Visby Class

Visby Class Stealth Missile Corvette
Visby Class Stealth Missile Corvette
Career
Nationality:	Skandinavia
Operated by:	Skandinavia
Builder:	Kockums NAtech Marine(since 2011)
Ordered:	First of class: October 2001
Launched:	First of class: June 2003
Commissioned:	First of class: January 2005
Status:	In Service
General characteristics
Displacement:	640 tonnes
Length:	72.7 m
Beam:	10.4 m
Draft:	2.4 m
Power:	24MW
Propulsion:	NAtech/Volvo COFCAG (multi-gas turbine and fuel cell propulsion system) with two NAtech Marine hydrojets
Speed:	39 knots
Maximum speed:	51 knots
Range:	3,100 nautical miles at 39 knots
Complement:	43
Armament:	Sensors 1 x TERMA C-Flex Combat Management System 1 x Saab 9LV FCS Fire Control System 1 x Saab EOS 500 Electro Optical Fire Control 1 x TERMA SCANTER 4100 Surveillance Radar 1 x Kongsberg C-Scope Sonar System Electronic warfare 1 x TERMA TV-112 tactical radar surveillance system Decoys 1 x TERMA DL-22T Multi Ammunition Decoy System 1 x TERMA Loki torpedo countermeasure Armament 1 × 8 cell Vertical Launching System w/ 16 Meteor SAM missile 12 × RBS15 Mk3 SSMs 4 × torpedo tubes for Torpedo 62 Depth charges 1 × 57 mm BOFORS Mk.3 1 x 30 mm Kongsberg Sea Protector CIWS
Aircraft carried:	1 x AS532 SC Cougar ASUW / ASW 1 UAV

Visby Class Stealth Missile Corvette were designed to be the main Sjøforsvaret's element for coastal water operations. The ship's design heavily emphasizes low visibility, radar cross-section and infrared signature as well as high speed and maneuverability. The first ship in the class is named after Visby, the main city on the island of Gotland. In 2020 there are 20 ships in service and 2 more under construction. The first 12 units were built by Kockums, while the following ones were built by NAtech Marine after acquiring the surface ship business of the former Kockums.

Design

The design of the Visby aims to minimise the optical and infrared signature, above water acoustic and hydroacoustic signature, underwater electrical potential and magnetic signature, pressure signature, radar cross section and actively emitted signals. A stealth corvette of the Visby Class has a detection range of 10km in rough seas and 18km in calm sea without jamming. In a jammed environment, the Visby would be detected at a range of 6km in rough sea and 9km in calm sea.

The hull material is a sandwich construction comprising a PVC core with a carbon fibre and vinyl laminate. The material provides high strength and rigidity, low weight, good shock resistance and very low radar and magnetic signature.

Command & Control

Visby Class were the first Sjøforsvaret's ships to be equiped with TERMA C-Flex Combat Management System. C-Flex is basen on open system architecture and is able to integrate the Saab 9LV FCS Fire Control System and Saab EOS 500 Electro Optical Fire Control. The system is completed with a TERMA SCANTER 4100 Surveillance Radar and a modified Kongsberg C-Scope Sonar System.

The communications system has a high-capacity digital communications switch, developed by TERMA, which interconnects the voice and data communications channels. The system provides internal communications or open conference lines and access to external communications with various radio links and land-based networks.

Power generation & propulsion

FLOSK chose to equip the ship with a mixed multi-gas turbine and fuel cell propulsion system (COFCAG) developed jointly by NAtech and Volvo Aero. Main fuel for which the system has been designed is hydrogen, but the system can also work with natural gas, methane and other gases, although with a lower energy efficiency. At low speed and during maneuvers the system uses the power delivered by the fuel cells, using the gas turbine system to achieve higher speeds. In addition, the system reuses the exhaust gases to turbocharge the turbine and for the ship's heating systems, which considerably reduces the ship's thermal footprint and finally the remaining gases are expelled from the stern. Power plant of the ship was designed taking into account the current needs of energy for propulsion and other systems on board, so it was possible to assume an increase in power required if new equipment or systems were installed in the future.

The propulsion system is fully electrical with two NAtech Marine hydrojets mounted externally to the main hull. The electricity for the motors is supplied by the power system. The ship has rudders and bowthrusters for harbour manoeuvring.

Electronic systems

One of the main design premises was the need to mount Skandinavian made electronic systems in order to full integration with other Forsvaret systems and satellite net.

Sensors

• 1 x TERMA C-Flex Combat Management System
• 1 x Saab 9LV FCS Fire Control System
• 1 x Saab EOS 500 Electro Optical Fire Control
• 1 x TERMA SCANTER 4100 Surveillance Radar
• 1 x Kongsberg C-Scope Sonar System

Electronic warfare

• 1 x TERMA TV-112 tactical radar surveillance system

Decoys

• 1 x TERMA DL-22T Multi Ammunition Decoy System
• 1 x TERMA Loki torpedo countermeasure

Armament

• 1 × 8 cell Vertical Launching System w/ 16 Meteor SAM missile
• 12 RBS15 Mk3 SSMs
• 4 torpedo tubes for Torpedo 62
• 1 ASW 127mm rocket-powered grenade launchers and depth charges
• 1 57 mm BOFORS Mk.3
• 1 x 30 mm Kongsberg Sea Protector CIWS

Air wing

1 x AS532 SC Cougar ASUW

List of ships

#	Name	Ordered	Launched	Commissioned
K-30	KSS Visby	October 2001	June 2003	January 2005
K-31	KSS Helsingborg	October 2001	June 2003	November 2005
K-32	KSS Härnösand	October 2001	June 2003	November 2005
K-33	KSS Nyköping	October 2001	June 2003	January 2006
K-34	KSS Karlstad	October 2001	March 2004	June 2006
K-35	KSS Uddevalla	October 2001	March 2004	June 2006
K-36	KSS Trollhättan	October 2001	March 2004	November 2006
K-37	KSS Borlänge	October 2001	August 2005	May 2007
K-38	KSS Kälarne	October 2001	August 2005	October 2007
K-39	KSS Gällivare	October 2001	August 2005	January 2008
K-40	KSS Umeå	January 2012	March 2012	November 2013
K-41	KSS Särna	January 2012	March 2012	November 2013
K-42	KSS Ljusdal	January 2012	January 2013	March 2014
K-43	KSS Gävle	January 2012	January 2013	March 2014
K-44	KSS Arvika	January 2012	January 2014	March 2015
K-45	KSS Kristinehamn	January 2012	January 2014	March 2015
K-46	KSS Katrineholm	January 2012	January 2015	February 2016
K-47	KSS Skara	January 2012	January 2015	February 2016
K-48	KSS Nybro	January 2012	December 2015	November 2016
K-49	KSS Kungälv	May 2015	June 2016	September 2017
K-50	KSS Strömstad	May 2015	August 2018	October 2020
K-51	KSS Sölverborg	May 2015	August 2018	January 2021