NEW YORK ( TheStreet) -TheStreet Ratings' stock model upgraded Ryanair Holdings Plc ( RYAAY) to 'Buy' from 'Hold'. Ryanair was one of three airlines to be upgraded today. TheStreet Ratings released rating changes on 19 additional U.S. common stocks for July 21, 2010. In total, eight stocks were downgraded and 12 stocks have been upgraded by our stock model. Also lifting off the runway were AirTran Holdings ( AAI) and UAL Corp ( UAUA). Both of these airline stocks were upgraded to 'Hold' from 'Sell'. Airlines are doing a better job filling all available seats as over-capacity has been squeezed out of the system. Airline customers have now gotten used to being hit with extra charges that add to airline revenue. On my recent Chicago trip on AirTran I not only paid to check-in my suitcase, but also paid extra to select my window seats when initially purchasing my ticket. Ryanair is pushing the boundary of customer tolerance in attempting to get the U.S. Federal Aviation Administration to allow the company to modify its fleet of U.S. made Boeing ( BA) airplanes to charge passengers to use the bathroom. Ryanair believes that by charging for this service they can train passengers to use the terminal bathrooms before take-off so they can remove most bathrooms and add seats. -- Reported by Kevin Baker in Jupiter, Fla. For additional Investment Research check out our Ratings Research Center.