The Kuha-class minesweepers ( en, Zander) is a series of six inshore

minesweeper A minesweeper is a small warship designed to remove or detonate naval mines. Using various mechanisms intended to counter the threat posed by naval mines, minesweepers keep waterways clear for safe shipping. History The earliest known usage of ...

s of the

Finnish Navy The Finnish Navy ( fi, Merivoimat, sv, Marinen) is one of the branches of the Finnish Defence Forces. The navy employs 2,300 people and about 4,300 conscripts are trained each year. Finnish Navy vessels are given the ship prefix "FNS", short f ...

. The ships were constructed in 1974–1975. All the vessels of the class were modified and modernized in the late 1990s, including a lengthening of the hull. Two of the class were withdrawn from service in 2012. The rest of the class will be retired with the entry into service of the s.

Description

Designed in the 1970s, the hulls of the

s are constructed from glass-reinforced plastic. The Kuha-class minesweepers initially measured

long overall __NOTOC__ Length overall (LOA, o/a, o.a. or oa) is the maximum length of a vessel's hull measured parallel to the waterline. This length is important while docking the ship. It is the most commonly used way of expressing the size of a ship, an ...

with a beam of and a draught of . They had a fully loaded displacement of . The vessels were lengthened during modernisation between 1997 and 2000, ending up long overall with an increased fully load displacement of . The Kuha class are powered by two

Cummins Cummins Inc. is an American multinational corporation that designs, manufactures, and distributes engines, filtration, and power generation products. Cummins also services engines and related equipment, including fuel systems, controls, air ...

NT-380M

diesel engine The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-ca ...

s using hydrostatic transmission to turn one shaft and two

controllable pitch propeller In marine propulsion, a variable-pitch propeller is a type of propeller with blades that can be rotated around their long axis to change the blade pitch. Reversible propellers—those where the pitch can be set to negative values—can al ...

s, creating . The engines are flexibly mounted and they have active

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally air or water). On an aircraft the rudder is used primarily to counter adve ...

s. The vessels have a maximum speed of . The Kuha class have a complement of either 2 or 3 officers and 12

enlisted Enlisted may refer to: * Enlisted rank An enlisted rank (also known as an enlisted grade or enlisted rate) is, in some armed services, any rank below that of a commissioned officer. The term can be inclusive of non-commissioned officers or ...

. The ships had two different armament types to begin with, initially armed with either two single guns or two ZU /60 calibre guns mounted in a single

gun turret A gun turret (or simply turret) is a mounting platform from which weapons can be fired that affords protection, visibility and ability to turn and aim. A modern gun turret is generally a rotatable weapon mount that houses the crew or mechani ...

with an additional 20 mm gun. The armament was later made uniform throughout the class, with the twin-mounted 23 mm guns augmented with a machine gun. For minesweeping duties, the Kuha class are equipped with equipment to deal with magnetic, acoustic and pressure mines capable of towing a Type F-82 electrode sweep. The minesweepers have Reson Seabat 6012 mine avoidance

sonar Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on o ...

, Patria Finavitec SONAC HF minehunting sonar and

Racal Decca The Decca Radar company was a British manufacturer of radar systems. There were originally two divisions, Marine and Heavy Radar, with separate product lines. The latter was sold to Plessey in 1965, and the term "Decca Radar" normally refers to ...

radar Radar is a detection system that uses radio waves to determine the distance ('' ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, we ...

. The Kuha class were also capable of remote operating a drone minesweeper, which were put in operation beginning in 1983.

Vessels of the class

Construction and career

Due to limitations set by treaties following the end of

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

, the

was limited in the number and size of ships, along with the number of sailors the Finnish Navy was allowed to employ. Therefore, during the Cold War, the Finnish Navy was confined to building small, coastal defence ships, primarily minesweepers and

missile boat A missile boat or missile cutter is a small, fast warship armed with anti-ship missiles. Being smaller than other warships such as destroyers and frigates, missile boats are popular with nations interested in forming a navy at lower cost. They a ...

s. Fourteen hulls of the Kuha class were ordered in 1972. The last eight were cancelled, with only the first six hulls beginning construction in 1974. Built by Oy Laivateollisuus Ab,

Turku Turku ( ; ; sv, Åbo, ) is a city and former capital on the southwest coast of Finland at the mouth of the Aura River, in the region of Finland Proper (''Varsinais-Suomi'') and the former Turku and Pori Province (''Turun ja Porin lääni''; ...

Finland Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...

, the six ships of the class entered service in 1974–1975. Beginning in 1983, they worked in conjunction with the drone minesweepers, which could either be unmanned or manned. The vessels underwent modernisation at Tyovene Shipyard in

Uusikaupunki Uusikaupunki (; sv, Nystad, ) is a town and municipality of Finland. It is located in the Southwest Finland region, northwest of Turku and south of Pori. The municipality has a population of () and covers an area of of which is inland wate ...

, Finland were they were lengthened to accommodate new minesweeping control systems and new magnetic and acoustic sweeps. ''Kuha 21'' completed its refit on 22 December 1997, ''Kuha 23'' on 30 August 1998, ''Kuha 24'' on 13 November 1998 and ''Kuha 26'' on 30 May 2000. ''Kuha 22'' and ''Kuha 25'' were withdrawn from service in 2012. The rest of the Kuha class will be retired when the s enter active service.

Citations

References

* * * * {{Active ships of the Finnish Navy Ships of the Finnish Navy Minesweepers of the Finnish Navy Mine warfare vessel classes Ships built in Turku