During zero week, the Military Training Instructors (T.I.s) will explain what happens to those who are not quite "cutting it." Recruits are all given little forms (designed to keep in your breast pocket), affectionately known as "341s." If you goof up significantly, and your T.I. (or another T.I.) catches you at it, he/she will demand that you give him/her a 341. Getting too many 341s "pulled" can cause you to be recycled.
Process of Being Recycled During Training
Each day of training is counted as a specific day (day one, day two, day three, etc). Let's say you're not hacking it, and have had several 341s pulled by day 23 of training. Your squadron commander (on the recommendation of your T.I.) can "recycle you" by moving you to a flight who is on day 5 (or earlier) of training. This gives you a chance to "relearn" what you should have learned in the first place.
Being "recycled" is the ultimate threat, and T.I.s often use it as a means to keep everyone motivated ("I'll recycle you so far back, you'll be in your grandfather's flight!"). However, recycling is not as easy as the T.I. makes it seem. The T.I. has to document the behavior, show documentation that he/she tried to help the recruit change the behavior, convince his/her bosses that recycling is the best option, and then convince the squadron commander. One graduate of Air Force Basic Training puts it succinctly:
"Only people who get recycled (for disciplinary reasons) are the bonafide screw-ups. In our flight, we pretty much knew who would be leaving us rather quickly and that it was just matter of time. There was only one 'recyclee' that baffled our flight and even T.I. expressed minimal regret. I think that by mentioning this tidbit it instilled a little more confidence in people who are just coming in."
Many minor infractions are corrected on the spot by "dropping you" for pushups. The regulations restrict the number of pushups a T.I. can make a recruit do (15 for males, 5 for females), but you can be "dropped" up to five times, one-after-the-other. Additionally, if no one is watching, a T.I. might occasionally "fail" to hear your count, and you might wind up doing more than the "authorized" amounts. Another way that the T.I. can make this punishment seem worse than it seems is to do a "slow count," making you stay in the "down" position for a long time. In any case, it's wisest not to be a "barracks lawyer" and tell the T.I. he can't make you do that.
Those with serious attitude problems may receive an Article 15 (nonjudicial punishment) with the sentence of Correctional Custody (CC). If you think regular basic training is bad, try 30 days or so in CC. Every single second of your life is regimented. Your commander will probably tell you that CC is a privilege, however; as at least it means the Air Force has decided to try and keep you. After you've been "re-blued," you'll normally re-enter basic on the exact same "day" you left. In other words, if you entered CC on day 10 of training, you'll recycle to day 10 or so of training when you are released from CC.