Haruna-class destroyer

{{Short description|Class of Japanese warships}}

{{Infobox ship begin}} {{Infobox ship image |Ship image=File:JDS Hiei.jpg |Ship caption=Hiei (DDH-142) at Pearl Harbor in 2006 }} {{Infobox ship class overview |Name=Haruna class |Builders= Ishikawajima-Harima HI (1) Mitsubishi Heavy Industries Nagasaki Shipyard (1) |Operators={{navy|Japan}} |Class before= |Class after={{sclass|Shirane|destroyer|4}} |Subclasses= |Cost= |Built range=1970–1973 |In service range= |In commission range= 1973–2011 |Total ships building= |Total ships planned= |Total ships completed=2 |Total ships cancelled= |Total ships active= |Total ships laid up= |Total ships lost= |Total ships retired=2 |Total ships preserved= }} {{Infobox ship characteristics |Hide header= |Header caption= |Ship class= |Ship type=Destroyer |Ship displacement=*{{convert|4950|LT|t|0}} standard {{convert|6900|LT|t|0}} full load |Ship length= {{convert|153.1|m|ft|abbr=on}} |Ship beam= {{convert|17.5|m|ftin|abbr=on}} |Ship draft={{convert|5.2|m|ftin|abbr=on}} |Ship propulsion=*2 boilers 850 psi (60 kg/cm², 5.9 MPa), 430 °C 2 turbines 2 shafts {{convert|60000|hp|kW|lk=in|abbr=on}} |Ship speed= {{convert|31|kn|mph km/h|lk=in}} |Ship range= |Ship endurance= |Ship complement=*370 360 (DDH-141) 36 officers |Ship sensors= |Ship EW= |Ship armament=*Sea Sparrow Mk.29 SAM octuple launcher ASROC octuple launcher 2 × 5"/54 caliber Mk.42 guns (Type 73) 2 × 20 mm Phalanx CIWS 2 × Mark 32 triple torpedo tubes (Mk-46 torpedoes) |Ship armor= |Ship aircraft= 3 × SH-60J(K) anti-submarine helicopters |Ship aircraft facilities= |Ship notes= }}

The Haruna-class destroyer was a destroyer class built for the Japan Maritime Self-Defense Force (JMSDF) in the early 1970s. These helicopter-carrying destroyers (DDH) were built around a large central hangar which housed up to three helicopters.

Originally, the Coastal Safety Force and its successor, the JMSDF, had intended to enable its fleet aviation operating capability. In 1960, the Defense Agency planned to construct one helicopter carrier (CVH) with the Second Defense Build-up Plan, but this project was shelved and finally cancelled because the JMSDF changed their plan to dispersing its fleet aviation assets among destroyers, not concentrating in a few helicopter carriers.{{Cite web|author=National Diet Library|date=1987-05-19|url=http://kokkai.ndl.go.jp/cgi-bin/KENSAKU/swk_dispdoc.cgi?SESSION=20792&SAVED_RID=3&PAGE=0&POS=0&TOTAL=0&SRV_ID=6&DOC_ID=9004&DPAGE=1&DTOTAL=1&DPOS=1&SORT_DIR=1&SORT_TYPE=0&MODE=1&DMY=16329|title=the record of the proceedings of the budget committee (vol.15)|access-date=2012-10-08}} The Japanese DDH was planned to be a hub with this dispersing fleet aviation concept with their logistics service capability for aircraft.{{Cite journal|date=June 2011|title=History of Japanese destroyers since 1952|journal=Ships of the World|issue=742|pages=91–97|publisher=Kaijin-sha|language=ja}}

At the beginning, equipment of this class were similar to those of the {{sclass|Takatsuki|destroyer|0}} DDA. All weapons, two 5-inch/54 caliber Mark 42 (Type 73) guns and one Type 74 octuple missile launcher (Japanese version of the American Mark 16 GMLS), were settled on the forecastle deck. But with the Fleet Rehabilitation and Modernization (FRAM) program in 1983 and 1984, Sea Sparrow launchers, Phalanx CIWS systems and chaff launchers were added on the superstructure.{{Cite journal|date=March 2010|title=2. Guns (Shipboard weapons of JMSDF 1952-2010)|journal=Ships of the World|issue=721|pages=88–93|publisher=Kaijin-sha|language=ja}}{{Cite journal|date=March 2010|author=Keiichi Nogi|author-link=:ja:江藤巌|title=1. Missiles (Shipboard weapons of JMSDF 1952-2010)|journal=Ships of the World|issue=721|pages=82–87|publisher=Kaijin-sha|language=ja}} The upgrade program also added the Naval Tactical Data System (NTDS) with the OYQ-6/7 combat direction system.{{Cite journal|author=Makoto Yamazaki|date=October 2011|title=Combat systems of modern Japanese destroyers|journal=Ships of the World|issue=748|pages=98–107|publisher=Kaijin-sha|language=ja}}

The rear half of the superstructure was helicopter hangar, and the afterdeck was the helicopter deck with a beartrap system. To operate large HSS-2 ASW helicopters safely, the full length of the helicopter deck reached 50 meters.{{Cite journal|date=October 2008|title=Aviation equipment of JMSDF ships|journal=Ships of the World|issue=696|pages=100–103|publisher=Kaijin-sha|language=ja}}