The ''Jymy''-class motor torpedo boats (English: "Rumble") or J class was an

Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy over the centuries ** Italians, a Romance ethnic group related to or simply a citizen of the Italian Republic or Italian Kingdom ** Italian language, a Romance languag ...

-designed and built class of motor torpedo boats, seeing service during

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with the

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and later with the

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. The four boats of the J class were built by Cantieri Baglietto in

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, Italy and purchased by the Finns on 5 June 1943. Following World War II, the vessels were rearmed according to the Paris Peace Treaty of 1947, losing their

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such ...

capabilities and given more guns. They were removed from service in 1961.

Design and description

The J class were initially four motor torpedo boats of the Italian . The ''MAS 526'' class were a lengthened version of the preceding with a

displacement Displacement may refer to: Physical sciences Mathematics and physics *Displacement (geometry), is the difference between the final and initial position of a point trajectory (for instance, the center of mass of a moving object). The actual path ...

of , measuring long with a

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of and a draught of . The motor torpedo boats were propelled by two propellers powered by two

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s creating . They had a maximum speed of . The vessels carried of fuel giving them a range of at or at 42 knots. The J class were armed with two

torpedo tube A torpedo tube is a cylindrical device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units (also referred to as torpedo launchers) installed aboa ...

s, one Breda gun and one machine gun.

Vessels of the class

Construction and career

All four vessels were constructed in Italy and served with the

during

. Finland acquired the four motor torpedo boats on 5 June 1943. The Paris Peace Treaty of 1947 was signed following the end of World War II, and Finland was prohibited by the treaty from having torpedo-carrying vessels. The ships were converted into motor gunboats in 1949, in accordance with the treaty. The vessels were rearmed with a gun in addition to the 20 mm gun. Their maximum speed was reduced to and their displacement decreased to . The J-class vessels were stricken from the naval vessel register in 1961.

Citations

References

* * * * * {{WWII Finnish ships Torpedo boats of the Finnish Navy Torpedo boat classes