Air Force ROTC will guarentee a flight spot even before commiting. They did it to me, I turned it down because I got the recruiter to talk. He said that one other thing I could do to fly in the military is go to college on my own, get all my flight ratings, and then apply into the armed forces as a pilot. That way, if you're in, you're in as a pilot. If not, then you go on your way. Or, I could commit to ROTC and bust my butt at getting spot along with 400 other students get turned down, and be a weapons officer or something that does not involve flying. This was only for Air Force so I don't know much about the other branches.