Planning and writing a sci.fi story with Space Navies(tm), and I realize that I'm tempted to wonder why you need more than three of four people punching buttons and pulling joysticks to move a ship and fire the weapons.
So, obviously there are more roles to fill, I realize (and of course you gotta consider shifts, crews obviously need to sleep but you can't just shut down your ship while everyone sleeps), but I have no notion of exactly how many people fill which roles - Engineering? Navigation? Weapons control? Guards? Making food?
Are there any lists or overviews over what various contemporary naval vessels' crews are composed of? That is, not just the number of crew but also an approximate distribution of how many fill what roles on a ship - or for that matter, what roles you actually need on ships. Even if it wouldn't be fully translatable to space navies I can extrapolate well enough I think.