Fred,
The application is pretty intense as this is a military scholarship and you have to fill out MANY forms just like anyone else who is going into the armed forces. There is not really an essay of sorts; just a short paragraph about why you want/feel you deserve the scholarship and why you want to be in the Navy. Also, not only do you have to be accepted based on you academic prowess but you must also be cleared physically. This means going through the Navy physical required for anyone joining. Mine was okay, although I was put in a group that consisted of mainly 17-18 year old recruits. It was a long day but I would have to say it was worth it. Just watch out for that rectal exam!!! WOW!!!!
As far as deadlines go, I am not really sure when they stop taking apps. I know that I am getting mine fairly early in the cycle. When I asked about a month ago how many scholarships were still available, my recruiter said that the Navy had given out about 50 scholarships so far. Since they only are giving out 350 this year, it is fairly competitive and, like anything else, the earlier you get your app in, the better off you will be. If you have any other questions, please feel free to ask. I will do my best to answer them. Take care... and GO NAVY!!!!!