Fleet submarine

A fleet submarine is a submarine with the speed, range, and endurance to operate as part of a navy's Battle Fleet. Examples of fleet submarines are the British K class and the American Gato class. Within the modern Royal Navy, the term is used for the British nuclear powered attack submarines.

The term was used by the United States Navy to distinguish submarines suitable for long range patrols in the Pacific Ocean from earlier classes such as the United States S-class submarines. The initial goal, pursued with frequent interruptions since the AA-1-class (aka T-class) launched 1918-19, was to produce a submarine with a surfaced speed of 21 knots to operate with the Standard-type battleships of the surface fleet. Most of the nine "V-boats" launched 1924-33 (V-1 through V-6) were either attempts to produce a fleet submarine or were long-range submarine cruisers. Eventually, a long range of 11,000 nautical miles (20,000 km) was combined with high speed, beginning with the Salmon-class launched in 1938, to allow sustained operations in Japanese home waters while based at Pearl Harbor. These qualities also proved important in the Pacific commerce raiding of World War II, but the 1922 Washington Naval Treaty's prohibition on unrestricted submarine warfare precluded inter-war planning in this area. Although the Gato-class was considered the fully developed archetype, the earlier Porpoise, Salmon, Sargo and Tambor-classes were incrementally improved prototypes distinctly different from the two contemporary experimental Mackerel-class coastal submarines. The Tambors were fully developed and similar to the Gatos except for diving depth and separation of the engines into two compartments.

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