Republic of Singapore Navy Crest
Sources: Wikimedia Commons

The genesis of the Republic of Singapore Navy's (RSN) submarine squadron began in the late 1980s, when eight RSN officers attended a three-week submarine operating course in Eckernode, Germany.[16] In the 1990s, RSN had a similar program with Sweden, which subsequently resulted in the acquisition of submarines from the Swedish shipyard Kockums.[1] Initially, in 1995, Singapore announced that RSN would acquire a single 'low-cost second-hand submarine' (Sjöormen class) from Sweden for evaluation purposes as part of the Riken Project. That same year, Singaporean defense minister Dr. Tony Tan Keng Yam noted that the procurement of this boat would enable RSN to "learn more about submarine operations and how they add to the capabilities of the fleet."[2] Although this submarine was launched in September 1997, the boat returned to Singapore only in 2004. This submarine was based in Sweden for training purposes, and to evaluate the usefulness of submarines for Singapore's defense.[3]

In July 1997, Singapore announced that it would acquire three more submarines from Sweden, which would form (along with RSS Challenger), the 171 Squadron: RSS Centurion (ex-Sjöormen); RSS Conqueror (ex-Sjölejonet); and RSS Chieftain (ex-Sjohunden).[4] The Royal Swedish Navy originally operated these boats in the 1970s. In Singapore, these three boats were re-commissioned by the RMN as follows: Conqueror in July 2000; Chieftain in August 2002; and Centurion in June 2004.[5]

Rather than buying more technically advanced vessels to replace the Challenger-class (Sjöormen), Singapore instead bought Västergotland-class submarines. In the late 1980s Sweden commissioned four Västergotland-class submarines (Västergötland, November 1987; Hälsingland, October 1988; Södermanland, April 1989; and Östergötland, January 1990). Due to budgetary constraints, however, Västergötland and Hälsingland faced early retirement, while Södermanland and Östergötland were reconfigured as Södermanland-class boats. Improvements included the insertion of a 12m plug for AIP; a pressurized diver's lock-out to facilitate Special Forces operations; and a new climate control system for operations in warmer waters.

In November 2005, Singapore signed a contract with Kockums AB to purchase the two retired Västergotland-class submarines (rechristened Archer and Swordsmen). However, they were first to be modernized to Södermanland-class standards. As both the classes-Sjöormen and Västergotland-are of Swedish origin, RSN should be able to "benefit from the synergies both in crew training and logistics support."[6]

Singapore's decision to procure the Västergotland/Södermanland class, instead of the more advanced Gotland class, surprised several security analysts and policymakers in the region. Jane's speculates that the Singaporean government consciously decided not to introduce new advanced military equipment that could affect the regional military balance.[8] Singapore's Submarine Squadron is more advanced-in terms of technology and operational experience-than Indonesia's two Type 209 boats and Vietnam's two midget submarines. However, Malaysia is in the process of inducting two Scorpion-class submarines from France, and Vietnam plans to acquire six Russian Kilo-class submarines.

Sources:
[1] Republic of Singapore Navy, "Backpaddle," Navy News, Issue 3, 2009, p. 13.
[2] For information on Kockums, refer to: "Sweden Export Behavior," NTI Submarine Proliferation Database, www.nti.org; and Kockums Submarines & Systems, www.kockums.se.
[3] "Singapore Buys Swedish Submarine," Jane's Navy International, Volume 100, Issue 06, 1 December 1995.
[4] Singapore Ministry of Defence, "Keynote Address by Dr. Tony Tan Keng Yam, Deputy Prime Minister and Minister for Defence, for the Launch of RSS Challenger in Sweden on 26 Sep 97," News and Events, 27 September 1997, www.mindef.gov.sg.
[5] Keith Jacobs, "Naval Procurement Programs in Southeast Asia," Naval Forces, Vol. 23, Issue 2, April 2002.
[6] "Singapore Submarine Forces," Jane's Underwater Warfare Systems, 2009.
[7] "The Republic of Singapore Navy –Mission, Organizational Structure and Naval Bases," Naval Forces, p. 12.
[8] "Singapore Submarine Forces," Jane's Underwater Warfare Systems, 2009.