Japanese Aircraft Carrier

Paragraph 2 of Article 9 of the Constitution provides that "the right of belligerency of the state will not be recognized." The self-defense capability that Japan is permitted to possess is limited to the minimum necessary by the constitutional limitations. However, whether or not the said armed strength corresponds to "war potential" stipulated in paragraph 2 of Article 9 of the Constitution is an issue regarding the total strength that Japan possesses. Accordingly, whether the SDF are allowed to possess some specific armaments depends on the judgment whether its total strength will or will not exceed constitutional limitations by possessing such armaments. But in any case in Japan, it is unconstitutional to possess what is referred to as offensive weapons that, from their performance, are to be used exclusively for total destruction of other countries, since it immediately exceeds the limit of the minimum necessary level of self-defense. Therefore, for instance, the SDF is not allowed to possess ICBMs, long-range strategic bombers or offensive aircraft carriers.

Japan has long wanted to develop an aircraft carrier. As early as 1983, Japan called for the building of a 20,000-ton aircraft carrier, which could carry 20 helicopters or 20 VTOL Sea Harriers. This was not realized owing to opposition from the United States. The US Navy strongly opposed to the plan, and urged Japan to build more destroyers instead. The US Navy had enough flattops to counter the Soviet Navy but lacked destroyers. The MSDF's plan to own a light flattop raised Washington's eyebrow, apparently taken as a subcontractor attempting to strike out on its own.

That did not daunt the Defense Agency or the MSDF. In a Diet budget session in April 1988, then Defense Agency chief Tsutomu Kawara replied, "The Self-Defense Forces are not allowed to possess ICBMs (intercontinental ballistic missile), strategic bombers, or attack aircraft carriers." Until the 1970s in the US Navy, large-scale flattops had been categorized as "attack aircraft carriers" and small flattops as "antisubmarine aircraft carriers." Prohibition of having attack aircraft carries can be taken to mean allowing possession of small aircraft carriers.

With the decline of Russian naval strength, the Self- Defense Forces' fighting vessels and aircraft rank second in the world, behind the United States. However, the Self-Defense Forces still maintain an ambition to develop an aircraft carrier and nuclear submarine. It is said that the plan to build DDH helicopter destroyer is actually another demonstration of such ambition.

Mention of a light aircraft carrier was first made in the 2001-2005 National Defense Buildup Program Outline (Mid-term Program) that was approved by the Cabinet in December 2000. According to a designer's concept shown by the agency in December 2000, the vessel's bridge was located amidships to bisect the flight deck-a ship design that was effectively identical to its predecessor. But when it became time for the fiscal 2004 budget request in August 2003, the agency came up with a completely new drawing, which showed the bridge on starboard to create a through deck-a design of none other than an aircraft carrier. The agency, however, insists that since this vessel is just an expanded model of any conventional flagship DDH, it ought to be categorized as such.

"The "16DDH"-class ship has attracted significant media and Diet attention, owing to its resemblance to an aircraft carrier. The first officially released design was a unique configuration that featured forward and aft helicopter pads with a hanger in the center. However, in the end, the design that most fit the JMSDF's need - aircraft carrying capability - was choosen, which strongly resembled a normal aircraft carrier.

The vessel's design features a starboard-side island superstructure and an uninterrupted flight deck, prompting observers to speculate that Japan may be eyeing a carrier capable of handling Harrier-like aircraft. Notes one analyst, "The configuration of the Osumi and the new DDH class indicates that Japan is rehearsing carrier-building technology to reserve for itself this potential military option; and thus, that it is considering discarding the constitutional prohibition on the acquisition of power-projection capabilities." In the meantime, the 16DDH would fulfill many of the peacetime and wartime missions elaborated in the NDPG. As a wartime flagship, the 16DDH would serve as a command-and-control platform, coordinating the activities of other units while its organic helicopters conducted ASW operations. During peacetime operations, or "military operations other than war" (MOOTW), the 16DDH would join the Osumi-class ships for peacekeeping and relief operations, as well as the "diverse situations" Japan foresees confronting on the high seas." [Yoshihara & Holmes, Summer 2006]

It is almost as large as the Imperial Japanese Navy's Tone class heavy cruisers. It matches in size modern small aircraft carriers as Italy's MM Giuseppe Garibaldi (10,100 tons) and Spain's Principe de Asturia (17,188 tons). In terms of displacement, the two destroyers -- not nuclear-powered -- will be in the class of Britain's Invincible, a 20,600-ton light flattop, when they are fully loaded with fuel.

The JMOD FY2010 budget request included 116.6 billion Yen for a new 22DDH "helicopter destroyer" built to a design signficiantly larger than the 16DDH Hyuuga Class. After Yukio Hatoyama became prime minister in September 2009, new budget requests were submitted in October 2009 -- including 118.1 billion yen for the construction of a helicopter destroyer. The ship would eventually replace the destroyer Shirane, which was scheduled to be decommissioned in fiscal 2014. A request for the helicopter destroyer was first made for the fiscal 2010 budget when the Liberal Democratic Party was in control of government.

It is designed to be a vessel which is conscious of the Chinese Navy, and to support civil disaster relief operation and the United Nations Peace Keeping Operations (PKO). The planned helicopter destroyer will have a length some 25% greater than the 197 meter 16DDH Hyuuga. At 248 meters [813 feet] the 22DDH is comparable to the Italian Cavour of 244 meters [some reports claim 284 meters or 925 feet for the 22DDHH, but this seems to be wrong]. The full-length aircraft carrier type deck extends from the bow to the stern. The light displacement was reported as 19,500 tons, a 44% increase over the 16DDH, while the full loaded displacement is probably comparable to the 27,000 ton displacement of the Italian Cavour.

The 22DDH Class helicopter destroyer is Japan's first aircraft carrier since the Great Pacific War. The designation 22DDH is short for helicopter destroyer project, Heisei Year 22. Heisei is the name of the reign of the current emperor. Each emperor's reign is named, i.e. Meiji, Showa, etc. Heisei 22 is the 22nd year of rule by Emperor Akihito. The 22 does not reference the displacement, and in any event Asian navies always disclose empty displacement instead of loaded or full displacement.

All six of Japan's first-line aircraft carriers, Akagi, Kaga, sister ships Soryu and Hiryu, and sister ships Shokaku and Zuikaku, were assigned to the mission. With over 420 embarked planes, these ships constituted by far the most powerful carrier task force ever assembled. The 22DDH Class helicopter destroyer is longer and has a larger flight deck than any of these carriers.

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