HSwMS ''Sjöormen'' (Sor), Sw. meaning ''sea serpent'', was the

lead ship The lead ship, name ship, or class leader is the first of a series or class of ships that are all constructed according to the same general design. The term is applicable to naval ships and large civilian vessels. Large ships are very comple ...

of the Swedish 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. Many aircraft carriers and submarines currently use uranium fueled nuclear reactors that can provide propulsio ...

. However, the ships where finally completed with for the time extremely large batteries. The ship was a single-hulled submarine, with 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 ...

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 () is the maritime service branch of the Swedish Armed Forces. It is composed of surface and submarine naval units – the Fleet (), formally sometimes referred to as the Royal Navy () – as well as marine units, the Amph ...

for almost 30 years and was then sold to

Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...

in 1997 together with its four

sister ship A sister ship is a ship of the same Ship class, class or of virtually identical design to another ship. Such vessels share a nearly identical hull and superstructure layout, similar size, and roughly comparable features and equipment. They o ...

Service in Singapore

HSwMS ''Sjöormen'' was renamed RSS ''Centurion'' 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 warfare, maritime Military branch, service branch of the Singapore Armed Forces (SAF) responsible for defending the country against any seaborne threats and as a guarantor of its sea lines of ...

, she was decommissioned on 11 March 2015 and scrapped. Her fin and sail were preserved as a memorial at the Republic of Singapore Navy Museum.

Gallery

File:HMS Sjöormen (Sor) Fo36554.jpg, HSwMS ''Sjöormen'' underway in 1968. File:HMS Sjöormen (Sor) Fo6961.jpg, HSwMS ''Sjöormen'' underway in 1968. File:HMS Sjöormen (Sor) Fo6960A.jpg, HSwMS ''Sjöormen'' underway in 1968. File:HMS Sjöormen (Sor) Fo36557.jpg, HSwMS ''Sjöormen'' underway in 1968. File:HMS Sjöormen (Sor) Fo6959.jpg, HSwMS ''Sjöormen'' underway in 1968. File:US Navy 040609-N-5663H-109 A combined U.S. and Republic of Singapore Navy (RSN) task group steams together at the close of the at-sea portion of the Singapore phase of Cooperation Afloat Readiness and Training (CARAT).jpg, RSS ''Centurion'' leading a combined US and RSN task group during

Cooperation Afloat Readiness and Training The Cooperation Afloat Readiness and Training (CARAT) is a series of annual bilateral military exercises conducted by the United States Pacific Fleet, with several member nations of ASEAN in Southeast Asia. Currently, the navies of Bangladesh, ...

(CARAT) 2004.

References

Sjöormen-class submarines Ships built in Malmö 1967 ships Challenger-class submarines Republic of Singapore Navy {{submarine-stub