He said the experiment, which will allow passengers to gamble on games such as poker and blackjack as well as play arcade games, will come around 12 months after the carrier trials on-board mobile phone use next spring.
Talks are underway with the major mobile phone networks and potential gambling partners. A gambling product on the airline's website is expected to be introduced within the next couple of months.
Last April Ryanair abandoned its first experiment in paid-for in-flight entertainment involving Hollywood films and kids' cartoons after passengers showed reluctance to pay for what had once been a free service.
O'Leary said the decision to trial in-flight gambling using portable consoles follows the phenomenal success of its scratch card offer. Ryanair does not need a licence for in-flight gambling as it won't come under any national authority. It will be tax free.
The airline is looking for 25-30 pct of passengers to gamble and an average spend of 3-5 stg per passenger. This would add 50 mln stg to Ryanair's bottom line.
"You just don't know how far you can go with gambling revenue, it could be enormous," said O'Leary. "Ancillary revenue if gambling worked would become the biggest contributor to [total] revenue."
He dismissed the suggestion that the roll-out of gambling might discourage families from flying Ryanair.
"We recognise your right to object, but good luck, somebody else will have your seat," he said. The airline wanted to "blow up the bullshit notion that international air travel is [currently] some orgasmic trip".
O'Leary was speaking after the airline launched a 2 mln "free" seat sale, representing some 25 pct of available seats over the next three months.
"These free seat sales work," he insisted. "It is ultimately that which is going to widen the pricing gap between us and the flag carriers."
He said the logical extension of Ryanair's business model would see over 50 pct of its flights given away in the future.
O'Leary made his now customary attack on airports operator BAA PLC, labelling it an "out of control, inefficient airport monopoly", and the Civil Aviation Authority, branding it "clueless and aimless".
And, as usual, the environment lobby did not escape his wrath.
"These are the same passengers who flew with Ryanair to protest at the G8 summit [in Edinburgh]," he said.
"The best thing we can do with some of these environmentalists is take them out and shoot them... These head bangers want to preserve air travel for the rich people."
The airline will report second-quarter results on Nov 7.
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