Fleet submarine

In the United States Navy, the term came to be used primarily for the long-range submarines that served in World War II.

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.

[2] 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.

[3] Although the Gato-class was considered the fully developed archetype,[4] the earlier Porpoise, Salmon, Sargo and Tambor-classes were incrementally improved prototypes distinctly different from the two contemporary experimental Mackerel-class coastal submarines.

[7] In order to get the speeds – over 20 knots while surfaced – required to match their capital ships and to be able to screen ahead of the fleet or flank the enemy, the British initially used steam propulsion.