Hey FD
That's a real bummer for you.
I guess the best piece of advice I can give you is not to take it too personally.
Just because you didn't get the job doesn't mean you can't do it or you wouldn't be good at it. It just means that on the day, you perhaps didn't demonstrate your skills to the recruiters as well as someone else did.
I usually take those experiences as a learning opportunity and have a think about what I would have done differently for next time. I find it really useful to jot down some notes about the interview, what I did, look at what I know I didn't do well and save them for next time.
But remember, it's not personal! It's just on the day, someone else just performed a little bit better and you just have to show them your best next time!
Who was the airline if I can ask?