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Destroyer escort (DE) was the United States Navy mid-20th century classification for a warship designed with endurance to escort mid-ocean convoys of merchant marine ships.〔Blackman, pp.393&394〕 ''Kaibōkan'' were designed for a similar role in the Imperial Japanese Navy.〔 The Royal Navy and Commonwealth forces identified such warships as frigates, and that classification was widely accepted when the United States redesignated destroyer escorts as frigates (FF) in 1975. Destroyer escorts, frigates and ''kaibōkan'' were mass-produced for World War II as a less expensive anti-submarine warfare alternative to fleet destroyers.〔Potter & Nimitz, p.550〕 Post-war destroyer escorts and frigates were larger than those produced during wartime, with increased anti-aircraft capability, but remained smaller and slower than post-war destroyers.〔Cooney, pp.6&7〕 As Cold War destroyer escorts became as large as wartime destroyers, the United States Navy converted some of their World War II destroyers to escort destroyers (DDE).〔NAVPERS, pp.32&35〕 ==General description== Full-size destroyers must be able to steam as fast or faster than, the fast capital ships such as fleet carriers and cruisers. This typically requires a speed of 25-35 knots (dependent upon the era and navy). They must carry torpedoes and a smaller caliber of cannon to use against enemy ships, as well as anti-submarine detection equipment and weapons. A destroyer escort needed only to be able to maneuver relative to a slow convoy (which in World War II would travel at 10 to 12 knots), and be able to defend against aircraft and detect, pursue and attack submarines. These lower requirements greatly reduce the size, cost, and crew required for the destroyer escort. Destroyer escorts were optimized for anti-submarine warfare, having a tighter turning radius and more specialized armament (such as the forward-firing "Hedgehog" weapon) than fleet destroyers. Their much slower speed was not a liability in this context, since sonar was useless at speeds over 20 knots. Destroyer escorts were also considerably more sea-kindly than corvettes. As an alternative to steam turbine propulsion found in full size destroyers and larger warships, many US destroyer escorts of the World War II period had diesel-electric or turbo-electric drive, in which the engine rooms functioned as power stations supplying current to electric motors sited close to the propellers. Electric drive was selected because it does not need gearboxes (which were heavily in demand for the fast fleet destroyers) to adjust engine speed to the much lower optimum speed for the propellers. The current from the engine room can be used equally well for other purposes, and post-WWII many destroyer escorts were recycled as floating power stations for coastal cities in Latin America under programs funded by the World Bank. Destroyer escorts were also useful for coastal anti-submarine and radar picket ship duty. During World War II, seven DEs were converted to radar picket destroyer escorts (DERs), supplementing radar picket destroyers. Although these were relegated to secondary roles after the war, in the mid-1950s twelve more DEs were converted to DERs, serving as such until 1960-1965. Their mission was to extend the Distant Early Warning line on both coasts, in conjunction with sixteen Guardian-class radar picket ships, which were converted Liberty ships. In World War II, some 95 destroyer escorts were converted by the US to High-speed transports (APDs). This involved adding an extra deck which allowed space for about 10 officers and 150 men. Two large davits were also installed, one on either side of the ship from which landing craft (LCVP) could be launched. The modern Littoral Combat Ship also adds transport and boat launching capabilities to a ship smaller than a destroyer. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Destroyer escort」の詳細全文を読む スポンサード リンク
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