"China Maritime Report No. 31: China's Submarine Industrial Base: State" by Sarah Kirchberger

"China Maritime Report No. 31: China's Submarine Industrial Base: State" by Sarah Kirchberger

Publication Date ~ September, 2023

Publisher - China Maritime Studies Institute, U.S Naval War College

City

Newport, Rhode Island

Keywords

China, China Maritime Studies Institute, CMSI, People’s Liberation Army, PLAN, nuclear, submarines, nuclear submarines, ssn, undersea warfare, ssbn, industry

Recommended Citation

Kirchberger, Sarah, "China Maritime Report No. 31: China's Submarine Industrial Base: State-Led Innovation with Chinese Characteristics" (2023). CMSI China Maritime Reports. 31.
https://digital-commons.usnwc.edu/cmsi-maritime-reports/31

In recent years, China’s naval industries have made tremendous progress supporting the modernization of the People’s Liberation Army Navy (PLAN) submarine force, both through robust commitment to research and development (R&D) and the upgrading of production infrastructure at the country’s three submarine shipyards: Bohai Shipyard, Huludao; Wuchang Shipyard, Wuhan; and Jiangnan Shipyard, Shanghai. 

Nevertheless, China’s submarine industrial base continues to suffer from surprising weaknesses in propulsion (from marine diesels to fuel cells) and submarine quieting. Closer ties with Russia could provide opportunities for China to overcome these enduring technological limitations by exploiting political and economic levers to gain access to Russia’s remaining undersea technology secrets. 

Key Points

here are some key points about China's submarine industrial base:

• China has three main shipyards that build submarines - Bohai in Huludao, Wuchang in Wuhan, and Jiangnan in Shanghai. All have undergone major expansions and upgrades in recent years.
• China's submarine fleet has rapidly grown and made major advances, but some key technology weaknesses remain in areas like propulsion and quieting. There are still issues with the quality and reliability of Chinese marine diesel engines and with the acoustic signatures of nuclear submarines.
• To address these issues, China is pouring resources into R&D on next-generation technologies like lithium-ion batteries, pump-jet propulsion, advanced materials, and noise reduction. There is also extensive research on emerging technologies like AI and autonomous systems.
• Collaboration with Russia could help China access submarine technology in areas where it still lags behind, like quieting and nuclear propulsion. There are signs of growing cooperation in sensitive areas like acoustics, Arctic operations, and nuclear fuel.
• China aims to leverage civilian R&D and commercial shipbuilding expertise for military gains. This "military-civil fusion" strategy involves joint ventures, technology transfer, and integrating commercial and military production.
• Submarine production is a strategic priority with strong state backing. Funding pours in from state banks, listed subsidiaries, and even accessing foreign capital markets. This enables largescale R&D funding and facilities expansion.

In summary, China's submarine industrial base has made rapid gains but retains some weaknesses. Ongoing R&D, technology transfer and expanded production aim to erase remaining gaps.

Shipyards

here are some details on the capacities of China's three main submarine shipyards:

Bohai Shipyard (Huludao):

• Total area of 3.6 km2
• China's largest covered berths, including two 300,000 DWT dry docks
• Annual shipbuilding capacity up to 4,000,000 DWT
• Constructs all nuclear-powered submarines

Wuchang Shipyard (Wuhan):

• New shipyard site 10x larger than old one, about 1.5 miles along riverbank
• Covered halls added for Yuan-class submarine construction
• Evidence of mass production with several boats under construction simultaneously
• Main shipyard for conventional submarines

Jiangnan Shipyard (Shanghai):

• New Changxing shipyard about 64% larger than old site, around 11.5 km2
• Naval shipyard area around 1.4 km2
• Involved in construction of half of Yuan-class submarines
• Also builds prototypes and tests new designs
• Massive capacity for large surface ships demonstrated

In summary, all three yards have undergone major expansions and appear to have greater submarine construction capacity than most other countries' yards. Wuchang and Jiangnan build conventional subs, while the nuclear-powered subs are concentrated at Bohai.

Diesel Engine Quality Issues

The report highlights some lingering issues with the quality and reliability of Chinese marine diesel engines for submarines:

• China still relies on imported or license-produced German MTU diesel engines to power its current Song- and Yuan-class conventional submarines.
• For the submarine export project to Thailand, China offered its indigenous CHD620 engine when Germany blocked MTU exports. But Thailand sees the Chinese engine as "unproven" and potentially risky.
• This implies the CHD620 has never been integrated into an operational submarine before. Using an untested engine design creates uncertainty about its performance and safety.
• Specifically, there could be issues ensuring proper and safe operation of the exhaust system when discharging exhaust gases underwater at snorkeling depth. Engine malfunctions here would endanger the crew.
• More broadly, it seems surprising that China has not fully mastered diesel engine technology for subs given its expertise in other marine and naval systems.
• The report speculates China may have focused R&D on more advanced propulsion types like AIP and nuclear power rather than perfecting conventional diesel tech.

In summary, the continued reliance on German submarine diesels and Thailand's concerns about accepting an untested Chinese alternative engine point to lingering quality and reliability issues with indigenous Chinese marine diesel engine technology for subs. Mastering this basic propulsion system remains an enduring weakness.

 Nuclear Power Quieting Issues

The report highlights several issues with the acoustic signatures of China's current nuclear submarines:

• Chinese SSNs like the Type 093 Shang-class have reportedly been tracked by adversaries like Japan, implying they are still too noisy and easy to detect.
• Sources state the Shang-class lacks advanced features like a pump-jet propulsor and still struggles with noise from internal equipment and vibration.
• The Type 094 Jin-class SSBN also has a flawed "turtle-shaped" hull design that creates a noticeable acoustic signature at higher speeds.
• China lacks experience with specialized sound-dampening coatings on par with top Russian and Western submarine builders.
• In general, Chinese nuclear subs are rated as noisier than modern Russian and American counterparts. Estimates put the Shang SSN at 80-100db versus 95-105db for a U.S. Virginia-class.
• This is attributed to China still lacking mastery of technologies like noise-isolating rafts, advanced propulsors, anechoic coatings, and precision hull welding.
• Next-generation Type 095 SSN and Type 096 SSBN aim to rectify this through expected improvements like pump-jets, single-hull design, and new integrated floating rafts.

In summary, acoustic stealth remains a key weakness for Chinese nuclear submarines compared to Western and Russian peers. The extent of progress with next-generation boats will demonstrate if these noise issues persist.

Funding New Technology

The report does not specifically address how recent problems in the Chinese economy might impact funding for submarine technology. However, some relevant points can be made:

• Naval shipbuilding and submarine production have been strategic priorities with strong state backing under Xi Jinping. This includes preferential access to credit from state banks.
• The report notes that defense spending continues to rise even as China's economy slows. The latest budget showed military outlays outpacing overall GDP growth.
• Submarine construction is very costly, both for initial acquisition and lifetime maintenance/operation. But this high price tag has not deterred major outlays so far.
• China aims to fund R&D via commercial spin-offs and market mechanisms under its "military-civil fusion" strategy. A weakened economy could hamper this.
• However, China possesses enormous financial reserves and capacities to redirect spending toward military priorities as needed.
• The West underestimated Soviet military spending even when its economy was collapsing. China may take similar steps to sustain strategic programs.
• Ultimately, an economic downturn may force China to choose between competing defense priorities. But nuclear subs and undersea power projection likely remain vital interests.

In conclusion, China has shown both the willingness and capacity to continue heavily funding submarine tech even amidst economic woes. While an economic crisis could force tough choices, undersea warfare capabilities will likely remain a top funding priority given their strategic value.