The ''Ruotsinsalmi''-class minelayers were a two-strong class of

minelayer A minelayer is any warship, submarine, military aircraft or land vehicle deploying explosive mines. Since World War I the term "minelayer" refers specifically to a naval ship used for deploying naval mines. "Mine planting" was the term for ins ...

s in the

Finnish Navy The Finnish Navy ( , ) 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 for "Finnish Navy ship", but ...

. The two ships, comprising and , were constructed in Finland and saw service in the

Winter War The Winter War was a war between the Soviet Union and Finland. It began with a Soviet invasion of Finland on 30 November 1939, three months after the outbreak of World War II, and ended three and a half months later with the Moscow Peac ...

and

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. ''Riihahti'' was sunk in an engagement with Soviet motor torpedo boats on 23 August 1943. ''Ruotsinsalmi'' survived the wars and remained in service in the post war Finnish Navy until being withdrawn in the 1970s.

Design and description

By the late-1930s, the

was focused on defence of the nation and the only ships under construction by Finland were the ''Ruotsinsalmi''-class

s and assorted smaller craft. This was due to the majority of the defence budget being awarded to the

Finnish Army The Finnish Army ( , ) is the army, land forces branch of the Finnish Defence Forces. The Finnish Army is divided into six branches: infantry (which includes armoured units), field artillery, anti-aircraft artillery, Combat engineering, engineer ...

. The ''Ruotsinsalmi''s measured

long overall 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, and is also u ...

with a

beam Beam may refer to: Streams of particles or energy *Light beam, or beam of light, a directional projection of light energy **Laser beam *Radio beam *Particle beam, a stream of charged or neutral particles **Charged particle beam, a spatially lo ...

of and a draught of . They had a

standard displacement The displacement or displacement tonnage of a ship is its weight. As the term indicates, it is measured indirectly, using Archimedes' principle, by first calculating the volume of water displaced by the ship, then converting that value into wei ...

of . The vessels were powered by two Rateau

diesel engine The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...

s turning two shafts creating and giving the minelayers a maximum speed of . They had a complement of 60. The ships were armed with one 50-

calibre In guns, particularly firearms, but not artillery, where a different definition may apply, caliber (or calibre; sometimes abbreviated as "cal") is the specified nominal internal diameter of the gun barrel bore – regardless of how or wher ...

guns, two Madsen anti-aircraft cannon for

anti-aircraft warfare Anti-aircraft warfare (AAW) is the counter to aerial warfare and includes "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It encompasses surface-based, subsurface (Submarine#Armament, submarine-lau ...

. The vessels were also equipped with

mine Mine, mines, miners or mining may refer to: Extraction or digging *Miner, a person engaged in mining or digging *Mining, extraction of mineral resources from the ground through a mine Grammar *Mine, a first-person English possessive pronoun M ...

dropping rails, and could carry about 100 mines. Though not designed for

anti-submarine warfare Anti-submarine warfare (ASW, or in the older form A/S) is a branch of underwater warfare that uses surface warships, aircraft, submarines, or other platforms, to find, track, and deter, damage, or destroy enemy submarines. Such operations ar ...

, the ''Ruotsinsalmi''-class ships mounted two

depth charge A depth charge is an anti-submarine warfare (ASW) weapon designed to destroy submarine A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited ...

racks and two throwers.

Vessels of the class

Construction and career

Both and sister ship were

laid down Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship. Keel laying is one ...

in 1938, launched in 1940 and completed in 1941. The minelayers were active in the

and again in

both times engaged with the

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

. In July 1943, Soviet forces attempted a breakout into the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the ...

from where the Finns had them blockaded via the Seeigel-Rukajärvi mine barrage. There were a number of naval encounters in the Soviet attempt and ''Riihahti'' was sunk on 23 August 1943 in a battle with Soviet motor torpedo boats. ''Ruotsinsalmi'' survived the war and remained in the Finnish Navy even after the terms of the Paris Peace Treaty of 1947 that was signed following the end of World War II restricted the navy's operational capacities. In the post war era, ''Ruotsinsalmi'' was rearmed with two guns and two 20 mm guns while retaining her minelaying capability. Moore and Westerlund & Chumbley claim the vessel was deleted in 1975 and Westerlund states the vessel was stricken in 1977.

Notes

Citations

References

* * * * * * {{WWII Finnish ships Mine warfare vessels of the Finnish Navy Mine warfare vessel classes Ships built in Turku