CL/CA - Light and Heavy Cruisers
When the Navy formally implemented its hull number system in July 1920, it redesignated thirteen scout cruisers (three completed in 1908, plus ten new ships which were still under construction) as "Light Cruisers" (CL), numbered in accordance with the previous scout cruiser number series. About a year later, nine older protected cruisers (eight of which had been briefly classified as "Gunboats" during 1920-21) were added to the CL number series. An additional CL series number (CL-14) was intended for a tenth such ship, but it was not formally assigned.
In 1926, construction began on a new group of light cruisers, armed with eight-inch guns instead of the six-inch or smaller weapons carried by the existing CLs. Eight of these were completed between late 1929 and early 1931 as CL-24 through CL-31. At the beginning of July 1931, these eight ships were redesignated as "heavy cruisers" (CA), based on warship classifications established by the previous year's London Naval Treaty, but their hull numbers were not changed.
All subsequent U.S. Navy light and heavy cruisers were numbered in the same series, which ultimately encompassed 160 ships, all but one resulting from building programs of 1945 or earlier. Ten of these were completed for other purposes and construction of another thirty-seven was cancelled. The final number in the series (CLGN-160) was briefly assigned to the new nuclear-powered guided missile cruiser Long Beach during 1956-57, before she was laid down. No further ships have been built in the CL/CA series, and its few surviving members are now in museum status, so the designation can be safely considered extinct.
In addition to the lengthy CL/CA hull number series, the U.S. Navy has maintained several other number series for cruisers. Among these are the twenty-two ship "Cruiser" (frequently shortened to "C-#") series applied to protected cruisers of the late 19th Century era; the first CA series (sometimes rendered as "ACR") for contemporary armored cruisers, which was extended in 1920 to include some of the larger surviving protected cruisers; the six-ship large cruiser (CB) series of 1940; the six-ship battle cruiser (CC) series of 1916-1922; the three command ships (CLC & CC) of the 1950s and 1960s; and the extensive guided-missile cruiser (CAG, CLG & CG) series that began in the 1950s and continues in use to the present day. Links to pages covering these series are provided below.