It's known for its no-frills service, £1 toilet charge, and less-than-friendly welcome at check-in. Now we know why.
Ryanair has been accused of "ruthlessly" exploiting its staff and profiting on the back of their poor treatment, after a former cabin stewardess blew the whistle on Europe's biggest budget carrier in a letter to her MP.
Sophie Growcoot said the carrier forced her to take three months' unpaid leave a year - in winter - during which she was not allowed to take another job.
Labour's Luciana Berger raised the matter in the Commons, telling MPs: "This is exploitation by Ryanair - pure and simple."
But Ryanair remained unrepentant, saying it was surprised at Berger's "false statements".
Growcoot, 20, revealed that under her employment contract with Ryanair contractor Crewlink, she was only paid for the hours when she was airborne, meaning she was not paid for pre-flight briefings, turnaround time between flights, sales meetings and time on the ground due to delays and cancellations.
The hourly flying rate was £13.07 an hour, with no contractual review for three years. The airline only paid her for four days' work a week, despite expecting her to be on call at an hour's notice on the fifth.
Standby days were unpaid unless she was called in. She was also made to pay £1,800 out of her own pocket to take a mandatory safety course, and a further £360 for a Ryanair uniform.
Growcoot's contract also made her laible for a €170 administration fee if she left her job within the first 15 months of employment.
Last year, Ryanair made record profits of almost £500m.
Growcoot, from Liverpool, told the Independent that on one occasion she was called in at 4am for a flight from Liverpool to Dublin, and paid £10 for a taxi to the airport. When she arrived, the flight was cancelled , and she was sent home without payment or even an apology.
Raising the issue in the House of Commons, Berger accused Ryanair boss Michael O'Leary, of "profiting on the backs of exploited cabin crew".
"This is exploitation by Ryanair - pure and simple," said Berger. "It's outrageous that an airline that reported record profits last year doesn't pay its staff for all the time they are at work. How can Michael O'Leary think it is fair or acceptable for his company to be profiting on the backs of exploited cabin crew like Sophie?"
Growcoot said she was "lured" into signing her employment contract without being given the full details.
"I was really excited about joining Ryanair's cabin crew at first, but it was a total nightmare," she said. "I couldn't believe it when I learnt I wouldn't be paid for all the time I was working.
"We'd be paid only when the wheels were moving, so I didn't get a penny for turnaround between flights or the hours when flights were delayed or cancelled.
"The recruiters knew exactly what they were doing. The charges kept getting bigger and bigger. I felt completely trapped."
Ryanair disputed Growcoot's claims.
A Ryanair spokesman said: "We are surprised by Ms Berger's statement in the House of Commons, since this person was not employed by Ryanair, but by a contractor company, Crewlink Ltd, and appears to have left their employment without notice after just two months.
"We are also surprised that Ms Berger made no effort to verify these false claims with Ryanair before using her House of Commons privilege to make false accusations."
Last year, a Ryanair ad campaign in which cabin crew were pictured in calendar girl poses under the banner "Red hot fares - and crew" was banned by the advertising standards authority for sexism.
Claims by the airline on Thursday that a flight from London Stansted to the Greek island of Kefalonia was diverted 200 miles away due to darkness were dismissed by insurance experts, opening the way for passengers to claim compansation.