The writing sample is half a page, but you can use more. They will send you the paper to do that on, and your application, drug use certificate, medical exam information, ect. All that information will be in the booklet, also. You'll sit in a room with other cadets who are waiting to be interviewed. Then you will go, sit down, be interviewed, and leave.
Length depends on how many people are there, business, ect.
Email me with any more questions you may have. I realize that perhaps you don't allow her to post things online, I'm just saying this so that in case you didn't realize how much of a difference it makes, I'm telling you. The interview date is whenever you make it. This will contain all of this information. There are 3 essay questions, and they are picked by the Academy.