February 22, 2019

What Singapore's Type 218SG Submarines Might Be Used For (Part 2)

The most official 18 February 2019 indicator of what Singapore's new Invincible class Type 218SG submarine will be used for is less controversial non-state threats: terrorists, pirates, smugglers of arms, drugs and of people. 

But much more should be added (below) including Singaporean submarines defending against and monitoring Chinese ship, submarine and land targets. 

The emphasis given to AIP in Singapore's current 2 x Archer class (Stirling AIP) and 4 future 218SGs (fuel cell AIP) suggest short to medium range missions will be common. This is because AIP is heavy and of diminishing utlilty on longer range missions. 


The 218SG's Atlas Elektronik combat system, with some US add-ons, will retain many existing capabilities and add new ones. Many missions around Singapore Island (map below) and the Malacca Strait will be on AIP (for around 2 weeks) only. Much of this short range work is (will be) for electronic warfare (eg. signals interception). Such interception "targets" can more publically include the non-state actors (eg. detecting short range terrorist/pirate/smuggler radio signals).

Once a submarine senses a target a submarines weapons are too heavy and expensive (more than 
US$1 million per torpedo or missile) to destroy a small boat. Also you'd blow up people who may only be suspects and blow up all evidence! Instead a submarine (using tethered signal buoy beaming to satellite?) may alert a Singapore Police Coast Guard boat or Navy patrol vessel (maybe launching a smaller rigid hulled boat) to deal with the target boat more "gently".

With only 28 officers-sailors needing accommodation on 218SGs, on special missions there may be space for:

-  around 6 intercept operators/linguists with 6 work stations 
-  around 10 divers-special forces and their equipment (one mission fighting terrorists).

Networked with Singapore's submarines in combatting and monitoring threats includes other Singaporean, US and other allied platforms. Platforms include land based or connected sensors, seabed (long range SOSUS) broader ocean sensors and shorter range (RAP/FDS) sensors strung across the Malacca Strait seabed and nodes on/near Singapore main island and islets. On seabed sensors see https://gentleseas.blogspot.com/2019/01/possible-sosus-rapfds-arrays-western.html .

Possibly networked with and informing subs are human intelligence/police/border/customs, overt press, patrol boats, frigates, LCSs, aircraft/UAVs, land-based radar and intercept stations and satellites. 


All these networked sensors can help cue submarines to tail Chinese submarines on surfaced "innocent passage" through the Malacca Strait and more so Chinese subs who decide to pass through submerged. 

SSKs like the 218SG are too slow to shadow Chinese SSNs and SSBNs. But (with Japanese submarines doing the northern leg shadow) 218SGs could do the southern leg shadow of Chinese Song and AIP Yuan class SSKs.  

Only at long ranges into the Pacific (including South China Sea) and Indian Ocean would Singapore's submarines be a little more autonomous of all this network help. Looking at Germany's Type 212A as a minimum, the 218SG may have a range of around 8,000nm at around 4 to 8 knots combined snorting and surfaced. Such a range would allow a 218SG to:

-  patrol oil strategic lines of communication (SLOCs) between the mid-Indian Ocean
    (eg. Diego Garcia or India's east coast bases) and Singapore.
-   Singapore to Taiwan and return (maybe keeping an eye on the southern China
    coast) using aerials extended from the fin/sail, tethered buoys or work-to-submarine UUVs.

Singapore's submarines (as with the surface navy) all the way to the Persian Gulf oil area, can contribute to longer range protection of the oil/gas/chemical tanker route. This includes tankers eastwards across the Indian Ocean to Singapore's refinery/chemical facilities.

Map of Singapore. Consisting of one main island and 62 islets. Ongoing land reclamation projects have increased Singapore's land area from 582 km2 in the 1960s to 724.2 km2 in 2018. This geography provides many places for 218SG to sit waiting on the seabed, between islets while monitoring many things. (Map courtesy Geology(dot)com)

Broader map of the Strait of Malacca/Malacca Strait (of great strategic and economic value) and the much smaller Strait of Singapore(Map courtesy welt-atlas).


Another way to estimate what the 218SG may be used for is to look at the Combat System - Weapons suite.

Singapore does not appear to be using the submarine weapons of its main ally, the US, other than possibly the US made Harpoon anti-ship and land attack missile. Singapore’s Air Force and Navy use the Harpoon. In the submarine launch mode the Harpoon is called UGM-84 with a range of up to 140 km (75 nm) against ship and land targets.

Other than the Harpoon it is more likely that Singapore is using weapons compatible with its Atlas Elektronik Combat System. Judging by the weapons on the top of the TKMS line German Navy Type 212A, Singapore’s Type 218SG will use:
-  the Atlas Elektronik developed DM2A4 "SeaHake mod 4" 533mm heavyweight torpedo (HWT).
    This is noting Singapore is not listed as a US Mark 48 HWT operator.
-  With 8 torpedo tubes this provides room for deployment of at least 16 naval mines and/or 
-  8 or more medium sized UUVs (which can be weaponised, making them highly mobile very smart
    mines to defend Singapore or to block Chinese access to the Strait of Malacca and other
-  Germany (including TKMS) is developing the small short (20km) range missile known as
    the IDAS (Interactive Defence and Attack System for Submarines) used for surface to air, 
     anti-ship (eg. anti-pirate smuggler boats) and (light) land attack.

I see no evidence Singapore is using the US made Tomahawk longer range cruise missile, for submarines and other platforms (yet). There is a possibility the 218SG already has, or can be retrofitted with, a vertical multi-purpose lock (VMPL). This could vertically launch 6 Tomahawk cruise missiles (or similar), launch a large UUV, diver delivery vehicle or be used for special forces equipment storage.


-  Submarine Matters' February 19 and 20 2019.

-  Sebastien Roblin at The National Interest. March 2, 2019, with cited halfway down Sebastien's

-  Singapore's Straits Times, Feb 18-20, 2019.

-  Wikipedia to Feb 19, 2019 including

-  Janes Feb 19, 2019.

-  The Independent, Feb 19, 2019.

Singapore’s Ministry of Defence, February 18, 2019, including:



GhalibKabir said...

Hi Pete

It might as well be the Harpoon ranging between 130-200 km in range in the (140 km UGM-84D?) considering they are already deployed by their surface fleet frigates called the formidable class. even if not used till date, it is the most logical solution.

It is most likely a torpedo tube firing solution will be used for the Harpoon. Similar to the refitted type-209s in Indian service. I don't think a VLS makes much sense here. The Exocet is also a good choice offering 180 km range though I am not sure if it can be easily integrated with the Atlas. That or a MTCR range limited to 300 km Popeye SLCM could also be integrated if the US and Germany could find their 'geopolitical cojones' as the Germans make the Dolphins anyway.

Frankly in an area like the Malacca straits a missile like the IDSA might not be useful.

Anonymous said...


Re submarine weapons.

A vertical launch system is not required to operate long range missiles. Both Tomahawk & Scalp Naval missiles also come in torpedo tube fired versions. Though to be honest I don’t see the need in their case. They are more likely to leave that to others. Harpoon is currently used across their military, so it’s unlikely to change till a new whole of military conversion starts to become possible. Current Harpoon is starting to become obsolete even with the latest upgrades. If they do go for the F35, then that would tend to indicate JSM/NSM as the front runner. Konsberg has already indicated that changes to JSM to fit in F35A/C bomb bay has enabled the missile to now fit in mk41 VLS & standard torpedo tubes. So it would appear that a sub launch version is in the works. This would give it the whole of military scope, not only for Singapore, but many other countries including Australia. ie air launch, land launch, ship launch & submarine launch versions.


Unknown said...

Hi Pete,
The main task of new sub is to fight regular armed force .

"In the Five Power Defence Arrangements exercise, our submarine could not be detected by other ships, and in the bilateral exercise with India, we successfully fired a torpedo in the Andaman Sea," he said.


Supernova said...

Dear Pete,

Interesting postulation of the capabilities and missions of the Type 218SG. BTW the total land area of Singapore in 2018 is 724.2 sq km according to data.gov.sg

Pete said...

Hi Supernova

Thanks, you are right. I've changed the text to

"ongoing land reclamation projects have increased Singapore's land area from 582 km2 in the 1960s to 724.2 km2 in 2018."



Pete said...

Hi GhalibKabir

Thanks for your comments.

You'll note from my wording.

"There is a possibility the 218SG already has, or can be retrofitted with, a vertical multi-purpose lock (VMPL). This could vertically launch 6 Tomahawk cruise missiles (or similar), launch a large UUV, diver delivery vehicle or be used for special forces equipment storage."

I'm tentative: "possibility" "retrofitted" including "launch a large UUV, diver delivery vehicle or be used for special forces equipment storage".

I don't think Singapore would junk its Harpoon ownerships and go out and buy a French built Exocets.

There is also a possibility (if Taiwan, S Korea and Japan begin to build nuclear weapons) then Singapore may do likewise. In which case the Israeli "Popeye Turbo" connection in 650mm torpedo tubes or VMPL would be handy.

The 218SG has alot of torpedo tubes, with 8. Maybe 6 x 533m and 2 x 650mm?



Pete said...

Hi Anonymous [at 23/2/19 11:20 AM]

Your comments are all quite possible and see my response to GhalibKabir.

As well as the F-35A Singapore may also be looking at the F-35B https://www.defensenews.com/global/asia-pacific/2019/01/18/singapore-wants-the-f-35-to-replace-its-f-16s/

"Subsequent reports suggested it was keen on the short take-off and vertical landing F-35B variant. It is believed Singapore has a requirement of 40-60 aircraft, or enough to make up two or three squadrons."



Pete said...

Hi "Unknown"

Yes Singapore's subs can fight regular armed forces which does not preclude especially non-state based threats (eg. monitoring terrorist/pirates/smugglers on boats).

Because submarine heavy, expensive weapons are unsuited to blowing up boats a monitoring sub might then alert surface navy ships and helicopters to capture or destroy the terrorists/pirates/smugglers' boats.



Josh said...

@ Pete:

I suspect the main role of these boats is deterrence. Allowing even one of them to operate in those straights would cause massive disruption to trade for other much larger nations. While they might spend some time in other roles during peace time, their main goal would be to allow such a small country to punch above its weight in a conventional sea war.


Anonymous said...


My understanding is Singapore are interested solely on the F35B. My comment re the JSM/NSM in relation to F35 is version agnostic. It is the only anti-ship missile due to be integrated any time soon to the F35. On the B model, it is external only, on the A or C it can be internal or external. If Konsberg can get their scates on re a sub launched version (2026?), it would put them in the box seat for any F35 user that has Harpoon in the inventory. The current Harpoon missiles are fast approaching eol, especially for those like the UK that appear not to have gone with all the latest upgrades.

As an aside, in regards to the JSM, for once the Australian government has used its head. While they, along with Norway, have been funding some of the development, in offering to design & build a second (Australian) seeker that can integrate with the first (giving it a dual mode seeker - IR & RF), they have made Australia part of the supply chain. If, this also gets back ported to the NSM, even better.


Pete said...

Hi Josh

Yes deterrence would be the main role if Singapore were being threatened. As Singapore will have a wholey 218SG submarine force by the late 2020s these subs need to be multi-role (eg. just like Australia's and Germany's all of one submarine type). Different conditions/threats (peace, war or in between) would alter the priority list of roles.

I suspect Singapore would be selective as to who (China?) or what (Chinese warhips and maybe Chinese tankers?) Singapore would block.

Singapore might only be able totally block the Malacca Strait as part on a broad alliance action, given the international anger (even conventional missile strikes on Singapore) blocking would cause.



Pete said...

Sebastien Roblin, at The National Interest, has written an excellent article with some new facts and insights, titled “This Submarine Is "Invincible": Meet the Super Sub Headed to China's Doorstep” March 2, 2019

at https://nationalinterest.org/blog/buzz/submarine-invincible-meet-super-sub-headed-chinas-doorstep-45987

Incidentally 3/5ths down his article Sebastien cites my February 22, 2019 article above.


Pete said...

Supernova, at Full Frame, https://daisetsuzan.blogspot.com/

writes interesting articles about many types of weapons, including submarines, eg:

- "Invincible : Singapore's Type 218SG Submarine" 19 February 2019 at https://daisetsuzan.blogspot.com/2019/02/invincible-singapores-type-218sg.html


- Kure's [Oyashio and Soryu] Submarine Alley, 28 December 2018 at https://daisetsuzan.blogspot.com/2018/12/kures-submarine-alley.html


Anonymous said...

Singapore is one of key partner in China's Belt and Road Initiative and plays a very important role by engaging in mutually beneficial policies from covering economics, diplomatic, educational, technological to cultural exchanges.

What benefit would be for Singapore to act in ways that can be considered as attempt to contain China militarily ?

Rather, I see the constant upgrading of Singapore military as a benefit for bother the Republic and China's OBOR since since both share the same interest of keeping the region's SLOC open and free access for all, including Chinese commercial and maritime vessels.

Anonymous said...

I'm not so sure that the submarines will be used in police actions, one of the more well kept secrets that most don't notice is the 100+ ship coast guard. Compared to the navy, their coast guard is huge, one more submarine or 4 isn't even going to increase their capabilities even fractionally.

Pete said...

Hi Anonymous [19/3/19 6:03 AM]

Your point discerning Singaporean police vs coast guard forgets that Singapore has a "Police Coast Guard". This is noted in the text of my article and confimed by Singapore ie. in the following link:




Pete said...

Sebastien Roblin https://nationalinterest.org/profile/sebastien-roblin has written an excellent article on March 25, 2019 at The National Interest called

"This Submarine Is "Invincible": Check Out the Super Quiet Sub Headed Near China" at https://nationalinterest.org/blog/buzz/submarine-invincible-check-out-super-quiet-sub-headed-near-china-48962

In the the article (and incidentally :) Sebastien mentions "The Type 218’s potential uses and areas of operation are explored in greater detail in this article [1] by Peter Coates in Submarine Matters."

[1] https://gentleseas.blogspot.com/2019/02/what-singapores-type-218sg-submarines.html


Pete said...

Sebastien Roblin has written an excellent article at The National Interest of November 18, 2019 "Germany Has A New Submarine, But It Won't Be Patrolling Russian Waters" at https://nationalinterest.org/blog/buzz/germany-has-new-submarine-it-wont-be-patrolling-russian-waters-96661

This is on the politics, technical details and uses of Singapore's new Invincible class Type 218 submarines.