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The ''Forrestal''-class aircraft carriers were a four-ship class designed and built for the United States Navy in the 1950s. It was the first class of so-called supercarriers, combining high tonnage, deck-edge elevators and an angled deck. The first ship was commissioned in 1955, the last decommissioned in 1998. == Design == The ''Forrestal'' class was the first completed class of "supercarriers" of the Navy, so called because of their then-extraordinarily high tonnage (75,000 tons, 25% larger than the post-World War II-era ''Midway'' class), full integration of the angled deck ( and were laid down as axial deck carriers and converted to angled deck ships while under construction; and were laid down as angled deck ships and had various minor improvements compared to the first two), a very large island and most importantly their extremely strong air wing (80–100 jet aircraft, compared to 65–75 for the ''Midway'' class and fewer than 50 for the ''Essex'' class). Compared to the ''Midway'' class, the ''Forrestal''s were longer and nearly wider abeam, resulting in a far more stable and comfortable aircraft platform even in very rough weather. When commissioned, the ''Forrestal''-class ships had the roomiest hangar decks and largest flight decks of any carrier ever built. Because of their immense size they were built to a new, deep-hulled design that incorporated the armored flight deck〔(USS FORRESTAL (CVA-59) ):"Over a dozen 1,000 and 500 pound bombs detonated within the first few minutes of the fire, punching holes through the 3" armor plating of the flight deck."〕〔Cracknell, W.H, Cmdr USN, ''Warship Profile 15, USS Enterprise (CVAN 65) Nuclear Attack Carrier'', p.56: "''The main armor carried on Enterprise is the heavy armored flight deck. This was to prove a significant factor in the catastrophic fire and explosions that occurred on Enterprise's flight deck in 1969. The US Navy learned its lesson the hard way during World War II when all its carriers had only armored hangar decks. All attack carriers built since the Midway class have had armored flight decks.''"〕 into the hull (previous American design practice was to design the flight deck as superstructure). This was a very similar structural design as used on British "armored" carriers, and grew out of the requirement for such a very large carrier, because carrying the strength deck at the flight deck level produced a stronger and lighter hull.〔Friedman, Norman, ''U.S. aircraft carriers: an illustrated design history'', Naval Institute Press, ISBN 0-87021-739-9, P.250〕 The ''Midway''-class ships sat very low in the water and were poor sea boats through their long careers; they were very wet forward and their aviation characteristics were poor. The deeper ''Forrestal'' hull allowed the ships more freeboard and better seakeeping. The ''Forrestal''-class carriers, like the ''Midway'' class that preceded it, were designed with armored flight decks.〔(CV-59 FORRESTAL class ):"As the first aircraft carrier designed specifically for jet aircraft, she featured an armored flight deck."〕〔(''Forrestal class attack aircraft carriers'' ):"Armor: hangar, flight deck and magazines protected"〕〔(Forrestal Class )〕〔(USS Forrestal Memorial (CVA/CV/AVT-59) July 29, 1967 ): "The explosions tore large holes in the armored flight deck..."〕 ''Forrestal''-class ships were the first examples of supercarriers and thus not quite a perfected design; their elevators in particular were badly arranged for aircraft handling. The portside elevator, a relic of the original axial-deck design, was especially poorly suited, as it was located at the fore end of the angled deck, in the landing path as well as the launch path of aircraft from the #3 and #4 catapults. The subsequent ''Kitty Hawk'' class moved the portside elevator to the aft end of the angle and reversed the position of the island and the second starboard elevator, vastly improving aircraft handling. The sponson-mounted guns suffered from poor range and complicated firing arcs, and were located in very wet and thus nearly useless positions in the bow and stern. They were removed after only a few years and were later replaced by missiles and much later by close-in weapon systems (CIWS). The aft guns in ''Forrestal'' lasted until the fire in 1967, then were removed and eventually replaced by missiles in the mid-70s. The original design of the ''Forrestal''-class ships would have had a very small, retractable island; this design had numerous problems (the mechanism to raise and lower the island was never perfected before the angled deck was added to the design) and smoke fouling of the deck was expected to be a severe problem due to lack of adequate venting. The redesign to an angled deck allowed a very large island, much larger than on previous carriers, giving unprecedented flexibility and control in air operations. In the late 1990s, the US offered Brazil a ''Forrestal''-class carrier, but the offer was declined on the grounds of significant operating costs; Brazil instead received from France the ''Foch'', which was renamed ''São Paulo''. All four ships have been struck from the Naval Vessel Register. One, ex-''Ranger'', was on donation hold as a potential museum ship, but as of September 2012, all four have been designated for dismantling.〔http://www.navsea.navy.mil/teamships/Inactiveships/pdf/Inactive_Fleet_Inventory10Dec2012.pdf〕 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「Forrestal-class aircraft carrier」の詳細全文を読む スポンサード リンク
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