Editing Tacoma-class frigate (section)

==Design==
In 1942, the success of [[Nazi Germany|German]] [[submarine]]s against [[Allies of World War II|Allied]] shipping and the shortage of escorts with which to protect Allied [[sea lines of communication]] convinced US President [[Franklin D. Roosevelt]] of a need to engage mercantile shipbuilders in the construction of warships for escort duty. The [[United States Maritime Commission]] (MARCOM), which oversaw the wartime merchant shipbuilding program, proposed to meet this requirement by building a version of the British [[River-class frigate|''River''-class frigate]], a [[Royal Navy]] ship type based on a [[merchant ship|mercantile]] design in British shipyards experienced in building commercial ships.<ref name="Russell p. 22">Russell, Richard A., ''Project Hula: Secret Soviet-American Cooperation in the War Against Japan'', Washington, D.C.: [[Naval Historical Center]], 1997, {{ISBN|0-945274-35-1}}, p. 22.</ref><ref name="Conway's 1922-1946">Gardiner, Robert, ed., ''Conway's All the World's Fighting Ships 1922–1946'', New York: Mayflower Books, 1980, {{ISBN|0-8317-0303-2}}, pp. 148–149.</ref> Two ''River''-class ships under construction in [[Montreal, Quebec]], Canada, as {{HMS|Adur|K296|6}} (for the Royal Navy) and {{HMCS|Annan|K297|6}} (for the [[Royal Canadian Navy]]), were transferred to the US Navy in 1942, prior to completion, as prototypes for the ''Tacoma'' class and became the {{sclass|Asheville|frigate|0}} {{USS|Asheville|PF-1|3}} and {{USS|Natchez|PF-2|3}}, respectively.

The [[naval architecture]] firm of [[Gibbs & Cox]], designed the ''Tacoma'' class by modifying the River class to American requirements. The ''Tacoma''-class units were designed and armed to serve mostly as [[anti-submarine warfare]] (ASW) ships. They were distinguished from the River class primarily by their pole (instead of the British tripod) [[foremast]] and lighter main guns, [[3"/50 caliber gun|{{convert|3|in|sigfig=3|adj=on|abbr=off}}/50 caliber gun]] instead of the British [[QF 4 inch Mk XIX naval gun|{{convert|4|in|sigfig=3|adj=on|abbr=off}}/40 caliber gun]], and they had an American rather than British powerplant.

The ''Tacoma''-class was designed to take advantage of American construction techniques employing [[prefabrication]]. Unlike most other types of warship, the ''Tacoma''s, like the ''Rivers'', were built to mercantile standards. With the proven effectiveness of the ''River'' class on escort duty, MARCOM's goal was to allow commercial shipyards without prior experience of naval construction standards to build effective warships more cheaply and efficiently. MARCOM had hoped that the US Navy, some members of which doubted that the commercial shipyards could build a sturdy enough warship, would accept them because of the proven service record of the ''River''-class ships which inspired their design.<ref name="Russell p. 22"/><ref name="Conway's 1922-1946"/>

The resulting ships had a greater range than the superficially similar [[destroyer escort]]s, but the US Navy viewed them as decidedly inferior in all other respects. The ''Tacoma'' class had a much larger turning circle than a destroyer escort, lacked sufficient ventilation for warm-weather operations – a reflection of their original British design and its emphasis on operations in the North Atlantic Ocean – and were criticized as far too hot below decks, and, because of the mercantile style of their hulls, had far less resistance to underwater explosions than ships built to naval standards like the destroyer escorts.<ref name="Conway's 1922-1946"/>

Like their predecessors ''Asheville'' and ''Natchez'', the ''Tacoma''-class ships built for the US Navy all were named after small cities in the United States.<ref name="Russell p. 22"/>