The Tsurugi class （） is a class of small patrol vessel of the Japan Coast Guard

Japan Coast Guard

The , formerly the Maritime Safety Agency, is the Japanese coast guard. Comprising about 12,000 personnel, it is under the oversight of the Ministry of Land, Infrastructure, Transport and Tourism, and is responsible for the protection the coast-lines of Japan...

 (JCG). The development of this class was one of the earliest attempts of the JCG to deal with spy boats from North Korea

North Korea

The Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...

. In March 1999, the JCG tried to intercept vessels of unknown nationality suspected to be North Korean, but the unknown vessels were too fast, and the Japan Maritime Self-Defense Force

Japan Maritime Self-Defense Force

The , or JMSDF, is the naval branch of the Japan Self-Defense Forces, tasked with the naval defense of Japan. It was formed following the dissolution of the Imperial Japanese Navy after World War II....

 had to be called to intercept the unknown vessels. As a consequence of this failure, JCG realized their need for high speed interceptors.

The Tsurugi class is referred to as High-speed, Special-Purpose Patrol Vessels . Planned as the top-tier of JCG intercept spy boats, this class features very high speed and accurate firepower. Its weaponry includes a JM61 20 mm Gatling gun

M61 Vulcan

The M61 Vulcan is a hydraulically or pneumatically driven, six-barreled, air-cooled, electrically fired Gatling-style rotary cannon which fires 20 mm rounds at an extremely high rate. The M61 and its derivatives have been the principal cannon armament of United States military fixed-wing aircraft...

, and a Remote Firing System consisting of a remote weapon system with a laser-optical fire-control system

Fire-control system

A fire-control system is a number of components working together, usually a gun data computer, a director, and radar, which is designed to assist a weapon system in hitting its target. It performs the same task as a human gunner firing a weapon, but attempts to do so faster and more...

.

In the Battle of Amami-Ōshima, the combination of the 20 mm gun with the RFS proved its worth, but it became clear that its effective range was insufficient against weapons on board the North Korean spy boats such as 9K38 Igla MANPADS and B-10 recoilless rifle

B-10 recoilless rifle

The B-10 recoilless rifle is a Soviet 82 mm smoothbore recoilless rifle. It could be carried on the rear of a BTR-50 armoured personnel carrier. It was a development of the earlier SPG-82, and entered Soviet service during 1954...

. In response, the JCG intends to organize mobile flotillas combining Tsurugi-class vessels with vessels of the Hida class and the Aso class, which have Bofors 40 mm L/70 autocannon

Autocannon

An autocannon or automatic cannon is a rapid-fire projectile weapon firing a shell as opposed to the bullet fired by a machine gun. Autocannons often have a larger caliber than a machine gun . Usually, autocannons are smaller than a field gun or other artillery, and are mechanically loaded for a...

s.

Ships in the class

PS-201 Tsurugi

Commissioned: February 2001

Home port: Sakata, Yamagata

Sakata, Yamagata

is a city located in Yamagata Prefecture, Japan.As of 2006, the city has an estimated population of 116,883 and the population density of 193.92 persons per km². The total area is 602.74 km².-History:The city was founded on April 1, 1933...

PS-202 Hotaka

Commissioned: March 2001

Home port: Maizuru, Kyoto

Maizuru, Kyoto

is a city located in Kyōto, Japan, on an inlet of the Sea of Japan.As of 2008, the city has an estimated population of 89,626 and the density of 264 persons per km². The total area is .The city was founded on May 27, 1943....

PS-203 Norikura

Commissioned: March 2001

Home port: Fushiki, Toyama

Takaoka, Toyama

is a city situated in the northwest of Toyama Prefecture, Japan, and is the central city of its Western District. Takaoka covers the 8th largest surface area in Toyama prefecture and has the second largest population after Toyama City...

PS-204 Kaimon

Commissioned: April 2004

Home port: Naze, Kagoshima

Naze, Kagoshima

Naze was a city located on Amami Ōshima in Kagoshima, Japan.On March 20, 2006 Naze was merged with the town of Kasari, and the village of Sumiyō, both from Ōshima District, to form the new city of Amami....

PS-205 Asama

Commissioned: April 2004

Home port: Hamada, Shimane

Hamada, Shimane

is a city located in Shimane, Japan. It is the third largest city in the prefecture and is located at the south-western end of the prefecture. It is a coastal city on the Sea of Japan and possesses beautiful white-sand beaches, which make the city a popular destination for local tourists in the...

PS-206 Howo

Commissioned: January 2005

Home port: Nagasaki

Nagasaki

is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. Nagasaki was founded by the Portuguese in the second half of the 16th century on the site of a small fishing village, formerly part of Nishisonogi District...