Singapore is an ally of the United States. After acquiring Germany's Newest Submarine, should China care more about that?

The wealthy but tiny nation of Singapore has invested in a strangely capable and expensive military for its size.

On February 18, 2018, officials gathered to celebrate the launch of a replacement state-of-the-art submarine at a shipyard in Kiel, Germany. But unlike similar Type 212 submarines previously built there, the seventy-meter long diesel-submarine isn’t destined to shadow Russian submarines within the cold waters of the Baltic.
Instead, the Invincible will lurk within the warmer Pacific waters around the Straits of Malacca within the service of the Republic of Singapore Navy. In so doing, the 2,000-ton submarine and her three forthcoming stablemates will become new factors within the ongoing multi-national competition for influence over the South China Sea.

Singapore is an island city-state sitting astride the Straits of Malacca, which offers the foremost direct route for commercial traffic between East Asia and therefore the Indian Ocean—totaling one-fourth of all the world’s traded goods, including 1 / 4 of all oil.

The wealthy but tiny nation has invested in a strangely capable and expensive military for its size—in 2017 it had the fifth-highest defense spending per-capita on the earth. it's purchased major Western weapon systems including 100 F-16 and F-15SG fourth-generation jet fighters, Leopard 2 tanks and last, four to 12 F-35stealth fighters.
Singapore is adjacent to 2 more populous countries (Malaysia and Indonesia) and also holds China as a crucial commercial partner. However, it's insisted China's claims to sovereignty over large swathes of the South China Sea should be adjudicated by legal means and hosts U.S. Navy P-8 maritime patrol planes and Littoral Combat Ships.

Thus, while Singapore considers itself a neutral actor, it's sometimes perceived as tilting more towards Washington to counterbalance China’s growing military power. Not incidentally, Beijing has explored bypassing Singapore through the development of the Kra canal through Thailand.
The Invincible, also designated the sort 218SG, joins the growing numbers of air-independent propulsion (AIP) submarines active within the Pacific within the navies of China, Japan, Singapore, and South Korea. AIP allows a relatively cheap diesel-electric submarine to cruise underwater at slow speeds for weeks at a time, rather than having to surface or snorkel every few days.

Type 218, like contemporary German designs just like the Type 212 and 214, uses hydrogen fuel-cells for this purpose, a more advanced and less noisy configuration than the Stirling heat-cycled AIP engine used in Singapore's two Swedish-built Archer-class submarines which entered service in 2011 and 2013. The Invincible is claimed to possess 50 percent greater endurance than the Archers, implying it can remain submerged four to 6 weeks before wanting to surface. Fuel-cell AIP does have the disadvantage of being costlier and is potentially volatile should the submarine sustain damage, however.

AIP submarines still can’t sustain speeds of 30 knots and remain underwater indefinitely the way a nautilus can. Type 218 reportedly has the highest underwater speed of 15 knots or 10 knots surfaced. But AIP-submarines cost one-fourth or less the worth of a nuclear sub, and their limitations aren't nearly as important when working on shorter-range patrols.

Type 218SG

Germany has already exported chubby Type 214 export submarines to South Korea in Asia. However, Singapore sought a rather larger, more advanced design to exchange its old Challenger-class submarines, which Singapore first purchased from Sweden within the 1990s.

Type 218 boasts a classy new combat system jointly developed by Germany and Singapore featuring computer-assisted decision-making algorithms. The resulting high degree of automation allows a crew of only twenty-eight to work the sub, rotating on eight-hour shifts rather than more fatiguing twelve-hours. this might leave more room for intelligence-gathering specialists or special operations troops.

The Type 218SG also can carry a heavier weapons load, with eight tubes for launching 533-millimeter heavyweight torpedoes rather than the more typical six. While official details of onboard armament remain unavailable, additionally to heavyweight torpedoes, the sort 218 tubes could conceivably be outfitted with naval mines or anti-ship or land-attack missiles just like the Harpoon and Tomahawk or the German fiber-optically guided IDAS missile, which may hit both surface targets and slower-moving aircraft like sub-hunting helicopters.

In a statement to media, Singaporean defense Minister Ng Eng Hen emphasized the submarine’s usefulness for various peacetime operations, including curbing piracy, arms smuggling, and human trafficking. However, the sort 218s also give the island state an intimidating conventional deterrence capability: if Singapore feels threatened or compelled to hitch a world alliance during a crisis, its submarines could effectively deny access to the ultra-valuable strait. Even a numerically superior adversary would struggle to seek out long-endurance submarines which will remain submerged for over a month at a time.

The Invincible’s X-shaped rudder also affords it greater maneuverability—useful for navigating the shallow, rocky Strait, which is merely 1.5-miles wide at its narrowest point. The strait has many small inlets and islands, around which a submarine could settle onto the seafloor and wait in an ambush while remaining extremely difficult to detect.

The Invincible’s improved ocean-going capabilities mean it could also contribute to longer-range patrols of sea lines of communication within the Indian Ocean, or to Taiwan, with which it's a defense partnership.

More routinely, the sort 218’s advanced sensors and facilities will give Singapore significant intelligence-gathering capabilities, particularly for intercepting signals, deploying operatives, tracking the movements of Chinese diesel-electric submarines around the strait and building a “threat library” on their acoustic signatures. Such intelligence could also be exchanged with us and regional partners, with which Singapore has shared intelligence within the past.

The Type 218’s potential uses and areas of operation are explored in greater detail during this article by Peter Coates in Submarine Matters.

For now, the Invincible is about to start sea trials while a crew commanded by Lt. Col. Jonathan Lim is training in Germany, preparing for commissioning in 2021. Meanwhile, her sister ships Impeccable, Illustrious and Indomitable are set to be launched in 2022, 2024 and beyond, respectively, with the latter eventually replacing Singapore’s Archer-class submarines.