If you were being who you are (i.e being yourself) in the interview then the reason you were not picked is that they felt you were not a suitable as an Air Force Officer/Pilot candidate. You don't get to do something just because you want to.
And that's ok, because in my experience I have found that people who don't get accepted to do a certain thing, whatver it might be, would generally not have fit in to the thing they were trying to do had they been accepted. That's why organizations large and small have their respective screening processes.
Now if you never made it to the interview process, then obviously they had other applicants who were better qualified. So what you can do is find out who is getting accepted.