Naval Vessel Designators: Auxillaries, Submarines and Surface Warships.

[Ex-Dragoon]

Aircraft Carriers
CV -- Aircraft Carrier
CVA -- Attack Aircraft Carrier
CVAN -- Nuclear Powered Attack Aircraft Carrier
CVE -- Escort Aircraft Carrier
CVL -- Light Aircraft Carrier
CVN -- Nuclear Powered Aircraft Carrier
CVS -- ASW Aircraft Carrier

Surface Warships, Major
BB -- Battleship
BC -- Battlecruiser 
CA -- Heavy Cruiser
CG -- Guided Missile Cruiser
CGH-- Aviation Cruiser Guided Missile
CGN -- Nuclear Powered Guided Missile Cruiser
CL -- Light Cruiser
DD -- Destroyer
DDG -- Guided Missile Destroyer
DDH-- Aviation Destroyer
DE -- Destroyer Escort
FF -- Frigate
FFG -- Guided Missile Frigate
FFH-- Aviation Frigate

Submarines
SS -- Submarine
SSBN -- Nuclear Powered Ballistic Missile Submarine
SSG -- Guided Missile Submarine
SSGN -- Nuclear Powered Guided Missile Submarine(cruise missiles)
SSK -- Hunter-Killler Submarine
SSN -- Nuclear Powered Submarine

Amphibious/Landing Ships
LCC -- Amphibious Command Ship
LHA -- Amphibious Assault Ship (general purpose)
LHD -- Amphibious Assault Ship (multi purpose)
LKA -- Amphibious Cargo Ship
LPA -- Amphibious Personnel Transport
LPD -- Amphibious Transport Dock
LPH -- Amphibious Assault Helicopter Carrier
LSD -- Dock Landing Ship
LSL -- Landing Ship, Logistic (courtesy of whiskey601)
LST -- Tank Landing Ship

Mine Vessels
MCM -- Mine Countermeasures Ship
MCS -- Mine Countermeasures Support Ship
MF -- Fleet Minelayer
MHC -- Coastal Minehunter
MM - general mine warfare (MCDV's)[courtesy of navymich]
MSB -- Minesweeping Boat
MSC -- Coastal Minesweeper
MSO -- Ocean Minesweeper

Surface Warships, Minor
PC -- Coastal Patrol Craft
PG -- Patrol Gunboat
PGM -- Missile Patrol Boat
PHM -- Patrol Combatant, Hydrofoil
PT -- Torpedo Boat
PTF -- Fast Patrol Boat

Auxiliaries
AE -- Ammunition Ship
AF -- Refrigerated Stores Ship
AFS -- Combat Stores Ship
AG -- Miscellaneous Auxiliary
AGF -- Flagship
AGOR -- Oceanographic Research Ship
AGS -- Surveying Ship
AK -- Cargo Ship
AO -- Fleet Oiler
AOE -- Fast Combat Support Ship
AOR -- Replenishment Oiler
AR -- Repair Ship
ARS -- Salvage Ship
AS -- Submarine Tender
ATF -- Fleet Tug
AV -- Seaplane Tender
AVT -- Aircraft Transport

If you find any others I will add them, the only stipulation is they must be official designators.

 

[flyskyzxd]

Thank you！