I agree with the previous posters search the threads here. I would also look through the nomination forum.
The fact is it can be all over the place. Anywhere from the traditional why USAFA to what do you do on your free time when you are with friends, and then, with everything possible in between.
Somebody could be asked why USAFA during their interview and they may say that their grandfather served in the AF in Intel during Vietnam. The next interview question could possibly be: Do you believe we should have been in Vietnam, or maybe even how do you think you would handle our society treating you like they did to our returning Vietnam Vets?
Now, you walk in next and are asked the same question, and your answer is since I was 6 I wanted to be an AF fighter pilot after visiting an airshow. The follow up is going to be totally different. Probably the What if you don't get pilot, what would you want to do in the AF?
It can become free flowing depending on the question and answer.
The best way impo to prepare for the interview is what my DS did. He made sure to wear his blazer /shirt/tie the night before, so he was comfortable wearing it during the interview. Shoes were polished too. During the 4 hr car ride he put in his headphones and listened to music. We did not pepper him with questions, EVER, be it prior to the day or on the ride.
~ We only said this to him: They are not your enemy, they know you are young and will be nervous. Chances are they will have kids your own age, and if not they have met a ton of nervous kids over the course of years doing the interviews. If you get that as a fact, you will do fine.
He must have done well because the interview was on Sat. and he got the congrats letter on Tuesday.
My other suggestion is ask the folks to have their friends over for dinner or a social hour. Have them interview you somewhere along the night (do not dress up for it). They will probably pepper you with questions, starting with the:
~ Why USAFA, why not USNA or USMA
~ What do you want to do in the AF
~ What if you don't get that career field?
It will be a committee, just like that dinner party, and as I said earlier, depending on how you answer one of the questions, the next follow up could change. Just like, if the folks did 2 dinner parties in a row with different guests. The 2nd one could just accept the why USAFA and move on to what do you want to do, and now follow up there.
If you hang with friends after school, than ask them what they think about you going to USAFA. They probably will have their own opinions.
~ Bud, are you really ready to give 9 years of your life (4 at USAFA and 5 AD)?