The
pennant numbers (a kind of
registration number, also known as
hull numbers) of
US Navy vessels carry a prefix of 2-4 letters designating the class of the ship; this practice dates back to the closing decades of the 19th century. These codes are fairly frequently used and recognised as a shorthand for that ship class (of any nationality). Those of more than 3 letters are usually a general class with a couple of extra letters to indicate weaponry (-G =
guided missile-armed) or propulsion (-N =
nuclear-powered) The following list is not yet exhaustive. Some classes are obsolete; many vessels have been reclassified as they were withdrawn to supporting roles in the later stages of their working lives.
- CV - Aircraft carrier
- CVL - Light aircraft carrier
- CVE - Escort carrier
- CVN - Nuclear powered aircraft carrier
- CVS - Anti-submarine warfare support carrier
- CVHE - Helicopter escort carrier
- BB - Battleship
- BC - Battlecruiser (never used for a completed USN vessel)
- SS - Submarine
- SSN - Nuclear powered (attack) submarine
- SSBN - Nuclear powered ballistic missile submarine
- CA - Heavy cruiser (formerly Armored cruiser; pre-1900 cruisers were just given C numbers but were later reassigned as CA)
- CB - "Large cruiser", USS Alaska class only
- CL - Light cruiser (pre-1900, Protected cruiser)
- CG, CLG - Guided missile cruiser
- DD - Destroyer
- DDE - Escort destroyer
- DDG - Guided missile destroyer
- FF, FFG - Frigate
- PC, PHM, PCE, PCG, PF, PG, PGG, PGH, PT - Coastal Patrol Craft
- AO - Oiler (A- prefizes for all auxiliary vessels)
- LST - Tank landing ship (L- prefixes for amphibious warfare vessels)
- MS - Minesweeper
- MCM - Mine counterneasures vessel (M- prefixes for all mine warfare vessels)
The numeric portion (only) of the pennant number is shown on the ship's side in peacetime colour schemes. You're expected to be able to work out what sort it is by looking at it ...