HSwMS ''Sjöbjörnen'' (Sbj), Sw. meaning ''sea bear'', was the third ship of the

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

submarine class ''Sjöormen'', project name A11.

Development

The planning of the class included a number of different AIP solutions including

nuclear propulsion Nuclear propulsion includes a wide variety of propulsion methods that use some form of nuclear reaction as their primary power source. The idea of using nuclear material for propulsion dates back to the beginning of the 20th century. In 1903 it was ...

. However, the ships where finally completed with for the time extremely large batteries. The ship was a single-hulled submarine, with the hull shape influenced by the American experimental submarine . The hull was covered with rubber tiles to reduce the acoustic signature (

anechoic tile __NOTOC__ Anechoic tiles are rubber or synthetic polymer tiles containing thousands of tiny voids, applied to the outer hulls of military ships and submarines, as well as anechoic chambers. Their function is twofold: *To absorb the sound waves o ...

s), at this time a pioneering technology. The also pioneered the use of an x-shaped (as opposed to cross-shaped) rudder as a standard (as opposed to experimental) feature.

Service in Sweden

The submarine served in the

Swedish Navy The Swedish Navy ( sv, Svenska marinen) is the naval branch of the Swedish Armed Forces. It is composed of surface and submarine naval units – the Fleet () – as well as marine units, the Amphibious Corps (). In Swedish, vessels o ...

for almost 30 years and was then sold to

Singapore Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, borde ...

in 1997 together with its four sister ships.

Service in Singapore

HSwMS ''Sjöbjörnen'' was renamed RSS ''Challenger'' and Singapore reacquired the boat on 28 May 1999. She was commissioned on 26 June 2004 after a major refit. After 11 years in the

Republic of Singapore Navy The Republic of Singapore Navy (RSN) is the naval service branch of the Singapore Armed Forces (SAF) responsible for defending the country against any sea-borne threats, and the protection of its sea lines of communications, that would comprom ...

, she was decommissioned on 11 March 2015 and scrapped.

Gallery

File:HMS Sjöbjörnen (Sbj) Fo36571.jpg, HSwMS ''Sjöbjörnen'' being launched on 9 January 1968. File:HMS Sjöbjörnen (Sbj) Fo36575.jpg, HSwMS ''Sjöbjörnen'' surfacing in 1968. File:RSS Challenger.jpg, RSS ''Challenger'' undergoing session trials on 23 March 2010.

References

Sjöormen-class submarines Ships built in Malmö 1968 ships Challenger-class submarines Republic of Singapore Navy {{Sweden-stub