There are a lot of posts that discuss this. But, to come up with a curt, consolidated reply: Yes, Yes, and Yes. Nukes can get "cut" for a lot of things. The program prides itself of excellence and anything short of that (although there's some debate to the interpretation of anything these days) can lead to being "cut." Things like not being physically fit, drug or alcohol problems, integrity issues, or just not being able to make it academically can lead to being dropped from the field. Just like most things, there is some give to this and a single exam failure won't get you removed. Odds are that if you are accepted into the program and you commit yourself to completing it you will make it through. There are so many resources available these days that it's near impossible not to finish it if you embrace the challenge. Enlisted and Officers alike. I had a bad run a few months ago with some of my officer students failing final watch boards. If you can't stand watch at a shore-based prototype there's no way you'll be able to do it at sea. If, however, you find yourself capable of upholding the NNPP values of Knowledge, Integrity, and Excellence then you can happily serve your 30 years in our country's nuclear navy. Assuming, of course, you don't meet high year tenure.