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, is a nuclear aircraft carrier of the Nimitz 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 (, ); and Ticonderoga-class cruisers are named after American battles (, , ).
Naval Ship Class naming conventions
The name of a ship class is most commonly the name of the first ship commissioned or built of its design. However, other systems can be used without confusion or conflict.
In the United States Navy
a class is always named after the lead ship
, that is, the first ship of the class to be approved by the United States Congress
. Due to numbering conventions the lead ship almost always has the lowest hull number
of her class.
Europe in general
In European navies a class is named after the first ship commissioned regardless of when she was ordered or laid down. In some cases this has resulted in different class names being used in European and U.S.
references; for example, European sources record the Colorado-class battleships
of the United States Navy
-class", as was commissioned before .
The British Royal Navy
has used several methods of naming classes. In addition to the accepted European convention, some classes have been named after a common theme in the included ships' names, e.g., Tribal class destroyers
, and some classes were implemented as an organizational tool, making traditional methods of naming inefficient. For instance, the Amphion class
is also known as the A
class. Most destroyer classes were known by the initial letter used in naming the vessels, e.g., V and W class destroyers
. Classification by letter also helped to conflate similar smaller classes of ships as in the case of the C-class destroyers of 1913
whose names spread across the alphabet. Since the end of the Second World War
, Royal Navy ship classes have also been known by their type number (e.g. Type 42 destroyer
Russian (and Soviet) ship classes are formally named by the numbered project that designed them. That project sometimes, but not always, had a metaphorical name, and almost always had a NATO reporting name
. In addition, the ships of the class would be numbered, and that number prefixed by a letter indicating the role of that type of vessel. For example, Project 641 had no other name, though NATO referred to its members as Foxtrot class submarines
. In contrast, Project 667AM was known in Russia as Navaga
, a type of cod
, and was given the NATO reporting name Yankee-II
. One boat of that class had no other name than K-219
, where the “K” stood for kreyserskaya
The West German
) used a three-digit type number for every class in service or in advanced project state. Modified versions were identified by a single letter suffix. After the reunification of Germany
the German Navy
) kept the system. Informally, classes are also traditionally named after their lead ships.
Merchant Vessel Class
Merchant ships are almost always classed by a classification society
. These vessels are said to be in class
when their hull, structures, machinery, and equipment conform to International Maritime Organization
standards. Vessels out of class
may be uninsurable and/or not permitted to sail by other agencies.
A vessel's class may include endorsements for the type of cargo such as "oil carrier", "bulk carrier", "mixed carrier" etc. It may also include class notations denoting special abilities of the vessel. Examples of this include an ice class, fire fighting capability, oil recovery capability, automated machinery space capability, or other special ability.