Dear Mr. Offshore,
I think I’m going to get fired from my job. Is now the right time to tell my supervisor that he’s an idiot?
— offshore GOM
Not unless the emotional satisfaction you expect to get outweighs two outcomes; first, getting canned, and, second, having your old supervisor sabotage any new job.
My advice: You are a professional. Do your best work all the way to the end of the project. Then head back to the beach getting ready to take some time off, keeping your thoughts to yourself. If your sup really is an idiot, he will eventually be taken out by upper management after he trips over his own feet. Years from now you may end up on a job with him and you have no way out. This is a small industry and you never know where you’ll bump into him again.
Good luck and stay safe.