Kunigami-class patrol vessel

PL-01 Oki
Class overview
Name	Kunigami-class patrol vessel
Operators	Japan Coast Guard
Preceded by	Hateruma class
Succeeded by	Iwami class
Subclasses	Teresa Magbanua class
In commission	2012–present
Planned	21
Building	1
Completed	20
Active	20
General characteristics
Type	PL (Patrol vessel Large)
Tonnage	1,700 GT
Length	96.6 m (316 ft 11 in)
Beam	11.5 m (37 ft 9 in)
Draft	5.2 m (17 ft 1 in)
Propulsion	2 × shafts 2 × diesel engines
Speed	25 knots (46 km/h; 29 mph)
Armament	1 × JM61 20mm gun or Bushmaster II 30mm gun

The Kunigami-class patrol vessel (くにがみ型巡視船, Kunigami-gata-junnsi-senn) is a class of 1,000 ton-class PL type patrol vessels of the Japan Coast Guard (JCG).

Background

In the 2000s, the JCG was building 1,000-ton class PLs with a high speed planing hull, such as Aso and Hateruma classes. Although these ships were excellent in security missions, they were also unsuitable for rescue missions because of their poor low-speed stability and cruising capacity.^[1]

Since the mass retirement of the Shiretoko class was planned in the 2010s, general-purpose ships as replacements were needed. For this purpose, construction of this class was started under the FY2009 supplement budget.^[2]

As a result of emphasis on versatility, the price soared, only two ships were built, more reasonable Iwami class was built from the following fiscal year. However, after that, additional construction was done to deploy on the Senkaku Islands in the FY2012 budgets. And construction is continuing from FY 2013 onwards, as construction costs have been reduced due to the mass production effect of this large-scale construction.^[2]

Design

Due to the demand for multi-mission capabilities, displacement hull made of steel was adopted. Also, since low-speed stability was required, antiroll tanks was also installed in addition to fin stabilizers. The superstructure is made of aluminium alloy, but the bridge has bulletproofing structure introduced.^[3]

A helipad is set on the stern deck. Although there is no hangar, they can supply fuel and electric power to a helicopter on board.^[3]

As a main weapon, a JM61-RFS 20 mm rotary gun system with an optical director was installed on the early ships built under the FY2009 and FY2012. And more powerful Bushmaster II 30 mm chain gun system was installed on the late ships built under the FY2013 and following fiscal years.^[4]

A variant made for the Philippines is known as the Teresa Magbanua-class patrol vessel.^[5]

In service

The 10 Kunigami class ships leading JCG's increased focus on grey-zone challenges along with 2 Hateruma-class patrol vessels has made the base at Ishigaki JCG's largest base, surpassing Yokohama. The ships of FY2012 constitutes the main force of the task force deployed around the Senkaku Islands. And the ships built under the FY2013 and following fiscal years were deployed as replacements of the Shiretoko class.^[2][6][7]

Ships in the class