STATUS: Commissioned, in Active Service
SHIPS-IN-CLASS (2): JDS Hyuga (DDH-181); JDS Ise (DDH-182)
PROPULSION: 2 x COGAG Gas turbines connected by gears to 1 x shaft delivering 100,000 shaft horsepower combined.
Detailing the development and operational history of the JS Hyuga (DDH-181) Helicopter Carrier / Destroyer Warship.
Entry last updated on 12/18/2018.
Authored by JR Potts, AUS 173d AB. Content ©www.MilitaryFactory.com.
Japan is a nation of 6,852 islands located in the Pacific Ocean, east of the Sea of Japan with the Sea of Okhotsk to the north and the East China Sea to the south. Her suspect neighbors are China and North Korea, both having large submarine fleets that could be a threat to her lifeline import shipping lanes that support the Japanese economy. Tensions with Russia concerning several island collections to the north are also noted. Unlike the United States, the Japan Maritime Self Defense Force (JMSDF) does not see the need to project its power on the seas around the world using the CV-class of aircraft carriers. Instead, the Japanese navy requires ASW (Anti-Submarine Warfare) defense and rescue support around her local waters. As such, she has gone on to build a comparably large escort destroyer-type vessel with a flat-top deck with the appearance akin to an aircraft carrier. The vessel is known under the name of "Hyuga" and is the lead ship of her Hyuga-class. Her construction was begun at the IHI Marine United Shipyard in Yokohama in 2002 and she was officially commissioned on March 18th, 2009.
Known formerly as the CVH Hyuga DDH-181, the vessel can support up to 11 navalized helicopters and (some sources state) as many as 22 "jump jet" type aircraft, presumably the up-and-coming Lockheed F-35 Lightning II Joint Strike Fighter (JSF). She maintains a flush landing deck and starboard side island superstructure which makes her appear as a conventional aircraft carrier - or helicopter carrier in the least. Her standard air wing consists of three Mitsubishi SH-60K helicopters (based on the American Sikorsky S-70) and produced locally by Mitsubishi though with Japanese avionics and equipment for specialized search and rescue functions. Additionally, she carries one AgustaWestland MCH-101 Anti-Submarine Warfare (ASW) utility helicopter. When fully loaded, the Hyuga displaces at 18,000 tons or more and can make 30 plus knots. The speed maximum was accomplished by using a COmbined Gas turbine And Gas turbine propulsion system (COGAG) for ships using two gas turbines connected to a single propeller shaft. A gearbox and clutches allow either of the turbines to drive the shaft or both of them combined. Fuel efficiency is obtained when the smaller turbine system is near the its maximum setting.
JS Hyuga (DDH-181) (Cont'd)
Helicopter Carrier / Destroyer Warship
Despite her carrier-like qualities, the armament suite of the Hyuga leans towards the destroyer escort role for she fields 16 x RIM-162 "Evolved Sea Sparrow Missiles" (ESSM) used to protect the ship against inbound missile threats or airborne enemy aircraft. ESSM engine is more powerful than the original Sea Sparrow missile and can be loaded into the Mk 41 VLS (Vertical Launch System) onboard missile storage and firing system. 4 x ESSMs are carried in four of the 16 x Mk 41 VLS cells. The ship also carries 12 x RUM-139 VL-ASROC anti-submarine missiles produced Lockheed Martin and can be fired from the remaining cells of the Mk 41 VLS. Additional ASW threats are countered by 2 x triple 324mm torpedo tubes firing "Hunter-Killer" torpedoes against submerged enemy submarines. For last ditch, close-in protection from inbound missile and aircraft, these resides the computer-guided 20mm Phalanx CIWS (Close-In Weapon System). The rate-of-fire for the Gatling type cannon is 3,000 to 4,500 rounds per minute. However, destruction of inbound threats as close as 500 meters is expected to damage the ships sensors and processing systems and even exposed crew members. Anti-personnel and extremely close-in anti-aircraft defense weapons include 4 x 12.7mm heavy machine guns.
On board sensor systems are controlled and processed by the Advanced Technology Command System (ATECS). Directing the combat systems is an advanced OYQ-10 unit. For inbound missiles or aircraft there is the FCS-3 AAW system, a small version of the American "Aegis" phased array radar suite. Submarine threats are covered by the OQQ-21 ASW sensor and electronic warfare blocking is handled by the NOLQ-3C EW. For scanning for low flying missile threats there is the OPS-20C radar.
The Hyuga and her sister ship were built to be the flagship of any JMSDF flotilla rescue or combat operations such as the relatively recent Fukushima nuclear power disaster following the March 2011 Tsunami. The nuclear disaster left nearly 26,000 people dead or unaccounted for and triggered the world's biggest nuclear crisis since Chernobyl in 1986. Both the Hyuga and the Ise (commissioned on March 16th, 2011) were sent to the disaster site for rescue operations.