You also have to remember that meeting the qualifications does not guarantee you a job. There are a LOT of good people out of work right now. There was item on CNN.com yesterday about a woman who had been making over $100,000/yr applying for a $7/hr job at a new discount store.
So, expect that there are going to be a number of applicants besides you that
qualify for the job. One of them may be picked over you for reasons that have nothing to do with qualifications, or the reverse may be true. You are picked over another person who is equally qualified.
Hiring new employees is not an exact science. Sometimes it comes down to the interviewer's gut feeling that this person would make a better employee than that person. This sort of situation happens a lot when there are a lot of people out of work and the available pool of applicants is large.
Airline hiring tends to attract a lot of applicants because they think that working for an airline is a glamorous job, and they will be able to fly all over the world on vacation. And, you can if you are willing to make that trip to Russia in the middle of the winter, and to the desert in high summer--i.e., the off season.
One suggestion: if you don't get the job this time, find out how to write to the person who interviewed you. Write them a thank you note thanking them for the opportunity to interview with the airline. Tell them that though you are disappointed that you were not selected, you look forward to the opportunity to apply again in the future.
Persistence pays in some jobs, and I promise you if you do this they will remember you.