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5.4   Modernization of the PLA Navy II - Submarines

1 April 2018

Introduction to Submarines

Submarines can be broadly categorized into non-nuclear-powered (aka conventional) and nuclear-powered.

Non-nuclear-powered submarines, also referred to as SSK (Sub Surface Hunter-Killer) by US Naval designation, can dive to a depth of 150-300 m and have an underwater speed of 15-20 knots. They are typically powered by a diesel engine when running on the surface and by electric batteries when submerged. They have a large network of batteries which are charged by the diesel generator when they snorkel (i.e. travelling just below the surface of the water with the periscope and the diesel generator exhaust pipe above the water surface). Once their batteries are charged, the diesel-electric subs dive into the ocean and run silently on battery power with the diesel generators shut down. While underwater, the batteries on board power the propeller and other electrical systems on board the submarine. Because of their power source, diesel-electric submarines are or popularly called as diesels.

Common Acronyms

SS/SSK:   non-nuclear-powered attack submarines (SS for submersible ships); aka Diesel-electric attack submarines or simply diesels

SSN:         nuclear-powered attack submarines, aka unofficially as “fast attacks” in US.

SSBN:      nuclear-powered ballistic missile submarine aka strategic missile submarines (i.e. those carrying nuclear warheads)

SSGN:      nuclear-powered guided missile submarine

AIP         air-independent propulsion system. Found in newer SSs. Low acoustic signature making them harder to detect.

SLBM:      submarine-launched ballistic missiles

SLCM:      submarine-launched cruise missiles

ASCM:     anti-ship cruise missile

ASBM:     anti-ship ballistic missile

LACM:     land-attack cruise missiles

The advantage of a diesel-electric submarine is that it is relatively easy to procure, train crew and operate so even small navies can acquire and operate them. Also, because it is powered by electricity when running submerged, it can be extremely quiet and hard to detect. Russia's KILO-class submarines, for example, have earned the nickname "Black Hole" for their ability to evade detection.


The disadvantage, however, is that once the battery gets drained, these submarines have to surface again to recharge their batteries. Typically, they can remain submerged for only a few days (4 -5 days) when running at slow speed, and a few hours at top speed. This exposes them to detection by enemy radars and makes them an easy target for hostile anti-submarine assets. A submarine that needs to surface every day loses its element of surprise and increases its vulnerability to hostile anti-submarine assets.


This shortcoming, however, has been addressed in recent years with the emergence of air-independent propulsion (AIP) system which encompasses a variety of technologies that allow generators onboard a submarine to operate while consuming little or no oxygen. It is usually implemented as an auxiliary source, with the traditional diesel engine handling surface propulsion. Basically, an AIP system works by generating electricity which in turn drives an electric motor for propulsion or recharges the sub’s batteries when the sub is submerged. This allows the sub to retain its extremely low noise signature without compromising its performance. When compared to nuclear-powered subs, modern non-nuclear subs running on AIP can be virtually silent and are potentially stealthier. This is because nuclear subs’ reactor must constantly pump coolant thus generating some amount of detectable noise. Moreover, unlike nuclear reactors of nuclear boats which have to run 24×7, the engines on diesel-electric subs can be shut down or switched on whenever needed. They can just stay dead in the water to avoid detection.[1] The bottomline is that AIP technology allows conventional subs to continue sailing underwater longer and retain the element of surprise by remaining undetected. In April 2006, a German Navy sub U-32, equipped with a Siemens hydrogen fuel cell AIP, made a 2800 km uninterrupted underwater journey without surfacing/snorkelling. This is in stark contrast to non-AIP equipped subs which can cover only 500-800 km before they have to surface and recharge their batteries by running noisy diesel generators. In 2013, U-32 again set a record by traveling underwater continuously for 18 days without surfacing compared to a non-AIP diesel sub which has an underwater endurance of just 4-6 days.[2] Finally, another good thing about AIP technology is that it can be easily installed on existing older generation submarines by simply inserting a new hull section during a retrofit.


Besides the issue of power source, conventional submarines’ low top speed of 15-20 knots makes them impossible to outrun torpedoes or ASW ships. Their limited diving depth of 150-300m also makes them vulnerable in deep water regions where they cannot use depth for concealment. Finally, their small size not only limits their weapon arsenal to only 12-20 torpedoes/missiles (exceptions like the Japanese Soryu exist) but also makes long deployments very unpleasant for the crews.


While nuclear-powered designs still dominate in submergence times and deep-ocean performance, high-tech non-nuclear attack subs are small and agile which makes them deadly in shallow water regions. They are therefore highly effective in coastal operations and pose a significant threat to less-stealthy and less-manoeuvrable nuclear submarines.


One scenario, for example, is to use the advantage offered by increased underwater endurance for ‘ambushing’ an approaching fleet. In such a scenario, an AIP equipped submarine can roam near a strait, waiting for its target to approach. The sub will be running at ultra-quiet speeds of 2-4 knots for several weeks and then attack the target when it appears, using its torpedoes. Even though a non-AIP equipped sub can do the same thing, its waiting period, which is very essential for an underwater ambush, is significantly lesser. In another scenario, an AIP-equipped sub can roam near enemy territory for far longer compared to a non-AIP sub to gather intelligence. AIP gives these quiet diesel subs an advantage by allowing them to loiter for weeks without the need to surface.


Looking ahead, with the increasing capacity and reliability of batteries as well as improvements in capabilities of AIP technology as a result of extensive research in both areas, AIP-equipped submarines of the future may be able to stay underwater for months at a time, making them pseudo-nuclear submarines. Hence, more modern navies can be expected to adopt AIP technology for their diesel-electric submarine fleets.


Nuclear-powered submarines are powered by a nuclear reactor which is modified for use in a confined, underwater environment. These nuclear reactors produce heat, which in turn produces steam, which works on the steam turbines and turns a shaft. This shaft is connected to the propeller as well as a generator which recharges the battery for on board use. This nuclear reactor gives them an unlimited range, and the ability to stay under water for months without surfacing even when running at high speed.[3] Current generations of nuclear submarines, for example, never need to be refuelled throughout their 25-year lifespans. Their operational range is thus limited only by consumables such as food.[4]  On-board oxygen generating systems and a large supply of food and water gives them a realistic 90 days of continuous underwater time before they need to be re-supplied. Finally, in addition to their unlimited range and long submerged time, nuclear subs are a nightmare for anti-submarine warfare (ASW) assets, because they can dive to depths of over 600 m and travel at a speed of 30-35 knots submerged making them difficult to be targeted. This gives them a huge advantage over diesels.


One disadvantage of nuclear-powered submarines is that nuclear reactors are inherently noisier than electric motors running on battery power. This is because nuclear subs’ reactor must constantly pump coolant thus generating some amount of detectable noise. Hence, nuclear subs make a certain amount of noise by default when they are running so advanced sound suppression techniques have to be used to reduce their acoustic signature. Moreover, reactors are always online and they cannot be turned off to allow nuclear subs remain stop dead in the water. Last, the high cost of nuclear technology means that’s why only 6 countries in the world operate nuclear subs and almost 50 countries operate diesel subs.


Nuclear-power submarines can be broadly divided into attack submarines (SSNs) and strategic missile submarines (SSBNs).


Attack submarines (SSN, aka hunter-killer submarine) are those specifically designed for the purpose of attacking and sinking other submarines, surface combatants and merchant vessels to protect surface fleets and the strategic missile submarines. They are the unseen king of the oceans. Some attack subs are also armed with cruise missiles mounted in vertical launch tubes, increasing the scope of their potential missions to include land targets. The presence of these subs is so powerful that during the Falklands war the Argentines withdrew their entire navy from combat after their ship General Belgrano was sunk by a British SSN. Attack submarines generally do not carry ballistic missiles which are usually armed with nuclear warheads. In 2011, the US Defense Department tabled a proposal to develop a new conventional ballistic missile for fielding on attack submarines. However, the U.S. Congress, Russian leaders and many nuclear strategy experts warned that fielding conventional ballistic missiles on nuclear-capable submarines could be a potentially destabilizing way to carry out the strike mission.  According to this view, Moscow or Beijing might mistake a ballistic missile launch from a submarine for a nuclear salvo, and set loose a devastating response.[5]


Strategic missile submarines (SSBN, aka ballistic missile submarine), in contrast, carry submarine-launched ballistic missiles (SLBMs) with nuclear warheads enough to destroy a continent. Because their mission is to stay hidden and fire nuclear tipped ballistic missiles in case of a nuclear war, they are the mythical underwater monsters which always stay at a great depth and almost never seen. If an SSBN ever has to fire its missiles in actual combat, it would mean World War 3. They became a major weapon system in the Cold War because of their nuclear deterrence capability. Together, the SSBNs, the land-based intercontinental ballistic missiles (ICBMs) and the airborne strategic bombers form the triad nuclear weapons delivery system. SSBNs’ acoustic quieting feature makes them difficult to detect, thus increasing their probably of surviving a first strike. They can then carry out a counterstrike with their nuclear warheads thousands of kilometres from their targets. Strategic missile submarines are therefore a key element of the mutual assured destruction policy of nuclear deterrence.


Strategic missile submarines are extremely large subs when compared to attack subs. The smallest SSBN is almost the size of the largest SSN. Russia built the Typhoon class, which is the largest submarine in the world and will remain so for decades to come. To detect these submarines and destroy them is a Herculean task. They carry powerful sonar and will probably detect you before you detect them. Their great diving depths and superior speed make hunting them extremely difficult.


Because of the serious threat submarines can pose to aircraft carriers, China has placed high priority on undersea warfare. Along with improvements to its surface fleet, the PLAN is also replacing an oversized fleet of old, loud, and vulnerable coastal-defence submarines with a modern undersea warfare force that, though smaller, is more survivable and capable of exploiting China’s improvements in targeting US surface-strike forces at increasing distances.


Even though Chinese submarines can be expected to become a key element in China’s strategic nuclear deterrence force (more about that later), however, its main mission now is still anti-carrier warfare using anti-surface missiles. Because of their stealth and the increasingly more powerful arsenal they carry, it has been said that China’s submarines are “the most troublesome problem today” for the US surface fleet in the Western Pacific.[6]


Since the mid-1990s, China has acquired 12 Russian-made KILO-class non-nuclear-powered attack submarines (SSs) and put into service at least five new classes of indigenously built submarines, including the following:.

  • SSBN  :  JIN class (Type 094) For nuclear deterrence

  • SSN    SHANG class (Type 093/093A)

  • SS       SONG class (Type 039/039G)  

  • SS       YUAN class (Type 039A/B/C or Type 41) &

  • SS       QING class (Type 32)

China's Nuclear-Powered Strategic & Attack Submarines (JIN & XIA, SHANG & HAN Classes)

PLAN has two classes of nuclear-powered submarines: JIN-class (Type 094) SSBN and the SHANG-class (Type 093) SSN.


JIN-class (Type 094) SSBNs, with a range of 7,500 km, are PLAN’s strategic missile submarines outfitted with second generation intercontinental-range Julang-2 (JL-2) SLBMs. There are four in operation, the minimum necessary for conducting continuous deterrent patrols and they are based at Longpo Naval Base on Hainan Island with the South China Sea Fleet.[7] First entered into service in 2014, the JIN-class SSBNs constitute China’s first credible, sea-based nuclear deterrent. They replaced the XIA-class (Type 092) SSBNs which were commission in 1987 but never completed a successful nuclear deterrent patrol. The Type 092 SSBN was reportedly so noisy during initial sea trials that its crews couldn't sleep. Meanwhile, there are also reports about a more modern and advanced Type 096 SSBN and armed with a new more lethal missile, the JL-3. Speculated to be named TANG-class, construction is expected to begin in the early 2020s.[8] Deployed appropriately, any of the more modern submarines can strike the United States with nuclear missiles. The Type 096, with a range of 10,000km, can strike the U.S. from secure areas near China’s coast.  The Pentagon currently believes that China will build around eight SSBNs in total, giving the PLAN the capacity to maintain multiple boats on continuous patrol.  Much depends, however, on whether China shifts its overall nuclear posture from minimal deterrence to active pursuit of secure second strike capability.[9]


SHANG-class (Type 093) SSNs, on the other hand, are PLAN’s latest nuclear-powered attack submarines. Their initial production run stopped after only two hulls were launched in 2002 and 2003 presumably because of their noisy reactors and propulsion systems, especially when run at high speeds. These defects make them highly detectable to enemy anti-submarine effort, thus limiting their combat potential. In 2012, production resumed with four additional hulls of an improved variant, the Type 093B SSN, which possibly features a vertical launch system (VLS) and carries the YJ-18 advanced anti-ship cruise missile (ASCM) with a range of 400 km. They are also quieter because of advances in Chinese metallurgy and reactor design. These six SHANG-class submarines will replace the aging HAN-class (Type 091) SSN on nearly a one-for-one basis in the next several years. Over the next decade, PLAN will produce a new SHANG-class variant, the Type 095 SSGN, which would not only provide a generational improvement in many areas such as quieting and weapon capacity but also improve the PLAN’s anti-surface warfare capability as well as providing PLAN with a more clandestine land-attack option. The 093B is thus said to be a transition platform between the 093 and the forthcoming 095.[10] In 2015 the Asian Military Review journal reported the PLAN would build up to 14 Type 095s.[11] 

China's Non-Nuclear-Powered Attack and Auxiliary Submarines (KILO, MING, SONG, YUAN, QING)

Like Russia, China also possesses a robust conventional/non-nuclear/diesel-electric attack submarine fleet. PLAN started with its own ROMEO-class (Type 033) submarines by reverse engineering the Russian ROMEO-class in the 1960s.[12] In 1974, two MING-class (Type 035) SSs based on a heavily improved redesign of the older Type 033 were built. During the 1980s and 1990s, further improvements in terms of noise reduction, weapons, sensors and crew living standards resulted in the Type 035A and 035G variants. By the early 2000s, PLAN came up with the MING-class (Type 035B), which features a redesigned conning tower and portions of the hull as well as the capability to launch land-attack cruise missiles (LACMs) from their torpedo tubes. A total of four Type 35B boats were commissioned between 2000 and 2003.


The MING-class is succeeded by the SONG-class (Type 039) which is the first indigenously built submarine of China. The first SONG-class was launched in 1994 but was not commissioned until June 1999 due to design and performance problems. In part as a hedge against the higher risk SONG-class project, PLAN commissioned more than 20 MINGs from 1980s to 2000s.[13] In 1999, following extensive redesign work, a new modified version known as Type 039G was launched. The new design reduced the acoustic signature and enhanced the underwater performance of the submarine. Two more were soon commissioned in 2001 and 2003.[14] Between 1999 and 2006, a total of 13 SONG-class SSs were built.[15] In 2006, reports of a submerged SONG-class attack submarine shadowing Japan-based CV-63 Kitty Hawk in the East China Sea near Okinawa without being detected caused great embarrassment to the Americans. The boat was only spotted by one of the carrier's planes on a routine surveillance flight when it surfaced within five miles of the carrier, inside the carrier’s screen of escorts.[16] The incident demonstrates not only possible limitations of US anti-submarine warfare (ASW) capabilities but also the growing competence of Chinese submariners.


In 2006, the SONG-class (Type 39) is succeeded by YUAN-class (Type 039A/B/C, aka Type 041 by some). The Yuan-class is purportedly one of the quietest submarine classes in the inventory of the PLAN. It is the PLAN's first class of diesel-electric submarines to be equipped with the Swedish developed heat-converting Stirling engine that can use an AIP to efficiently propel the ship electrically for weeks, albeit only at slower speeds. PLAN has so far commissioned fifteen YUAN-class Type 039A (aka Type 041) diesel submarines using Stirling AIP technology, with another twenty planned.[17] Today, the YUAN-class conventional submarine is one of the sharpest spears in China’s maritime arsenal. Its small size and stealth (augmented by AIP) suggest that it is a good fit for the shallow waters of China’s “near seas.[18]


In 2012, PLAN also commissioned the new QING-class (Type 032) conventional submarine.  According to IHS Jane’s Fighting Ships 2017-2018, it is about one-third larger than the YUAN-class design. Observers believe the boat may be a one-of-kind test platform.[19] What is unique is that, unlike the other diesel-electric submarines, the Type 032 can fire not only long-range cruise missiles, but also submarine-launched ballistic missiles (SLBMs) with the capacity to send a nuclear warhead across the ocean. Situated on the vessel’s elongated sail are two or three Vertical Launch Systems (VLS) tubes used to fire JL-2A (JuLang) ballistic missiles. The JL-2A is believed to have a range approaching 5000 miles and can carry a single one-megaton nuclear warhead, or three or four ninety-kiloton independent re-entry vehicles (MIRVs). The JL-2 was first tested in 2001 and constitutes the main armament of China’s JIN-class (Type 094) nuclear-powered submarines which embarked on China’s first nuclear deterrence patrol in 2015. Hypothetically, the non-nuclear-powered QING-class (Type 032) could be a cheaper, shorter-endurance nuclear deterrence compliment to the Jin-class SSBNs.[20]


Besides the indigenously designed and produced SONG-class and Yuan-class conventional submarines, PLAN also acquired two KILO-class SSs in 1995 and has continued to purchase Kilo-submarines from Russia as recently as the early 2000s.


In short, despite increasingly efforts to develop nuclear-powered submarines with longer working range, PLAN is still building a powerful conventional submarine fleet as the backbone of its underwater fighting force. Meanwhile, the workhorses of China’s modern conventional submarine force are the locally built SONG- and YUAN-class boats powered by state-of-the-art diesel engines designed by MTU Friedrichshafen GmbH of Friedrichshafen Germany and the 12 advanced KILO-class submarines imported from Russia. Even the aged MING-class (Type 035) submarines can still be useful as minelayers or as bait or decoy submarines that can be used to draw out enemy submarines (such as U.S. SSNs) that can then be attacked by other Chinese naval forces. As the mission of the PLAN expands and gravitates toward blue water, however, nuclear powered SSNs and SSBNs with better endurance and range will likely grow in importance.

MING (035A/B)

SONG (039/039G)

YUAN (039A/B/C or 041)

QING (032)*

HAN (091)

SHANG (093/093B)

SHANG (095)*

XIA (092)

JIN (094)

TANG (096)*

* Under development

China's Submarine Force Composition

China's Submarine-based Nuclear Deterrence Capability


China initiated its submarine-launched ballistic missiles (SLBM) research in 1958 with JULANG-1 (JL-1 巨浪-1), with assistance from the Soviet Union. However, development of China’s SLBM program was intermittent during China’s Mao-era political leadership (1949–1976) because of budgetary constraints, political events, and restricted access to oceans. It was only after the leadership ascension of Deng Xiaoping in 1978 that China’s SLBM program received new emphasis. In 1982, China conducted the first successful test-launch of a JL-1 missile from a XIA-class (Type 092) SSBN, China’s first generation of operational SSBNs.


China’s current SSBN program, the JIN-class (Type 094), was initiated in the 1980s but first entered into service in 2014. Each JIN-class SSBN carries twelve JULANG-2 (JL-2 巨浪-2) SLBM which was deployed in 2015. JL-2 is a naval variant of the land-based DONGFENG-31 (DF-31东风-31). Each JL-2 is capable of carrying either 3 – 8 Multiple Independently Targetable Re-entry Vehicles (each yielding 90kT) or a single warhead (yielding 250-1000 kT) over a range of 8,000 – 9,000 km. [21]

Together, the four JIN-class SSBNs are supposed to give the PLAN its first credible long-range sea-based nuclear capability. Recent satellite imagery shows all four JIN SSBNs simultaneously in port, suggesting that China does not currently have a policy of continuous-at-sea-deterrence.


China’s current nuclear deterrence strategy is best characterized as a nuclear counterstrike strategy (核反击), which some scholars have summarized as “assured retaliation.” Although China has long worked to develop a more credible second strike capability, such as through improved road-mobile ballistic missile systems for its land-based nuclear forces, its deployment of a sea-based nuclear deterrent offers the most secure theoretical nuclear counterstrike capability. This is because submarines are harder to pin down and are therefore most likely to survive enemy’s first strike to give China the ability to counterstrike even if all the land-based nuclear assets have been destroyed.


In reality, however, China currently faces limitations in the deployment of Type 094 JIN-class SSBNs from Hainan Island because of the high level of noise the submarines generate while under sail. Even though they appears to be a major improvement over China’s first-generation XIA, an unclassified report by the Office of Naval Intelligence indicates they are somewhat noisier than Russia’s older Delta III SSBNs.[22Given that Japan and the US most likely have deployed a variety of submarine surveillance systems as well as sophisticated anti-submarine assets throughout the East China Sea and the western Pacific, the JIN-Class SSBNs can be easily targeted. They therefore cannot operate independently in conditions of high intensity conflict. Moreover, the maritime geography of the East and South China Sea offers limited access channels to the Pacific Ocean for open-ocean nuclear deterrence patrols. Taken together, these factors constrain China’s deployment of its sea-based nuclear deterrent in the near term.


To mitigate these constraints, China is said to have adopted a “bastion” strategy that guided Soviet SSBN deployment during the Cold War. Under that strategy, PLAN keeps its SLBM force safe close to home within the South China Sea while maintaining a credible nuclear counterstrike. At the same time, China is pinning its hope on technical advances to accelerate the development of its anti-submarine warfare capabilities in order to pose a genuine threat to American attack submarines lurking in the water off its coast. There are also talks about China constructing military bases on disputed areas of the Spratly Islands in the South China Sea. These military bases would provide expanded areas of protection and support for Type 094 patrols.[23]


Currently, China may be developing a quieter variant of the Type 094 (the Type 094A) and a longer-range ballistic missile based on the JL-2 (sometimes termed the JL-2A). PLAN is also reported to be developing a fourth-generation the Type 096 each to be equipped with 24 next-generation intercontinental SLBMs, the JL-3.[24] Meanwhile, recent media report indicates that China may have initiated its first sea-based nuclear deterrence patrols with Jin-Class ballistic missile nuclear submarines (SSBNs) in 2017. If true, this has come approximately 60 years after the initiation of China’s SLBM program, 35 years after China’s first successful test launch of a ballistic missile from a submerged submarine, and about 30 years after the initiation of the Type 094 SSBN program. This time scale underscores the incremental pace of development for China’s SLBM capability. In contrast, the United States initiated its own SLBM program (Polaris) in the mid-1950s and first deployed the Polaris system about 5 years later in 1960.[25]

Closing of the Technological Gap


The improvements of Chinese submarines, in terms of both quantity and quality, are raising concerns in the West over how quickly China is catching up.


During the 1990s, with the ending of the Cold War, Russia withdrew most its submarines from service while the US steadily shrank its attack submarine force from 102 boats in 1987 to the current 52. The decline followed repeated revisions of the Navy's force structure plans since the Reagan-era. In 1992, for example, the Joint Chiefs of Staff (JCS) force-level study reduced the goal to 55. This was followed by the 1997 Quadrennial Defense Review which lowered the bar further to 50 SSNs.[26] By 2029, the number of attack boats is projected to reduce to 41.


In contrast, PLAN‘s operational undersea force currently has 63 vessels – 5 SSNs, 4 SSBNs, and 54 SSKs of which 30 are the newer SONG-class and YUAN-class boats with diesel-electric AIP system. Based on DOD’s estimates, PLAN’s undersea force will grow to between 69 and 78 submarines by 2020.[27] Another US government agency, the Office of Naval Intelligence (ONI), provided a more precise projection of 74 submarines in 2020, including 11 nuclear-powered boats and 63 non-nuclear-powered boats.[28]


The US Navy’s top leadership agrees—submarines remain the single greatest threat to the carrier and the surface fleet.[29] China’s submarines are armed with one or more of the following: ASCMs, wire-guided and wake-homing torpedoes, and mines. Eight of the 12 KILOS purchased from Russia (presumably the ones purchased more recently), for example, are armed with the highly capable Russian-made SS-N-27 Sizzler ASCM. Indigenously built subs, on the other hand, will be outfitted with China’s supersonic YJ-18 ASCM regarded by the Pentagon as one of the most lethal anti-ship weapons. Chinese analysts have called the YJ-18 “the most perfect anti-ship cruise missile.” With the ASCMs and ASBMs stealing the limelight, it is easy to overlook the potency of wake-homing torpedoes which analysts say are also a concern because they can be very difficult for surface ships to counter and therefore are among the only threats that can actually sink an aircraft carrier. In addition, SHANG-class SSNs may also carry land-attack cruise missiles (LACMs) thus allowing them to attack also ground targets.


Quality wise, some US analysts see the new SHANG-class Type 093B SSN on par with the US Navy’s Improved LOS ANGELES-class boats while the yet to come SHANG-class Type 095 SSGN are only slightly less capable than the SEAWOLF and VIRGINIA-classes premier U.S. Navy attack submarines. This means that US Navy will be facing-off against a Chinese submarine fleet that is nearly twice its size but not much less technically capable. The serious risk here is that the quality advantage the US Navy assumes it has may not be enough to overcome the quantity disadvantage from the declining number of submarines. This is especially so if PLAN concentrates its deployment in Asia Pacific in the event of crisis while the American submarines are thinly distributed to meet US’ global commitments.[30]


More important, Chinese naval engineers have gone beyond just reverse engineering and copying to come up with their own innovative solutions.


For example, China has recently developed a new Integrated Electrical Propulsion System (IEPS) its top naval engineer claims will put PLAN ‘way ahead’ of the USN. When used with quieter reactors like the Type 095’s reported natural circulation reactor, the revolutionary shaftless ultra-quiet engine can drastically reduce the acoustic signature of any nuclear-powered submarines. Hence, expect the IEPS to be installed on the latest nuclear-powered Type 095 SSNs still under construction as well as on China’s next generation strategic nuclear submarine, the Type 096 SSBNs, slated to begin construction only in the 2020s.[31]


In June 2017, the Chinese Academy of Sciences hailed another breakthrough, this time a magnetometer that measures magnetic fields based on a superconducting quantum interference device, or SQUID. Since the WWII, magnetometers have been used to detect submarines by measuring an anomaly in Earth’s magnetic field – like one caused by a massive hunk of metal. Magnetometers in use today’s can only detect a submarine at fairly short range. The use of a new magnetometer based on a SQUID could enable a sub to be detected from 6 kilometres away. This would be catastrophic for NATO submarines, which have been honed to run ever more quietly, using clever technology that prevents them from being heard or detected on sonar. Their magnetic signature is much harder to eliminate. Not everyone is convinced though that the Chinese magnetometer is ready for deployment. Notably, the US Navy gave up work on superconducting magnetometers to pursue less sensitive but more mature technologies.[32]


Finally, China is also working on a project called the “Underwater Great Wall” to extend its offshore surveillance zone. It involves the China State Shipbuilding Corp. (CSSC), which is one of China’s top shipbuilding and defence groups that builds virtually all PLAN’s warships, laying a string of submerged sensors, buoys and drone submarines. The CSSC model appears to be a vastly advanced and comprehensive version of the Sound Surveillance System (SSS) that had accorded the US a significant advantage in countering Soviet submarines during the Cold War. The SSS was comprised of an array of hydrophones on the ocean bottom connected by undersea cables along the entire US East Coast to onshore processing centers.[33]


Currently, US Navy submariners are closely watching advances in Chinese submarine forces which still lag in terms of capabilities, stealth and decades of experience the Americans have operating around the world. However, China is making rapid strides in closing the gaps. The embarrassing 2006 incident of the undetected PLAN SONG-class attack submarine surfacing near the US Kitty Hawk (i.e. inside the carrier escort screen) is a case in point. One way to prevent that from happening again is to have the service’s attack submarine (SSN) force remains dominant in the undersea realm. With China’s superiority in number and closing quality gap, however, that seems increasingly harder to achieve. [34]



PLA has come a long way from what many observers called a “junkyard army” to a modern and professional fighting force. As recent as 2012, the US Congressional Research Service (CRS) reports that China “continues to exhibit limitations or weaknesses in several areas, including capabilities for sustained operations by large formations in distant waters, joint operations with other parts of China’s military, C4ISR systems, anti-air warfare, anti-submarine warfare, [and] a dependence on foreign suppliers for certain key ship components.”[35] By 2017, however, a similar CRS report declares that “China continues to invest in foreign suppliers for some propulsion units, but it is becoming increasingly self-sufficient”.


Looking ahead, as the PLAN narrowed the technological gaps, production will became more indigenous and more efficient. This will help to bring about major qualitative improvements. Overall, although PLAN still faces some capability gaps in key areas, it is emerging as an increasingly well-equipped and competent force.[36]

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[1] See Defencyclopedia. (2014). “Anti-Submarine Warfare (Part-2) : Diesel-Electric Submarines.” April 27, 2014.

[2] See Defencyclopedia. (2016). “Explained: How Air Independent Propulsion (AIP) Work!”. July 6, 2016.

[3] See Defencyclopedia. (2014). “Anti-Submarine Warfare (Part-3) : Nuclear Submarines.” May 4, 2014.

[4] See Mackenzie Eaglen and Jon Rodeback. (2010). “Submarine Arms Race in the Pacific: The Chinese Challenge to U.S. Undersea Supremacy.” February 2, 2010.

[5] See Elaine M. Grossman. (2012). “Pentagon Unveils New Plan for Conventional Submarine-Based Ballistic Missiles.” NTI. January 27, 2012.

[6] McDevitt, Michael, “The PLA Navy’s Anti-access Role in a Taiwan Contingency,” in Phillip Saunders, Christopher Yung, Michael Swaine, and Andrew Nien-Dzu Yang, eds., “The Chinese Navy: Expanding Capabilities, Evolving Roles.” Washington, D.C.: National Defense University Press, 2011, pp. 191–214.

[7] See Department of Defense. (2016). “Annual Report to Congress: Military and Security Developments Involving the People’s Republic of China 2016.”

[8] See DOD. (2017). Pg 27.

[9] See Robert Farley. (2015). “Should the U.S. Military Fear China's Underwater Atomic Arsenal?” National Interest. November 1, 2015.

[10] See Dave Majumdar. (2016). “Why the U.S. Navy Fears Russian and Chinese Submarines.” National Interest. June 27, 2016.

[11] See MAREX. (2017). "Leaked Slides Yield Clues to Chinese Navy's Ambitions." October 20, 2017.

[12] See Peter Coates. (2013). “China Selling Two Type 035 Ming0class Submarines to Bangladesh.” Submarine Matters. December 24, 2013.

[13] ibid

[14] See “Type 39 / Song Class Attack Submarine.”

[15] See Ronald O’Rourke. (2017). Pg 17.

[16] See “Type 039 Song S20 Class.” See Michael GoldFarb. (2007). “Red China & Red Lines.” Weekly Standard. January 12, 2007.

[17] See Sebastien Roblin. (2016).

[18] See also Lyle Goldstein. (2015A). “Emerging From The Shadows,” U.S. Naval Institute Proceedings, Vol. 14I/4/1,346. April 201. : 30-34.  

[19] See Ronald O’Rourke. (2017). Pg 16.

[20] See Sebastien Roblin. (2016). “China Has Built the Biggest and Baddest Conventional Submarine in the World.” December 5, 2016.

[21] See Missile Threat. (2016). “Ju Lang-2 (JL-2/CSS-NX-14)”. Centre for Strategic and International Studies.

[22] See Benjamin S. Purser, Michael S. Chase. "Waypoint or Destination? The Jin-Class Submarine and China’s Quest for Sea-Based Nuclear Deterrence." Jamestown Foundation. August 3, 2012. 

[23] See Renny Babiarz. (2017). “China’s Sea-Based Nuclear Deterrent: Incremental Advances and Perennial Limitations.” CPI Analysis. April 5, 2017.

[24] See Renny Babiarz. (2017). “China’s Nuclear Submarine Force.” The Jamestown Foundation. July 21, 2017; Dave Majumdar. (2017). “Does China Have a Nuclear Submarine That Could Beat the U.S. Navy?” National Interest. February 13, 2017; See Minnie Chan. (2017). “Why Chinese submarines could soon be quieter than US ones

[25] See Renny Babiarz. (2017). “China’s Sea-Based Nuclear Deterrent: Incremental Advances and Perennial Limitations.” CPI Analysis. April 5, 2017.

[26] See Mackenzie Eaglen and Jon Rodeback. (2010).

[27] See Bill Gertz. (2017); DOD. (2017). Pg 24.

[28] See ONI Report. (2015). Pg 18

[29] See Dave Majumdar. (2016). “Why the U.S. Navy Fears Russian and Chinese Submarines.” National Interest. June 27, 2016.

[30] ibid

[31] See Minnie Chan. (2017). See Jeffrey Lin and P.W. Singer. (2017). “China's new submarine engine is poised to revolutionize underwater warfare.” Popular Science. June 2, 2017; See Brian Wang. (2017). “China claims successful Magnetic submarine and ship propulsion tests.” NextBigFuture. October 29, 2017.

[32] See David Hambling. (2017). “China’s quantum submarine detector could seal South China Sea.” New Scientist. August 22, 2017.

[33] See Sarosh Bana. (2016). “China’s Underwater Great Wall.” Washington Times. August 30, 2016.

[34] See Dave Majumdar. (2016). “Why the U.S. Navy Fears Russian and Chinese Submarines.” National Interest. June 27, 2016.

[35] See Ronald O’Rourke. (2017). “China Naval Modernization: Implications for U.S. Navy Capabilities— Background and Issues for Congress.” Washington, D.C.: Congressional Research Service, RL33153, October 17, 2012. Pg 3-4.

[36] See ONI. (2015). Pg 13.

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