The Visby Class of stealth corvettes is being built for the Swedish Navy by the Swedish company Kockums (a subsidiary of ThyssenKrupp Marine Systems of Germany). Visby is the first operational stealth ship in the world. The first ship of the new stealth corvette class is named after the main city on the island of Gotland, Visby.
Designed specifically to minimize Radar Cross Section ( RCS ), the Visby is made entirely from carbon fiber and has the stealth technology specific angular shape. The material dramatically reduces the structural weight (typically 50% of a conventional steel hull). This results in a higher payload carrying capability, higher speed or longer range.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 have been reduced to a minimum. In fact the Visby has a detection range of about 15 km, depending on the sea. In rough sea detection range falls to about 13 kilometers, and in calm sea it can reach 22. If, in addition, jamming equipment is used, detection range falls to about 8 kilometers in rough sea. In naval terms, that is excellent.
The Visby class stealth corvettes will fulfill the Mine Countermeasures and Anti-Submarine Warfare roles, as well as attack and anti-surface roles. All missions are supported by CETRIS – the real-time command, control, communication, intelligence and interoperability system (C4I2). The system is modular and open, and allows for integration of future technologies, without expensive changes.
The combined Diesel and Gas ( CODAG ) turbines allow for a maximum speed of 35 knots. Other features include the capability for a helicopter to land and refuel on the upper deck. Every feature that need not necessarily be located outside the hull has been built in or concealed under specially designed hatches. The gas turbine exhausts have been concealed in hidden outlets close to the water surface at the stern of the vessel.
Construction of this amazing vessel started in 1996 at Kockums’ Kalrskrona yard. Five Visby class stealth corvettes have been launched so far. The first, Visby, was launched in June 2000, followed by Helsingborg in June 2003. December 2004 marked the launch of Harnosand, Nykoping followed in August 2005 and Karlstad was last exactly one year later, in August 2006. A sixth vessel was canceled. The Swedish Defence Material Administration received the first two ships in 2006 ( K31 Visby and K32 Helsingborg – seen in the picture above), and the rest are to be delivered by the end of this year.
Visby Class Corvettes Specifications
Length Between Perpendiculars: 61.5m
Displacement when Fully Equipped: 600t
2 KaMeWa Waterjets powered by:
High-Speed Machinery Four gas turbines – total 16,000kW
Low-Speed Machinery Two diesel engines – total 2.600kW
Generators: Three – total 810kW
Sea Giraffe ABM 3D surveillance Radar
Saab Ceros 200 Fire control radar system
Condor CS-3701 Tactical Radar Surveillance System
Towed array sonar system
Bofors 57 mm/70 SAK Mk3
8 × RBS15 Mk2 AShM
8 x Umkhonto surface-to-air missile
4 × 400 mm tubes for Type 43/45 torpedoes
4 x MASS Countermeasure launchers mines prepared for the installation of heavy Torpedoes