Afleet submarine is asubmarine with the speed, range, and endurance to operate as part of a navy's battlefleet. Examples of fleet submarines are the British First World War eraK class and the American World War II eraGato class.^{[citation needed]}

The term has survived in Britain to refer to modern nuclear-poweredattack submarines. In the United States Navy, the term came to be used primarily for the long-range submarines that served in World War II.^{[citation needed]}

The term was used by theUnited States Navy to distinguish submarines suitable for long range patrols in thePacific Ocean from earlier classes such as theUnited States S-class submarines. The initial goal, pursued with frequent interruptions since theAA-1-class (akaT-class) launched 1918–19, was to produce a submarine with a surfaced speed of 21 knots to operate with theStandard-type battleships of the surface fleet.^[1] Most of the nine "V-boats" launched 1924–33 (V-1 throughV-6) were either attempts to produce a fleet submarine or were long-rangesubmarine cruisers. Eventually, a long range of 11,000 nautical miles (20,000 km) was combined with high speed, beginning with theSalmon-class launched in 1938, to allow sustained operations inJapanese home waters while based atPearl Harbor.^[2] These qualities also proved important in the Pacific commerce raiding ofWorld War II, but the 1922Washington Naval Treaty's prohibition onunrestricted submarine warfare precluded inter-war planning in this area.^[3] Although theGato-class was considered the fully developed archetype,^[4] the earlierPorpoise,Salmon,Sargo andTambor-classes were incrementally improvedprototypes distinctly different from the two contemporary experimentalMackerel-class coastal submarines. TheTambors were fully developed and similar to theGatos except for diving depth and separation of the engines into two compartments.^[5][6]

JapaneseI-boats were a conceptually similar long-range differentiation from smaller "medium" or "sea-going"Ro-boats, although some I-boats had features like aircraft hangars and large-caliberdeck guns more often associated withsubmarine cruisers.^[7]

In order to reach the speeds – over 20 knots while surfaced – required to match theircapital ships and to be able to screen ahead of the fleet or flank the enemy, the British initially used steam propulsion. TheK-class entering service in 1916 were large for their time. Although able to achieve 24 knots, the complexity of shutting down boilers and stowing funnels made them slow to dive.^[8]

As the speed of capital ships increased, the United Kingdom abandoned the fleet submarine concept following completion of three 21-knotRiver-class submarine submarines of the early 1930s using supercharged diesels, because the size required for range and surface speed decreased maneuverability.^[9]

Continental European nations sometimes used the terms "ocean-going", "long-patrol", "type 1" or "1st class" submarines, generally referring toAtlantic orIndian Ocean operations in the absence of anticipated need for Pacific patrols, and often without the speed for fleet operations.^[10]

Since the mid-1960s, theRoyal Navy has used the term Fleet Submarine for itsnuclear-powered attack submarines, distinguishing them from theballistic missile submarines (and, in the 20th century, from thediesel-electric submarines, which it termed 'Patrol Submarines').^[28]

• Alden, John D., Commander (USN Ret) (1979).The Fleet Submarine in the U.S. Navy: A Design and Construction History. London: Arms and Armour Press.ISBN 0-85368-203-8.{{cite book}}: CS1 maint: multiple names: authors list (link)
• Friedman, Norman (1995).U.S. Submarines Through 1945: An Illustrated Design History.Annapolis, Maryland:United States Naval Institute.ISBN 1-55750-263-3.
• Kafka, Roger; Pepperburg, Roy L. (1946).Warships of the World. New York: Cornell Maritime Press.
• le Masson, Henri (1969).Navies of the Second World War. Vol. The French Navy 1. Garden City, New York: Doubleday & Company.
• Lenton, H.T. (1968).Navies of the Second World War. Vol. Royal Netherlands Navy. Garden City, New York: Doubleday & Company.
• Lenton, H.T.; Colledge, J.J. (1964).British and Dominion Warships of World War II. Garden City, New York: Doubleday & Company.
• Potter, E.B.;Nimitz, Chester W. (1960).Sea Power. Englewood Cliffs, New Jersey: Prentice-Hall.
• Silverstone, Paul H. (1968).U.S. Warships of World War II. Garden City, New York: Doubleday & Company.
• Taylor, J.C. (1966).German Warships of World War II. Garden City, New York: Doubleday & Company.
• Watts, Anthony J. (1966).Japanese Warships of World War II. Garden City, New York: Doubleday & Company.

• Submarines by type

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