Give up on nav mesh. It is not appropriate for this usage; it really only works with static geometry.
The only way I could see to make it work for something like this is if your battleship is fixed at 0,0,0 and you move everything else around it (which might be appropriate for some kinds of games).
Otherwise, if you like the nav mesh style, look for a third-party A* asset that does basically the same thing but works with dynamic or moving meshes at runtime.
I think it not work. it is good for physical control in unity, but very bad for model texture It multiply the work load by up to 6. One texture increase to six texture.