''Skjold''-class corvettes (skjold means "shield" in

Norwegian Norwegian, Norwayan, or Norsk may refer to: *Something of, from, or related to Norway, a country in northwestern Europe *Norwegians, both a nation and an ethnic group native to Norway *Demographics of Norway *The Norwegian language, including the ...

) are a class of six light, superfast, stealth missile

corvette A corvette is a small warship. It is traditionally the smallest class of vessel considered to be a proper (or " rated") warship. The warship class above the corvette is that of the frigate, while the class below was historically that of the slo ...

s in service with the

Royal Norwegian Navy The Royal Norwegian Navy ( no, Sjøforsvaret, , Sea defence) is the branch of the Norwegian Armed Forces responsible for naval operations of Norway. , the Royal Norwegian Navy consists of approximately 3,700 personnel (9,450 in mobilized state, 3 ...

. The boats were formerly classed as MTBs ( motor torpedo boats) but, from 2009, the Royal Norwegian Navy has described them as corvettes (''korvett'') because their

seaworthiness Seakeeping ability or seaworthiness is a measure of how well-suited a watercraft is to conditions when underway. A ship or boat which has good seakeeping ability is said to be very seaworthy and is able to operate effectively even in high sea stat ...

is seen as comparable to corvettes, and because they do not carry torpedoes. They were built at the

Umoe Mandal Umoe Mandal AS is a shipbuilding company in the Ulltveit-Moe Group. Their shipyards are based at Mandal in Norway. Founded in 1989 as Kværner Båtservice, later Kværner Mandal, and known as Umoe Mandal since 2000, the company specialises in hig ...

yard. With a maximum speed of , the ''Skjold''-class corvettes were the fastest combat ships afloat at the time of their introduction.

Development and production

The ''Skjold''-class vessels began with the development of the Royal Norwegian Navy's "Project SMP 6081", and the first preproduction version was ordered on 30 August 1996. The first ship of its class, P960, was launched on 22 September 1998 and commissioned 17 April 1999. A Norwegian Parliamentary White Paper of 2001 recommended building five additional boats, and this was agreed to in 2002. Six ''Skjold''-class vessels replaced the Royal Norwegian Navy's previous fourteen s.

Design

The ''Skjold'' design is a surface effect craft, constructed of

glass fibre Glass fiber ( or glass fibre) is a material consisting of numerous extremely fine fibers of glass. Glassmakers throughout history have experimented with glass fibers, but mass manufacture of glass fiber was only made possible with the inventio ...

/carbon composite materials. Buoyancy is augmented underway by a fan-blown skirted compartment between the two rigid catamaran-type hulls. This provides an alternative solution to the planing hull/vee hull compromise: the air cushion reduces wave slam at high speeds while presenting a low-drag flat planing profile at the waterline. To ensure stealth capabilities,

anechoic An anechoic chamber (''an-echoic'' meaning "non-reflective") is a room designed to stop reflections of either sound or electromagnetic waves. They are also often isolated from energy entering from their surroundings. This combination means t ...

coatings of

radar absorbent material In materials science, radiation-absorbent material, usually known as RAM, is a material which has been specially designed and shaped to absorb incident RF radiation (also known as non-ionising radiation), as effectively as possible, from as m ...

s (RAM) have been used in the load-bearing structures over large areas of the ship. This strategy leads to significant weight saving compared to the conventional construction technique of applying RAM cladding to the external surfaces. The ship's profile has a faceted appearance with no right angle structures and few orientations of reflective panels. Doors and hatches are flush with the surfaces and the windows are flush without visible

coaming Coaming is any vertical surface on a ship designed to deflect or prevent entry of water. It usually consists of a raised section of deck plating around an opening, such as a cargo hatch. Coamings also provide a frame onto which to fit a hatch cove ...

(edge of window aperture) and are fitted with radar reflective screens. The vessels are additionally protected by the Rheinmetall MASS sensor / decoy system. Norwegian Navy Patrol boat Storm

The final design was changed compared to the prototype ''Skjold'', which itself was rebuilt to the new specifications. Most notably, the vessels use 4

gas turbines A gas turbine, also called a combustion turbine, is a type of continuous flow internal combustion engine. The main parts common to all gas turbine engines form the power-producing part (known as the gas generator or core) and are, in the directi ...

combined by

Renk The RENK Group (stylised as RENK Group) is a German company and ranked among the top ten companies in the German defense industry in terms of sales in 2010. Its main production sites are located in Augsburg, Rheine, Hanover and Winterthur (Swit ...

COGAG Combined gas turbine and gas turbine (COGAG) is a type of propulsion system for ships using two gas turbines connected to a single propeller shaft. A gearbox and clutches allow either of the turbines to drive the shaft or both of them combined. ...

gear units built in a lightweight design. The smaller gas turbines rated 2,000 kW turbines are used for cruising speed. For sprint speed a second, larger gas turbine is combined providing a total of 6,000 kW to the waterjet on each shaft line. Two MTU 123 cruise diesel propulsion units used previously at loiter speeds were removed. The foredeck was strengthened to accommodate the addition of a 76 mm Otobreda Super Rapid gun. The hull material was produced by a different method to improve strength and minimize vulnerability to fire. The bridge saw some changes, including an upgrade to six weapon systems control consoles. In 2020, the Norwegian Government decided to further upgrade the Skjold-class vessels, partially to compensate for the loss of the frigate

Helge Ingstad Helge Marcus Ingstad (30 December 1899 – 29 March 2001) was a Norwegian explorer. In 1960, after mapping some Norse settlements, Ingstad and his wife archaeologist Anne Stine Ingstad found remnants of a Viking settlement in L'Anse aux Meadows ...

. The upgrades would take place between 2020 and 2024, permitting the Skjold-class to remain up-to-date through to 2030 when replacement vessels were envisaged under terms of the Government's defence plan.

US Navy

Norwegian missile patrol craft KNM Skjold (P 690) stern view

The

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage o ...

and Coast Guard expressed interest in the design and leased the P960 for a period of one year, from 2001 until 2002. During that time it was operated by a 14-man Norwegian crew out of

Naval Amphibious Base Little Creek A navy, naval force, or maritime force is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake-borne, riverine, littoral, or ocean-borne combat operations and related functions. It includ ...

Vessels

References

* Saunders, Stephen "Jane's Fighting Ships 2003–2004" .

External links

* Leo Lazauskas (2008
''Performance characteristics of a 260t displacement SES''
Dept. Applied Mathematics Report, The University of Adelaide, 19 February 2008.
''Norwegian Skjold class corvettes storm and steil in Plymouth Sound''
9 July 2015. {{DEFAULTSORT:Skjold Class Patrol Boat Missile boats of the Royal Norwegian Navy Patrol vessels of Norway Military catamarans Stealth ships Corvette classes Patrol boat classes