March 28, 2015 By Franz-Stefan Gady – The Diplomat

Japan now has all the building blocks to field a powerful carrier strike group.

This week, Japan’s Maritime Self-Defense Force commissioned the JDS Izumo (DDH-183), a helicopter destroyer, in a ceremony at the JMSDF Yokosuka naval base in Yokohama.

The new carrier’s principal task, although touted as a multi-purpose vessel, will be anti-submarine warfare and command-and-control operations to protect Japanese territories in the East China Sea.

“This heightens our ability to deal with Chinese submarines that have become more difficult to detect,” one Japanese official noted. According to other  JMSDF officials, the ship will also be used for humanitarian aid and disaster relief (HADR) operations.

With a 27,000 tons displacement when fully loaded (some sources state 24,000 tons), the 248 m-long  Izumo-class helicopter carrier is the largest surface combatant in the Japanese fleet to date, and substantially bigger than its predecessor, the Hyūga-class, which yielded 19,000 tons.

The ship will have a crew of around 470 and also can carry up to 400 JSDF troops.  IHS Jane’s Defence Weekly notes about the vessels’s specifications:

Izumo is equipped with an OQQ-22 bow-mounted sonar for submarine prosecution while air defence is provided by two Raytheon RIM-116 Rolling Airframe Missile SeaRAM launchers and two Phalanx close-in weapon systems. (…)

[I]t can embark Sikorsky/Mitsubishi SH-60K Seahawk anti-submarine warfare helicopters and the Izumo class’s air wing will also include two airborne mine countermeasures versions of the Kawasaki Heavy Industries/AgustaWestland MCH-101 helicopter – JMSDF officials claim that the ship will be deployed mainly for border surveillance and humanitarian assistance and disaster relief missions. (..) Officials in Tokyo have also suggested it will embark Bell-Boeing V-22 Osprey tilt-rotor aircraft.

The ship is designed to accommodate up to 14 helicopters (seven Mitsubishi-built SH-60k ASW helicopters and seven Agusta Westland MCM-101 mine countermeasure helicopters), five of which can simultaneously take off and land, given the Izumo’s large flight deck and five landing spots.

USNI News notes that the Izumo could also accommodate fixed wing aircraft – perhaps up to 27 total:

The ship would also be able to field American MV-22s and potentially the short takeoff and vertical landing variant of the Lockheed Martin F-35 Lighting II Joint Strike Fighter (JSF), however Japanese defense officials have repeatedly said they have no plans to use the JSF on the Izumo.

The new carrier is slightly larger than other light carriers, such as the Italian Cavour and the Spanish Principe de Asturias – both of which carry fixed wing aircraft. Total costs of the ship are billed at about 120 billion yen ($1 billion), although they may be as high as $ 1.5 billion.

The naming of the vessel caused some controversy. “[T]he name Izumo itself has historical baggage: the original Izumo, an armored cruiser that participated in the Battle of Tsushima, was purchased with reparations from the first Sino-Japanese War. There is little doubt all parties, particularly the Chinese, are aware of the lineage,” one analyst noted.

The new carrier joined the MSDF’s Escort Flotilla 1 based in Yokosuka, Kanagawa Prefecture. The JS Izumo’s sister ship, also constructed by the IHI Marine United Yokohama Shipyard (which already built the Hyūga-class helicopter destroyers), will be launched this August and is scheduled to be commissioned in March 2017.