Surely Captain?

( Dr Preference AjcuiVd289, Wed 27 Aug 2008, 10:36, archived)

That would be the best
but realistically (yes, I know) I'd take security officer.
( Captain Wow currently being a cunt in Infamous, Wed 27 Aug 2008, 10:37, archived)

Chief of Security might hold the rank of captain.
While the actual captain might be a commodore or something.
( Moon Girl Technologies horrendous beanbag, Wed 27 Aug 2008, 11:11, archived)