RYANAIR boss Michael O'Leary has hit back at criticism of the airline's raunchy cabin crew calendar by sending it to an MP.

Mr O'Leary posted the 2010 Ryanair Cabin Crew Charity Calendar to "anti-fun" Labour MEP Mary Honeyball after she accused Ryanair of "forcing" cabin crew to take part in the calendar, the Daily Mail reports.

The calendar, which hopes to raise money for the UK KIDS charity, shows some cabin crew topless and others stripped down to a bikini.

But Mr O'Leary insists staff volunteered to do the shoot.

"Ryanair's cabin crew volunteer to take part and this year over 800 of the airline's 4000 cabin crew applied for this great charity event," Mr O'Leary said.

Reports say Mr O'Leary has already bought the first 100 copies of the calendar.

Proceeds of the 2010 calendar will bring the total raised by Ryanair's stripped-down cabin crew to almost £300,000 ($A534,000) since the first calendar was published in 2008.

"This year's calendar is the hottest yet and we hope to raise £100,000 ($A178,000) to help KIDS assist even more disabled children and their families in the UK," Ryanair spokesman Stephen McNamara said.

"Those who want to help KIDS and bring a smile to someone's face all year long should buy the calendar onboard Ryanair flights or from the Ryanair website today."

Source: News.com.au