Singapore: State of Submarine Forces in ASEAN 2023 – 3

The third ASEAN country submarine force in my series concerns Singapore.

4 in commission, 3 pre-commission, 1 in production

 

Challenger-class (ex-Sjoormen A11) 

5 boats: 2 active, 2 retired, 1 acquired for spares

Displacement 1,200 tonne

Acquired 1995

Delivered by 2002

Challenger-class image: courtesy Wikipedia/Erik Sevilla Estrada
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Archer-class (ex-Vastergotland A17) 
2 boats, in commission
Displacement 1,400 tonnes
Acquired 2005
Delivered by 2010

RSS Archer image: courtesy Seaforces.org/Kockums
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Invincible-class (Type 218SG) 
3 delivered, 1 in production

Displacement 2,200 tonnes

Ordered 2014

To be delivered from 2023-2026

Invincible-class image: courtesy @WarshipCam

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 The history of the Republic of Singapore Navy’s (RSN) submarine service is a clear demonstration of what Dr. Tim Huxley, in his book Defending the Lion City: The Armed Forces of Singapore (2000) referred to as defence capabilities creep - in that every generational step of a weapons system adds new capabilities to Singapore’s Armed Forces. 

In the case of Singapore’s submarine service, its humble beginnings started when Singapore purchased 30 year old Sjöormen class A11 submarines in 1995 from Kockums’ used submarine pier.
 

All five boats of the retired Sjöormen class were purchased, with the last boat, HSwMS Sjöhästen, cannibalised for spare parts for her four sisters. After modernisation and tropicalisation, the four boats of the Challenger-class entered RSN service by 2002. Two boats (RSS Challenger and RSS Centurion) were decommissioned in 2015. RSS Conqueror and RSS Chieftain remain in service today, though both boats are over 50 years old now. In the 20 years that they’ve served in the RSN, the Challengers set the foundations for Singapore’s submarine operations. By 2019 two RSN submarine officers were “Perisher” graduates.
 

Following on from the Challenger-class, in 2005 Singapore acquired the two remaining Västergötland class submarines, which were placed in Swedish naval reserve in the early 2000s, while their two sister boats were upgraded with AIP modules to become the Södermanland-class (HSwMS Södermanland is about to undergo a second life extension, and remain in service to 2028).

 

RSS Archer (ex-HSwMS Hälsingland, launched 1987) and RSS Swordsman (ex-HSwMS Västergötland, launched 1986) received an extensive refit similar to the Södermanlands, including AIP. The Archers also received tropicalization, air conditioning, a Singapore-developed flank sonar array, and were commissioned into the RSN in 2011 and 2013.

 

The Challengers are a traditional SSKs (though one of the first with a teardrop hull shape) with limited range and the need to frequently snort. In contrast the Archers were refitted with Kockums’ Stirling AIP hull sections, which greatly extended their fully submerged endurance. The Archers also have a pressurized diver’s lockout (part of the 12m AIP module insert) a first on an RSN submarine. It is likely that the Archers have double the endurance of the Challengers, and are frequent visitors to the Andamans for training and exercises with the Indian Navy.

 

In 2013-2014 Singapore held a submarine contest between TKMS and Naval Group. Also see Submarine Matters on this. TKMS was selected to supply two Type 218SG submarines for US$1.36 billion, with a follow-on order placed in 2017 for two additional boats. The first in class, RSS Invincible, was launched by TKMS in Kiel in February 2019, but has remained in the German city for shakedown trials and training, and is slated for delivery to Singapore in 2023. The second and third boats were launched together in December 2022. The second boat of the class, RSS Impeccable, is on its way to Singapore, and should make an appearance on Singapore’s National Day Parade on August 9, 2023.

 

The Invincible class will replace both the Challenger class and Archer class, so it is assumed the RSN will keep its submarine fleet at four boats. The Invincibles “can stay submerged 50% longer than the Archer-class”. They have advanced automation plus a high level of situational awareness, with expanded flank arrays and towed array sonar. The Invincibles also have a bigger payload capacity (including more torpedoes and other weapons) than the Archers, This may include a submarine launched version of the locally developed (with some Israeli assistance) Blue Spear anti ship cruise missile. 

 

Blue Spear, an anti-ship/land attack cruise missile, has been recently confirmed to replace Harpoon in the ASM role for Singapore’s six Formidable-class frigates. Blue Spears will also likely arm the RSN’s six upcoming, larger, Multi-Role Combat Vessels (MRCVs).

 

Singapore’s maritime security had a major revamp in the late 2010s, resulting in the division of the ‘fleet’ into two commands in 2020. Fleet Command contains four Flotillas with Frigates, Missile Corvettes, LSTs and Submarines. While Maritime Security Command (MARSOC)  contains Littoral Mission Vessels, Maritime Security & Response Vessels, Force Protection and UUVs.

 

What is clear is that this fleet division created two commands with separate primary tasks, with the Fleet tasked with power projection and ‘outside littoral boundary’ missions, like patrolling SLOCs. 

MARSOC is focused on the ‘near shore’ - Singapore’s territorial waters, undersea cables/pipes and near sea lanes such as the Malacca Straits, with unmanned vessels providing port security and infrastructure protection, including counter naval mine warfare and seabed inspection.

Singapore has a neutral defence policy. Singapore and China are establishing a secure defence telephone line after signing an MOU on June 1, 2023.  

Shawn Chung
June 1, 2023