Spica-class torpedo boat (Sweden)

The Spica class was a class of six fast torpedo boats built for the Swedish Navy in the 1960s and decommissioned in the late 1980s. One ship, HSWMS Spica (T121), is preserved as a museum ship in Stockholm, Sweden.

History
The ships were ordered in 1961 as part of a re-armament programme for defending Sweden's coastline. Tenders were sought from various European boat builders in the United Kingdom, Norway and Germany including Lurssen who offered the new Jaguar-class design. The Swedes ended up designing a bespoke vessel which became the template for subsequent Swedish fast attack craft.

Design
The hull was made of steel, unlike some other contemporary designs which used plywood. The boats were fitted with a NBC support system where the hull could be closed down in the event of having to operate in a nuclear fall-out area.

Machinery
The machinery consisted of three shafts powered by British built, Bristol Proteus gas turbines. Three MTU gas turbines were also installed as auxiliary generators

Armament
The torpedo armament consisted of six 533 mm torpedo tubes which were positioned at an angle. Wire guided torpedoes were used. The gun armament consisted of a single Bofors 57 mm gun, which was capable of firing 200 rounds per minute over an effective range of 8500 m. The gun could engage both surface and airborne targets. There were also six 57 mm and four 103 mm rocket launchers capable of firing chaff, infrared countermeasures and illuminating projectiles (starshell). The torpedo boats had a scanning and a fire control radar with a basic fire control computer. There were plans to replace the torpedo tubes with anti-ship missiles in the 1980s but these plans were cancelled.

Ships
Twelve ships of a missile boat variant were built between 1971 and 1975 as the (Spica II).