These were the names we commonly used at sea;
CO - Boss, skipper
Executive Officer - X
Navigating Officer - Nav
4th Officer - 4th
Ships technical Officer - Charge
Second Engineer - Second
Leading Seaman Engineer - Killick Stoker - called by their Nickname
Leading Seaman Shipwright - Killick Chppie - Called by their nickname
Leading Seaman Electrician - Killick Greenie - Called by their nickname
Petty Officer Seaman - Buffer
Petty Officer Coxswain - Swain
Able seaman - Dibbies (AKA Dib dabs)
Cook - Cheffo
Radio Operator - RO
On a minor war vessel, military protocol on calling each other by ranks or sir or chief etc was not really enforced. We were just too smaller a crew and had to live with each other too long and in close confines.
Other names;
Doris Day
Head on a Stick
Tug Wilson (My 20 year nickname)
Timber Mills
I had a friend of mine with the surname Muston, so he went through his navy time as "Herman" (Herman Munster)
The original series of Patrol Boat was shot on an "Attack" class patrol boat and the Later series on a Fremantle class patrol boat.
Cheers
John W.