serving alcohol during early morning hours and urged authorities to introduce limits on the number of drinks passengers can buy before boarding.
He said: "It’s becoming a real challenge for all airlines. I fail to understand why anybody in airports bars is serving people at five or six o’clock in the morning. Who needs to be drinking beer at that time?"
Airside bars are currently exempt from normal pub licensing rules, allowing alcohol to be served throughout the day and night in many airports.
O’Leary argued the regulations should be brought more in line with standard pub opening hours.
He said: "There should be no alcohol served at airports outside [those] licensing hours. We have been calling for many years for a limit of two drinks per person per airport, why don’t you limit people by boarding pass?"
According to the Ryanair chief executive, disruptive incidents involving intoxicated passengers have risen sharply over the past decade. He claimed the airline is now forced to divert almost one flight every day because of passenger behaviour.
O’Leary said: "In the old days if somebody had drunk too much, they get on board, they fall asleep. You have a combination of drink and drugs — they want to fight somebody, they’re hyper. We and all the airlines are having enormous problems."
He added: "If I go back ten years we would have maybe one flight diversion per week, now I would say we are running close to one diversion a day."
The Ryanair boss also criticised airport bars for continuing to serve alcohol during delays.
He said: "We are reasonably responsible but the ones who are not responsible, the ones who are profiteering off it, are the airports who have these bars open at five or six o’clock in the morning and during delays are quite happy to send these people as much alcohol as they want because they know they’re going to export the problem to the airlines."
Under UK law, being drunk on board an aircraft is a criminal offence and passengers can face fines, prison sentences, airline bans and compensation costs if flights are diverted.
AirportsUK said the aviation industry already works together through the One Too Many campaign, which highlights penalties including fines of up to £5,000, airline bans and diversion costs that can exceed £80,000.
The organisation added: "We encourage everyone who flies to take personal responsibility for their actions, to behave with respect and courtesy to staff and other passengers, and to ensure they do not ruin their, and others, hard-earned holidays."
