LONDON -(Dow Jones)- Ryanair Holdings PLC (RYA.LN), the airline, Tuesday in Paris signed a Memorandum of Understanding with Commercial Aircraft Corp. of China, or COMAC, to participate in discussions on the development of the COMAC C919 aircraft for Ryanair, which would be designed to carry up to 200 passengers and should be available from 2018 onwards. MAIN FACTS: -Ryanair will share its experience and expertise to assist COMAC to develop the new C919 commercial aircraft, with up to 200 seats, which would enable Ryanair to lower costs and continue to lower fares for its passengers across Europe. -Ryanair is pleased that there is now a real alternative to Boeing and Airbus. -Ryanair will have a fleet of over 300 Boeing aircraft by 2013 and remains in continuing discussions with both Boeing and now COMAC for a replacement aircraft order of at least 200 aircraft. -Shares at 0845 GMT up 2.41% at EUR3.15 valuing the company at EUR5.3 billion. -By Jana Weigand, Dow Jones Newswires; 44-20-7842-9314; jana.weigand@dowjones.com