Class (ship)

A ship class is a group of ships of a similar design. This is distinct from a ship type, which might reflect a similarity of tonnage or intended use. For example, USS Carl Vinson is a nuclear aircraft carrier (ship type) of the Nimitz class (ship class).

In the course of building a class of ships, design changes might be implemented. In such a case, the ships of different design might not be considered of the same class; each variation would either be its own class, or a subclass of the original class (see County-class cruiser for an example). If ships are built of a class whose production had been discontinued, a similar distinction might be made.

Ships in a class often have names linked by a common factor: e.g. Trafalgar-class submarines' names all begin with T (Turbulent, Tireless, Torbay); and Ticonderoga-class cruisers are named after American battles (Yorktown, Bunker Hill, Gettysburg, Anzio). Ships of the same class may be referred to as sister ships.

The name of a naval ship class is most commonly the name of the lead ship, the first ship commissioned or built of its design. However, other systems can be used without confusion or conflict. A descriptive name may be used; for example it was decided to group destroyers made to the same design as HMS Tomahawk, all named after weapons, as the Weapon rather than Tomahawk class.

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