In 2016, President Tsai Ing-wen (蔡英文) announced that Taiwan would build its own indigenous diesel-electric attack submarines (SSK) after failed efforts to find a country that would sell it SSKs.
On Sept. 28, Tsai launched the first of a new class of Republic of China (ROC) Navy SSKs, designated the Hai Kun class (SS-711). Eight of the indigenous defense submarines (IDS) are planned. The first vessel is to undergo equipment installations and tests before becoming fully operational as early as 2025.
Although Taiwan wanted to produce all aspects of the new submarine, at least seven countries provided assistance to ensure it had the capabilities desired by the ROC Navy: the US provided Lockheed-Martin’s AEGIS combat system, 46 Raytheon MK-48 MOD 6 Advanced Technology (AT) heavyweight torpedoes and Raytheon’s UGM-84L sub-launched Harpoon Block II missiles; South Korea, India and the UK provided parts, technology and expert advice; with France and Japan also helping.
Taiwan acquired 107 unspecified technologies from foreign companies to complete the IDS program.
The ROC Navy might have modeled the IDS on Japan’s Soryu-class SSKs, with an X-shaped stern, combining diving planes and rudders.
Former US president Donald Trump’s lifting of restrictions on selling submarine technology in 2017 with the sale of MK-48 torpedoes, followed by submarine combat management systems and other technical assistance, was critical to the development of the IDS program.
IDS capabilities would assist Taiwan’s military to defend its national territory and to monitor the Chinese People’s Liberation Army (PLA) Navy, the Chinese Coast Guard, China’s maritime militia and other unfriendly ships near Taiwan.
Taiwan’s SSKs can inflict punishment on the PLA and its navy to help deter the Chinese Communist Party (CCP) from ordering an attack.
Attack submarines such as the Hai Kun-class vessels are used for seek-and-destroy missions on enemy ships and submarines, surveillance and reconnaissance, irregular warfare, covert troop insertion, as well as mine and anti-mine operations and defending friendly ships.
Reports last month said that Taiwan is also building a midget submarine, possibly uncrewed.
Up Media and H.I. Sutton reported that the Huilong design could be a testbed for the IDS program and a test model for an uncrewed underwater vehicle that could be used as a mini-IDS or alongside the IDS vessels.
The Huilong weighs about 100 tonnes compared with the 2,500 to 3,000-tonne IDS vessels, and is 30m long and 3.6m wide compared with the IDS vessels, which are 70m long and 8m wide. The ROC Navy should launch the Huilong before the end of this year.
With up to eight new ROC Navy submarines to be launched, it could wreak havoc on hostile forces around Taiwan, including its outlying islands.
According to PLA doctrine and the most recent ROC National Defense Report, the PLA has been conducting exercises in preparation for conflict and to conduct “gray zone” intimidation. What could the IDS vessels do for Taiwan?
The ROC Navy could use its submarines to collect intelligence during PLA exercises to help plan and design countermeasures for a potential conflict.
In a hypothetical PLA joint firepower strike operation, the submarines could target PLA Navy ships and submarines that could launch missiles at Taiwan.
They could help protect Taiwan’s territorial waters by patrolling and sinking PLA Navy vessels that enter.
During a blockade of airspace and seas, the same kinds of factors apply. The submarines could conduct reconnaissance, and interdict ships and submarines conducting or supporting a blockade.
During an invasion and even if the PLA gained a foothold in Taiwan proper, the submarines could continue to interdict ships supporting PLA operations by restricting supplies.
They would be deadly for PLA aircraft carrier strike groups attacking Taiwan.
The IDS program is an asymmetric weapon that can counter PLA aggression.
If a conflict were to expands beyond Taiwan and China, the submarines could work with other submarine-capable navies, such as those of Japan, the US and South Korea, to restrict PLA Navy operations within and beyond the first island chain.
Taiwan could contribute by monitoring the Miyako Strait with Japanese submarines and the Bashi Channel between Taiwan and the Philippines.
Philippine President Ferdinand Marcos Jr recently announced that Manila intends to acquire submarines, possibly the French Scorpene class. Japan has 20 SSKs and South Korea has 19.
China has 56 submarines — 44 SSKs, six nuclear-powered general-purpose attack subs (SSN) and six ballistic missile-carrying submarines (SSBN).
The US has 68 — 50 SSNs, 14 SSBNs and four guided-missile submarines.
Taiwan’s east coast is ideal for hiding submarines, as sea depth increases rapidly close to the coast. Taiwan should consider building submarine support bases for allies and for its own growing fleet. The presence of allied submarines would also deter CCP aggression.
Taiwan’s new submarines would substantially enhance the nation’s defense and augment an allied military effort to stop CCP aggression. Should deterrence fail, Taiwan’s submarines would inflict severe damage on potential PLA hostile action.
Any PLA ship or submarine is at risk of sinking from this stealthy indigenously produced underwater weapon system.
Guermantes Lailari is a retired US Air Force Foreign Area officer specializing in counterterrorism, irregular warfare and missile defense. He holds advanced degrees in international relations and strategic intelligence. He was a Ministry of Foreign Affairs Taiwan Fellow in Taipei last year and is a visiting researcher at National Chengchi University.
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