Hatsuyuki-class destroyer

The Hatsuyuki class destroyer is a class of Japanese destroyer, serving with the Japan Maritime Self-Defense Force (JMSDF). It was the third generation of general purpose destroyers, though like its predecessor, the Yamagumo-class destroyer, the main task is anti-submarine warfare. The class was completed between 1982 and 1987. Due to its size it would be more appropriately classed as a frigate.

Design and development
This class is made a number of firsts among general purpose destroyers of the JMSDF.

It was the first class to use Combined gas or gas (COGOG) propulsion system. The all-gas-turbine propulsion system is composed of two Kawasaki-Rolls-Royce Tyne RM1C gas turbines for cruising and two Kawasaki-Rolls-Royce Olympus TM3B gas turbines for high speed operation. It introduced the concept of total ship systems engineering with an integrated combat system. The core of the combat system is the OYQ-5 Tactical Data Processing System (TDPS). The OYQ-5 TDPS is composed of one AN/UYK-20 computer and five OJ-194B workstations, and capable of receiving data automatically from other ships via Link-14 (STANAG 5514).

This is the first destroyer class in the JMSDF equipped with the Sea Sparrow Improved basic point defense missile system and Boeing Harpoon surface-to-surface missile system for AAW and ASuW respectively. The IBPDMS of this class uses FCS-2 fire-control systems of Japanese make and one Mk.29 octuple launcher at the afterdeck.

The class introduced the capability to operate an ASW Helicopter. While the JMSDF already had the Haruna class of "helicopter destroyer", the Hatsuyuki class were the first air-capable general purpose destroyer class. Although it has a small aviation deck, through a beartrap system, the class can operate the Sikorsky HSS-2B Sea King anti-submarine helicopter safely in a wider range of weather conditions.

The Shirayuki (DD-123) was retrofitted with the Phalanx CIWS system in early 1982, the modification was then applied to the rest of the class gradually - being completed by 1996. The Matsuyuki (DD-130) was fitted with a towed sonar array in 1990, followed by the Hatsuyuki (DD-122) in 1994, work ongoing to apply the fit to the rest of the class. From DD-129 onwards, steel replaced aluminium for key elements of the superstructure, including the bridge, this increased the overall displacement.

Hatsuyuki and Shirayuki are named after World War II destroyers.

Shimayuki (DD-133) was re-classed as a training vessel on 18 March 1999.

As of March 5th 2013, it was being reported that the Japanese government were considering the transfer of four small destroyers [frigates] (later confirmed to be of the Hatsuyuki class) from the MSDF to the Japan Coast Guard, in light of the extreme strains on the latter's resources due to current events. Of the four, one has already been decommissioned (in March 2013), with the other three to decommission over the course of FY2013. If the transfer goes ahead, the four vessels will likely be modified to JCG requirements (e.g. removal of the Harpoon launchers) and redesignated as PLHs.