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The Deep Ocean: Seabed Warfare and the Defense of Undersea Infrastructure, Pt. 2

Read Part One here.

By Bill Glenney

Concepts from the CNO SSG

From 1998 to 2016, the CNO Strategic Studies Group (SSG) consistently recognized and accounted for the challenge of cross-domain maritime warfare, including the deep ocean. The Group generated several operational concepts that would give the Navy significant capabilities for the deep ocean part of the maritime battle.

Vehicles and Systems

Within the body of SSG concepts were reasonably detailed descriptions of a range of unmanned underwater vehicles, undersea sensors, and undersea weapons such as the towed payload modules, extra-large UUVs, logistics packages, and bottom-moored weapons. All would use the seabed and undersea for sensing, attacking, and sustaining in support of maritime forces.

One vehicle worth discussing is the armed UUV for single-sortie obstacle neutralization that would provide the Navy with the capability to counter armed UUVs, or conduct search for and clearance of fixed and mobile mines without the need for local air/surface superiority, or a manned support ship.1 It could plausibly do so at tactical sweep rates higher than today’s MCM forces. This can be achieved well before 2030, yet this capability is something neither the existing nor planned MCM forces can do.

The SSG XXXII concept can be achieved by integrating the following capabilities on the conceptualized extra-large UUV (XLUUV):

  • A synthetic aperture sonar – a capability the Navy had in 2013 
  • Automatic target-recognition software – a capability the Navy was developing
  • A 30 mm cannon that shoots super-cavitating rounds – a capability previously funded but not developed by the Navy

But, instead of focusing on the vehicles, there are two examples of operational-level concepts that exploit these vehicles and systems in recognition of the fact that the deep ocean is a critical yet misunderstood and underutilized part of maritime warfighting. 

Blitz MCM

In 1999, the SSG generated a concept called “Blitz MCM.”2 This work has stood the test of time technically and analytically, but has not been adopted by the Navy. And, while the SSG described it in terms of mine countermeasures, this same approach can be applied to deep ocean warfighting and the defense of undersea infrastructure.

At its most basic level, Blitz MCM resulted from the recognition that sensor performance in the undersea was not going to improve significantly from a tactical perspective over the period of 2000-2030. For clarity, yes, the accuracy of various undersea sensors has improved routinely, providing accuracy down to fractions of a meter and able to produce fairly detailed pictures of objects. But the effective range of these sensors has not and will not dramatically increase, still being measured in hundreds and maybe a thousand yards at best. These short ranges preclude their use as a single sensor when it comes to tactical maneuver in the maritime environment.

The SSG solution was to use large numbers of these individual sensors.

In order to enable the rapid maneuver by maritime forces, the force must be able to conduct in-stride mine reconnaissance and clearance of approach routes and intended areas of operations. In order to avoid lengthy operational pauses to search large areas and neutralize mines or armed UUVs or undersea explosives, Blitz MCM uses relatively autonomous UUVs that rely on sensing technology only moderately advanced beyond that available to the fleet 20 years ago. However, unlike today’s operations where small numbers of mine-hunting vehicles and aircraft are involved, Blitz MCM relies on the deployment of large numbers of unmanned vehicles out ahead of the force to rapidly work through the areas of interest to find, tag, or clear threats. Hundreds of small UUVs can work together as an intelligent swarm to clear thousands of square miles of ocean per day.

In some cases, based on the information provided by the vehicles, alternate approach routes or operating areas would be chosen, and the movements of closing units can be rapidly redirected accordingly. In other cases, the required paths will be cleared with a level of confidence that allows force elements to safely continue through to their intended operating areas.

As illustrated in figure 7, UUV-Ms use conformal, wide-band active/passive sonar arrays, magnetic sensors, electric field sensors, blue-green active/passive lasers, and trace chemical “sniffing” capabilities to detect mines. Onboard automatic target recognition capabilities are essential to the classification and identification effort. Acoustic and laser communications to near-surface relays or seabed fiber-optic gateways maintain connectivity.

Figure 7 – Mine Hunting and Clearance Operations (CNO SSG XIX Final Report)

Unmanned air vehicles are critical in their role as UUV carriers, especially when rapid deployment of UUVs is required across a large space. UCAV-Ms contribute to the effort with their mine-hunting lasers. They also serve as communications gateways from the “swimmer” UUVs to the network.

The UUV-Ms will generally operate in notional minehunting groups of several dozen to over a hundred vehicles. Teams of vehicles will swim in line abreast formations or in echelons with overlapping fields of sonar coverage. Normally they will swim at about 8-10 knots approximately 50 feet above the bottom. Following in trail would be additional UUVs assigned a “linebacker” function to approach closely and examine any suspicious objects detected. Tasking and team coordination will be conducted by the UUVs over acoustic or laser modems. Once a linebacker classifies and identifies a probable mine, its usual protocol will be to report the contact, standoff a short distance, and then send in a self-propelled mine clearing charge to destroy or neutralize the mine. Each UUV-M could carry approximately 16 of these micro-torpedoes. When one linebacker has exhausted its supply, it will automatically trade places with another UUV-M in the hunting team.

Rapid neutralization of mine threats is key to the clearance effort. Today, this dangerous task is often performed by human divers. 

Blitz MCM uses a “leapfrog laydown” of UUV-Ms, as illustrated in Figure 8. Analogous to the manner that sonobuoys are employed in an area for ASW coverage, the force would saturate an area of interest with UUV-Ms to maximize minehunting and clearance capabilities. Once dropped into the water, the UUV-Ms quickly form into echelons and begin their hunting efforts. Navigation and communication nodes will be dropped along with the Hunter UUV-Ms.

Figure 8 – Leapfrog Laydown of UUVs (CNO SSG XIX Final Report)

Large delivery rates will be possible with multiple sorties of UCAV-Ms each dropping two to four UUV-Ms on a single load and then rapidly returning with more. Upon completion of their missions, the Hunter UUV-Ms will be recovered by UCAVs or USVs and returned to the appropriate platforms for refueling, servicing, and re-deployment.

First order analysis indicates that with approximately 150 UUV-Ms in the water and a favorable oceanographic and bottom environment, reconnaissance and clearance rates of about 6,000 to 10,000 square miles per day (a 20-mile wide swath moving at 12-20 knots) should be achievable. This capability is several orders of magnitude over current MCM capabilities.

Naval Warfighting Bases

The SSG XXXII concept called Naval Warfighting Bases3 requires the Navy to think about sea power and undersea dominance in an entirely new way. And this new thinking goes against the grain of culture and training for most naval officers and is unconventional in two ways:

  • First, in Naval Warfighting Bases, forces ashore will have a direct and decisive role in establishing permanent undersea superiority in high interest areas
  • Second, “playing the away game” – the purview of forward deployed naval forces − is not sufficient to establish and sustain undersea dominance at home

As shown in Figure  9, afloat forces – CSGs, ESGs, SAGs, and submarines – do not have the capacity or the capabilities to establish permanent undersea dominance of the waters adjacent to the U.S. homeland and its territories (shown in yellow) and of key maritime choke points (shown with white circles), while simultaneously reacting to multiple crisis spots around the world (shown in red). The Navy must discard its current model of undersea dominance derived solely from mobile, forward deployed at-sea forces and replace it with one that is more inclusive − one that looks beyond just afloat forces. This new model must capitalize on the permanent access the Navy already has from shore-based installations at home and abroad (shown with yellow stars).

Figure 9 – Global Requirements for Undersea Superiority

Naval Warfighting Bases builds on detailed local understanding of the undersea, coupled with the projection of combat power from the land to control the sea; thereby providing permanent undersea dominance to defend undersea critical infrastructure near the homeland, protect major naval bases and ports of interest, and to control strategic chokepoints. Naval Warfighting Bases also provides the critical benefit of freeing up afloat Navy forces for missions only they can conduct.

At home, the U.S. Navy could establish something called an Undersea Defense Identification Zone, akin to the Air Defense Identification Zone, to detect and classify all deep sea contacts prior to their entry into the U.S. exclusive economic zone (EEZ). By enhancing the capabilities of key coastal installations, the Navy will transform each into a Naval Warfighting Base. The base commander will be a warfighter with the responsibility, authority, and capability to establish and maintain permanent undersea superiority out to a nominal range of 300 nautical miles seaward from the base to include the majority of U.S. undersea and maritime critical infrastructure.

Figure 10 – Undersea Defense Identification Zones Provide Permanent Undersea Superiority

Base commanders will have the capability to detect and track large numbers of contacts as small as wave-glider sized UUVs. Each Naval Warfighting Base will have a detachment of forces to actively patrol its sector. Naval Warfighting Base commanders will be able to maintain continuous undersea understanding, enabling control of the deep ocean.

Naval Warfighting Base commanders will also have an integrated set of shore-based and mobile weapons systems with the capability to neutralize adversary undersea systems, such as UUVs, mines, and sensors. Naval Warfighting Base commanders will be capable of disabling or destroying all undersea threats in their sector, employing armed unmanned systems, and employing undersea warfare missiles fired from ashore.

An undersea warfare missile is a tactical concept that combines a missile and a torpedo, similar to modern ASROC missiles. The missile portion would provide the range and speed of response, while the torpedo portion would provide the undersea killing power. Broadly integrating undersea warfare missiles into a variety of platforms would provide a tremendous capability to cover larger areas without having to tap manned aviation or surface assets for weapon delivery. These missiles would provide responsive, high volume, and lethal capabilities. And they could be fired from land installations, submarines, surface combatants, and aircraft.

As practiced today, waterspace management (WSM) and prevention of mutual interference (PMI) result in a highly centralized authority, and extremely tight control and execution for undersea forces. This type of C2 would prevent undersea forces and Naval Warfighting Bases from becoming operational realities, and it would eliminate the warfighting capabilities from a balanced force of manned and unmanned systems. Undersea dominance is not possible without more deconflicted C2. The submarine force in particular must get over the fear of putting manned submarines in the same water as UUVs, and develop the related procedures and tactics to do so.

Defense of Undersea Infrastructure as a Navy Mission

As early as 2008 in their final report to the CNO, after having spent a second year of deep study on the convergence of sea power and cyber power, the SSG gave the CNO the immediately actionable step to:

take the lead in developing the nation’s deep seabed defense (emphasis in the original), given the absolute criticality of seabed infrastructure to cyberspace. Challenge maritime forces and the research establishment to identify actions and technologies that will extend maritime domain awareness to the ocean bottom, from the U.S. coastline to the outer continental shelf and beyond. Prepare now for a future in which U.S. commercial exploitation of the deep seabed – including the Arctic – is both commercially feasible and urgently required, making deep seabed defense a national necessity.”4

In 2008 and again in 2013, Navy leadership offered that there is no requirement for the U.S. Navy to defend undersea infrastructure except for some very specific, small area locations.5 In this context, the term requirement is as it relates to formally approved DON missions, functions, tasks, budgeting and acquisition, but not actual warfighting necessity.


The force must have the capabilities to sense, understand, and act in the deep ocean. The capabilities to do so are already available to anyone with a reasonable amount of money to buy them. Operationally speaking, hiding things on the seabed is fairly easy. On the other hand, finding things on the seabed is relatively difficult unless one is looking all the time, and has an accurate baseline from which to start the search and compare the results. The deep ocean presents an “area” challenge and a “point” challenge simultaneously, and both must be addressed by the maritime force. Understanding the deep ocean and fighting within it is also a matter of numbers and time – requiring lots of vehicles, sensors, and time.

The U. S. Navy is not currently in the game. With a variety of unmanned vehicles, sensors, and weapons coupled with Blitz MCM, Naval Warfighting Bases, and making undersea infrastructure defense a core U.S. Navy mission, the fleet can make the deep ocean – the entire undersea and seabed – a critical advantage in cross-domain warfighting at sea.

Professor William G. Glenney, IV, is a researcher in the Institute for Future Warfare Studies at the U. S. Naval War College.

The views presented here are personal and do not reflect official positions of the Naval War College, DON or DOD.


1. Chief of Naval Operations Strategic Studies Group XXXII Final Report, Own the Undersea (March 2014, Newport, RI), pp 4-6 to 4-9.

2. Chief of Naval Operations Strategic Studies Group XIX Final Report, Naval Power Forward (September 2000, Newport, RI), pp 6-8 to 6-12.

3. Chief of Naval Operations Strategic Studies Group XXXII Final Report, Own the Undersea (March 2014, Newport, RI), pp 2-15 to 2-20.

4. Chief of Naval Operations Strategic Studies Group XXVII Final Report Collaborate & Compel – Maritime Force Operations in the Interconnected Age (December 2008), pp 8-1 and 8-4.

5. Author’s personal notes from attendance at SSG XXVII briefings to the CNO on 19 July 2008 and SECNAV on 24 July 2008, and SSG XXXII briefing to the CNO on 25 July 2013.

Featured Image: Pioneer ROV (Blueye Robotics AS)

The Deep Ocean: Seabed Warfare and the Defense of Undersea Infrastructure, Pt. 1

By Bill Glenney


Given recent activities by the PLA(N) and the Russian Navy, the matters of seabed warfare and the defense of undersea infrastructure have emerged as topics of interest to the U. S. Navy.1,2 Part One of this paper presents several significant considerations, arguably contrary to common thinking, that highlight the challenges of bringing the deep sea and benthic realm into cross-domain warfighting in the maritime environment. Part Two presents three warfighting concepts drawn from the body of work done by the CNO Strategic Studies Group (SSG) that would give the Navy capabilities of value for the potential battlespace.

The Deep Ocean Environment

For clarity the term “deep ocean” will be used to cover the ocean bottom, beneath the ocean bottom to some unspecified depth, and the ocean water column deeper than about 3,000 feet.3 The deep ocean is where the U.S. Navy and the submarine force are not. Undersea infrastructures are in the deep ocean and on or under the seabed for various purposes.

How does the maritime fight on the ocean surface change when there must be a comparable fight for the deep ocean? In the maritime environment, it is long past time for the U.S. Navy to be mindful of and develop capabilities that account for effects in, from, and into the deep ocean, including effects on the ocean floor. Cross-domain warfighting demands this kind of completeness and specificity. As the Army had to learn about and embrace the air domain for its Air-Land battle in the 1980s, the Navy must do the same with the deep ocean for maritime warfare today and for the future.

However, the current frameworks of mine warfare, undersea warfare, and anti-submarine warfare as practiced by the Navy today are by no means sufficient to even deny the deep ocean to an adversary let alone control the deep ocean.  To “own” a domain, a force must have the capability to sense and understand what is in and what is happening in that domain. The force must also have the capability to act in a timely manner throughout that domain.

Today, the Navy and many nations around the world have radars and other sensors that can detect, track, and classify most of anything and everything that exists and happens in the atmosphere from the surface of the ocean and land up to an altitude of 90,000 feet altitude or higher, even into outer space. The Navy and many nations also have weapons – on the surface and on land, and in the air – that can act anywhere within the atmosphere. Some nations even have weapons that can act in the atmosphere from below the ocean surface. In short, with regard to the air domain, relevant maritime capabilities abound, including  fixed or mobile, unmanned or manned, precise or area. Naval forces can readily affect the air domain with capabilities that can cover the entire atmosphere.

But the same cannot be said for the deep ocean. Figure 1 below is based on information drawn from unclassified sources. Consider this depiction of the undersea in comparison with the air domain. Notice that there is a lot of light blue space – space where the Navy apparently does not have any capability to sense, understand, and act. The Navy’s capability to effect in, from, and into the deep ocean is at best extremely limited, but for the most part non-existent. Capabilities specifically relative to the seabed are even less, and with the Navy’s mine countermeasures capabilities also being very limited. What systems does the Navy have to detect unmanned underwater vehicles at very deep depths? What systems does the Navy have to surveil large ocean areas and the resident seabed infrastructure? What systems does the Navy have to act, defend, or attack, in the deep ocean?

Figure 1 – The Deep Ocean

Arguably, the Navy has built an approach to maritime warfighting that dismisses the deep ocean, and done so based on the assumption that dominating the top 3,000 feet of the waterspace is sufficient to dominating the entire waterspace – ocean floor to ocean surface. Undersea infrastructure is presumably safe and protected because the ceiling over it is locked up.

However, the force must have the capabilities to sense, understand, and act in the deep ocean.

While the assumption for dominating the deep ocean by dominating the ceiling may have been useful in the past, it clearly is no longer valid. In the past, it was very expensive to do anything in the deep ocean. The technology was not readily available, residing only in the hands of two or three nations or big oil companies. This no longer holds true. The cost of undersea technology for even the deepest known parts of the ocean has dropped dramatically, and also widely proliferated. If one has a couple hundred million dollars or maybe a billion dollars, they can sense, understand, and act in the deep ocean without any help from a nation or military. Unlike the U.S. government-funded search for the SS Titanic by Robert Ballard, Microsoft co-founder Paul Allen independently found USS Indianapolis in over 15,000 feet of water in the Philippine Sea. The capabilities to sense, understand, and act in the deep ocean are available to anyone with a reasonable amount of money to buy them.

Figure 1 is misleading in one perspective. At the level of scale in figure 1, the ocean floor looks flat and smooth. If something is placed on the ocean bottom, such as a towed payload module, a logistics cache, sensors, or a weapon system, could it be easily found?

Figure 2 is a picture of survey results from the vicinity of the Diamantina Trench approximately 700 miles west of Perth, Australia in the Indian Ocean. The red line over the undersea mountain is about 17 miles in length. The water depth on the red line varies from 13,800 feet to 9,500 feet as shown on the right.4

Figure 2 – Diamantina Trench

Consider figure 3. The red line is just under three miles in length. The depth variation ranges from 12,100 feet to 11,900 feet.5 These figures provide examples of evidence that the abyssal is not featureless. The assumption of a flat and smooth ocean floor is simply wrong, and severely understates the challenge of sensing and acting in the deep sea.

Figure 3 – A Closer View in the Diamantina Trench

How hard would it be to find a standard-sized shipping container (8ft x 8ft x 20ft or even 40ft) on this floor? It could be incredibly difficult, requiring days or weeks or even months with many survey vehicles, especially if the area had not been previously surveyed. This is a lesson the U. S. Navy learned in the Cold War and has long since forgotten from its “Q routes” for port access. And it would be harder still if one were purposefully trying to hide whatever they placed on the ocean floor, such as in the pockmarks of figure 3.

Based on reported results from a two-year search for Malaysian Airlines flight MH-370, approximately 1.8 million square miles of the ocean floor were searched and mapped to a horizontal resolution on the order of 100 meters and vertical resolution of less than one meter.6 Yet, the plane remains unlocated.

Hiding things on the seabed is fairly easy, while finding things on the seabed is incredibly difficult. Unless one is looking all the time, and has an accurate baseline from which to start the search and compare the results, sensing in the deep sea is significant challenge. The next consideration is that of the matter of scale of the geographic area and what resides within it. This is what makes numbers matter.

Figure 4 provides a view of the Gulf of Mexico covering about 600,000 square miles in area and with waters as deep as 14,000 feet. There are about 3,500 platforms and rigs, and approximately 43,000 miles of pipeline spread across the Gulf.

Figure 4. – The Gulf of Mexico (National Geographic)

Of note, the global economy and worldwide demands for energy have caused the emergence of a strategic asymmetry exemplified by this figure. China gets most of its energy imports by surface shipping which is vulnerable to traditional anti-shipping campaigns. The U. S. gets much of its energy from undersea systems in the Gulf of Mexico. While immune from anti-shipping, this infrastructure is vulnerable to seabed attack. In late 2017, the Mexican government leased part of their Gulf of Mexico Exclusive Economic Zone seafloor to the Chinese for oil exploration.

Figure 5 provides a depiction of global undersea communication cables with some 300 cables and about 550,000 miles of cabling.

Figure 5 – Global Undersea Telecommunications Cables

Figure 6 provides a view of the South China Sea near Natuna Besar. This area is about 1.35 million square miles with waters as deep as 8,500 feet. Recall that in the two-year search for Malaysian Air flight MH 370 they surveyed only 1.8 million square miles, and did so in a militarily-benign environment. 

Figure 6 – The South China Sea

The deep ocean demands that a maritime force be capable of surveilling and acting in and over large geographic areas just like the ocean surface above it. Undersea infrastructure is already dispersed throughout those large areas. In addition, because the components of undersea infrastructure are finite in size, the deep ocean also demands that a maritime force be capable of surveilling and acting in discrete places. While it is arguable that defense in the deep ocean is a wide-area challenge and offense is a discrete challenge, the deep ocean demands that a maritime force be capable of doing both as part of the maritime battle. Therefore, the deep ocean presents an “area” challenge and a “point” challenge simultaneously, and both must be addressed by maritime forces.

In addition, the size of the area and the number of points of interest means that a dozen UUVs or a couple of nuclear submarines are not in any way sufficient to address the maritime warfighting challenge of defending the deep ocean and undersea infrastructure of this scale. Furthermore, the situation is exacerbated by systems and vehicles in the deep ocean above the seabed. The threat is not a few, large, manned platforms, but many small unmanned vehicles and weapons.

The historical demarcation among torpedoes, mines, and vehicles is no longer productive except maybe for purposes of international law and OPNAV programmatics. Operationally and tactically, the differentiation is arbitrary and a distraction from operational thinking. The Navy should be talking in terms of unmanned systems – some armed or weaponized, and some not; some mobile and some not; some intelligent and some not. Torpedoes can easily become mobile, armed UUVs with limited intelligence. Mines can also become mobile or fixed UUVs with very limited intelligence.

In the course of the author’s research and in research conducted by the CNO SSG, there were no situations or considerations where reclassifying mines and torpedoes as UUVs was problematic with regard to envisioning war at sea. Doing so eliminated a significant tactical and operational seam and opened up operational thinking. The systems for the detection and neutralization of UUVs are the same as those needed to detect and neutralize torpedoes and mines, and the same for surveilling or attacking undersea infrastructure.


Ultimately, understanding the deep ocean and warfare in the deep ocean is a matter of numbers and time – requiring plenty of sensors, and plenty of time. Part Two will present three warfighting concepts drawn from the body of work done by the CNO Strategic Studies Group (SSG) that would give the Navy capabilities for the deep sea battlespace.

Professor William G. Glenney, IV, is a researcher in the Institute for Future Warfare Studies at the U. S. Naval War College.

The views presented here are personal and do not reflect official positions of the Naval War College, DON or DOD.


1. This article is based on the author’s remarks given at the Naval Postgraduate School Warfare Innovation Continuum Workshop on 19 September 2018. All information and conclusions are based entirely on unclassified information.

2. See for example Rishi Sunak, MP, Undersea Cables:  Indispensable, Insecure, Policy Exchange (2017, London, UK);  Morgan Chalfant and Olivia Beavers, “Spotlight Falls on Russian Threat to Undersea Cables”, The Hill, 17 June 2018 accessed at http://thehill.com/policy/cybersecurity/392577-spotlight-falls-on-russian-threat-to-undersea-cables;  Victor Abramowicz, “Moscow’s other navy”, The Interpreter, 21 June 2018 accessed at https://www.lowyinstitute.org/the-interpreter/moscows-other-navy?utm_source=RC+Defense+Morning+Recon&utm_campaign=314b587fab-EMAIL;  Stephen Chen, “Beijing plans an AI Atlantis for the South China Sea – without a human in sight”, South China Morning Post, 26 November 2018 accessed at https://www.scmp.com/news/china/science/article/2174738/beijing-plans-ai-atlantis-south-china-sea-without-human-sight;  and Asia Times Staff, “Taiwan undersea cables ‘priority targets’ by PLA in war”, Asia Times, 6 December 2017 accessed at http://www.atimes.com/article/taiwan-undersea-cables-priority-targets-pla-war.

3. Based on unclassified sources, manned nuclear submarines can operate to water depth of 1,000-1,500 feet, manned diesel submarines somewhat shallower, and existing undersea weapons to depths approaching 3,000 feet.

4. Kim Picard, et. al., “Malaysia Airlines flight MH370 search data reveal geomorphology and seafloor processes in the remote southeast Indian Ocean,” Marine Geology 395 (2018) 301-319, pg 316.

5. Kim Picard, et. al., “Malaysia Airlines flight MH370 search data reveal geomorphology and seafloor processes in the remote southeast Indian Ocean,” Marine Geology 395 (2018) 301-319, pg 317.

6. Kim Picard, Walter Smith, Maggie Tran, Justy Siwabessy and Paul Kennedy, “Increased-resolution Bathymetry in the Southeast Indian Ocean”, Hydro International, https://www.hydro-international.com/content/article/increased-resolution-bathymetry-in-the-southeast-indian-ocean, accessed 13 December 2017.

Featured Image: Deep Discoverer, a remotely operated vehicle, explores a cultural heritage site during Dive 02 of the Gulf of Mexico 2018 expedition. (Image courtesy of the NOAA/OER)

Chinese Evaluations of the U.S. Navy Submarine Force, Pt. 2

This article originally featured in The Naval War College Review in 2008 and is republished with permission. Read it in its original form here. Read Part One of the republication here.

By Gabriel Collins, Andrew Erickson, Lyle Goldstein, and William Murray

Sensors, Systems, Research, Development, and Training

American efforts at exploiting advancements in commercial off-the-shelf technology have received attention. One article observes that “the updated (COTS) CCS MK II [fire control] system is not only used on the Los Angeles and Ohio classes, but is also used on the new Seawolf and Virginia class submarines”;44 another points out that “92% of the hardware and 90% of the software used in non-publicly available projects in fact come from popular commercially available technologies.”45 China’s intense interest in the U.S. Navy’s use of COTS may stem in part from Beijing’s effort to develop a world-class commercial information technology industry and to incorporate its products into the PLA.

Chinese analysts also monitor American submarine sensor development. One article notes, “At present, the U.S. is the world leader in developing periscope technology and using it on its submarines.”46 U.S. efforts to bolster the submarine force’s mine warfare capabilities receive particular attention.47 Moves to develop and acquire the Long Term Mine Reconnaissance System (LMRS) have been noted, with one researcher stating that “the U.S. is now buying 8 long-range mine scouting systems to be put on the Los Angeles and Virginia class nuclear attack submarines.”48

Chinese observers pay fairly close attention to American submarine-related research and development efforts. For example, websites on Chinese naval matters frequently report on the awarding of Defense Advanced Research Projects Agency (DARPA) and Office of Naval Research (ONR) contracts.49 Chinese journals take advantage of these announcements and also scour the U.S. open press for sources that can be exploited. For example, a rather lengthy article in the June 2002 issue of 现代舰船 (Modern Ships) reprinted the “Submarine of the Future” briefing slides (complete with a logo in the upper left-hand corner of each) generated by the DARPA-sponsored, Lockheed Martin–led industrial consortium “TEAM 2020.” These slides depict futuristic hull forms, sonar configurations, propulsors, weapons storage ideas, interfaces for unmanned underwater vehicles, and other elements of advanced submarine designs and concepts.50 It seems that little, if any, publicly released information regarding U.S. submarine-related research and development escapes the attention of Chinese analysts.

In keeping with the technological dynamism of U.S. platforms and their constant improvement, Chinese analysts also credit the American submarine force with an extremely rigorous selection and training process for commanding officers. In a coauthored article in Modern Navy, Rear Admiral Yang Yi, a PLA expert on the United States and former naval attaché in Washington, emphasizes that “the U.S. Navy’s selection process for the commanding officers of nuclear submarines is very strict.” Yang details the numerous education and training programs that successful candidates must attend, as well as the periodic qualifying tests they must undergo. A major emphasis of his article is the extent to which submarine commanders must periodically update their “specialized [technical] knowledge.”51

Historical Issues

Although China is emerging as a submarine power, its submarine force, and indeed its navy overall, generally lacks blue-water experience, to say nothing of a combat history. Of course, this paucity of experience stands in stark contrast to the U.S. submarine force, and PLA Navy analysts are acutely aware of that disparity. In fact, Chinese naval analysts have expressed particular admiration for the record of American submarines in World War II, pointing out that “the U.S. submarine force had the fewest losses” of any major submarine force “but had high combat effectiveness. According to statistics, the U.S. submarine force destroyed 1,314 enemy ships during the war.”52 Moreover, Chinese sources indicate an appreciation for the accumulated knowledge that the U.S. Navy has achieved through decades of intense submarine operations. Another Chinese source observes: “The U.S. is a country with 100 years of experience in building submarines, and with so many years of experience the USN constantly emphasizes the ability of a submarine to take punishment [and survive].”53

While there are numerous Chinese writings on the U.S. Navy’s submarine force’s campaign against Japan, this article focuses on the Chinese perceptions of American submarine operations during the Cold War. Some of the observations made in this context may explain aspects of contemporary PLA Navy submarine doctrine. For example, an article in Modern Ships relates an anecdote of a “Soviet Type 627 [known in the West as “November”] nuclear attack submarine [that] once went all out in a race with a U.S. Navy aircraft carrier, revealing the Soviet attack submarine’s capabilities. [This revelation] apparently has had a major impact on the development of a new class of American submarines.”54 This appraisal of the peacetime interaction between the two navies may suggest that overly aggressive tactics employed by the Soviet Navy yielded too much information to the U.S. Navy. In general, it is quite clear that Chinese sources understand that a “main mission of [U.S.] nuclear attack submarines [during the Cold War] was to deal with the Soviet Navy’s SSBNs.”55

With respect to the Cold War at sea, one Chinese book published in 2006 is worthy of particular note.56 The translation of a Russian book, Secrets of Cold War Undersea Espionage, states that “U.S. nuclear and conventional submarines would often lurk along the routes of Soviet warships, and even within Soviet territorial waters, conducting intelligence activities.”57 It is noted that “the SOSUS [Sound Surveillance] system substantially helped the U.S. to cope with the capabilities of the Soviet submarine force.”58 The subject of acoustic signatures is also raised: “In the ocean, there are simply too many sources of noise. . . . In order to cope with this problem, the U.S. decided to build an acoustic signature catalogue (resembling a fingerprint) for Soviet submarines.”59

Chinese ASW and the U.S. Navy Submarine Force

When considering Chinese views of the American submarine force, it is certainly relevant to consider how China appraises its own antisubmarine warfare forces. Generally, China considers its ASW forces to be weak. One Chinese naval analyst observes: “[Chinese] people are focused on China’s submarine force (both conventional and nuclear) development, but often neglect the threat we face from [U.S. Navy] submarines.”60 It is, moreover, suggested that “there is still a relatively large gap between [China’s] ASW technology level and that of the world’s advanced level.”61 In appraising the ASW capabilities of its own surface forces, another naval analyst notes, “Across the world, most naval ships are now equipped with towed array sonars, which has increased their ASW capabilities, but most of our ships only have hull mounted sonars.”62 Finally, there is a concern that these antisubmarine assets are themselves highly vulnerable: “Submarines can carry out ferocious missile attacks from tens or even 100–200km ranges, causing the submarine hunting vessels to become the hunted targets.”63

Chinese aerial ASW is also highlighted as a particular weakness. One Chinese analyst judges that the Z-9 helicopter lacks adequate range and internal space for the ASW mission.64 A second argues that while the Z-8 has better range and capacity, it is too big for most surface combatants to carry and chronic engine troubles have limited production.65 The Russian-import Ka-28 ASW helicopter is reported to be capable but few in numbers.66 As for Chinese maritime patrol aircraft, some designs have apparently been developed, including a variant of the Y-7 Fearless Albatross, but the outlook is said to remain bleak.67 Thus, one evaluation of Chinese aerial ASW concludes, “Our country at the present stage does not have an ASW maritime patrol aircraft . . . but the number of submarines in our peripheral seas is increasing, and their technological sophistication is also increasing. This contradiction is becoming more obvious every day, creating a grim situation.”68

In Chinese discussions of Russian ASW systems, there is a pointed recognition that the Soviets leaned heavily toward the use of tactical nuclear weapons (e.g., nuclear depth charges and torpedoes) in ASW operations.69 Tactical nuclear weapons are also mentioned in the context of mine warfare. An article in the July 2006 issue of Modern Navy, in discussing possible PLA Navy use of sea mines, suggests the potential combat value of nuclear-armed versions.70 It will be important to watch closely for any sign of Chinese efforts in this direction.

While the overall impression is that of Chinese ASW weakness, there is one notable exception. Significant prioritization appears to be given to the use of sea mines for the antisubmarine mission, as if to produce a “poor man’s ASW capability.”71 One discussion explains, “Because of a tremendous change in the maritime strategic environment, since the early 1990s the PLA has made mobile ASW sea mines a focal point of weapons development.” The analysis continues, “[China] is energetically undertaking the research mission [of] using [mobile ASW sea mines] against U.S. nuclear submarines.”72 The same discussion also hints at a review possible PLA Navy ASW role: “The major mission of self-guided sea mines is to isolate American nuclear submarines outside the First Island Chain.”73

It is noteworthy for the future development of Chinese antisubmarine warfare that hydroacoustics has been called a “key point” technology for state investment.74 The conventional wisdom has long been that the Chinese submarine force is focused entirely on the anti-surface ship mission. This assumption may have become outdated, perhaps especially after the PLA Navy received the last of eight new Kilo-class diesel submarines (and accompanying weaponry) from Russia in 2006. According to Professor Li Daguang of China National Defense University, these new Kilos have four missions: to blockade Taiwan, threaten carrier battle groups, employ land-attack cruise missiles as a “strategic weapon,” and “form an underwater threat to the U.S. nuclear submarine force.”75 There is also preliminary evidence that China is moving toward deploying antisubmarine rocket weapons on its newest surface combatants.76 This system is no “silver bullet,” as the Chinese would still have severe, perhaps insurmountable, targeting and cueing problems, but successful acquisition and deployment of ASROCs would extend the engagement range of Chinese ASW weapons significantly. It is also worth noting that Chinese sources discuss “many openly published dissertations concerning underwater targeting for a homing depth charge.”77

To reverse the equation: How do Chinese naval analysts appraise American ASW, and in particular the submarine force’s part in it? Clearly, the PLA Navy understands the overall centrality of SSNs in U.S. antisubmarine warfare. Thus an article in Modern Navy states: “The nuclear attack submarine . . . is the most effective tool for ASW.”78 However, some PLA Navy observers appear rather unimpressed by American efforts in ASW. The same official Chinese Navy journal observes: “The U.S. Navy actually has not had sufficient exercises in the [ASW arena] and also lacks experience.”79 In the same article, it is likewise noted that “conducting ASW in the littorals represents a special difficulty for the USN” and that “the combat advantage of the U.S. Navy nuclear submarine force in the littoral areas is far from obvious.”80 On this note, Campaign Theory Study Guide, a 2002 textbook written by China National Defense University scholars that draws on a variety of high-quality doctrinal publications, emphasizes that “nuclear powered attack submarines have difficulty operating in close proximity to shore due to natural conditions.”81 Another Chinese naval analysis suggests that “up to 2005, the USN has altogether 350 ASW platforms, just 11% of the number of [ASW] platforms it fielded in 1945. Moreover, many of these current naval and air platforms are not specialized for ASW, but more often are multi-mission platforms.”82 This quantitative comparison across historical periods is crude in some ways, but there is no denying that inherent physical principles combined with the vast geographical area of the Pacific Ocean will likely keep ASW an asset-intensive mission, even in the age of “net-centric warfare.”

The U.S. Navy Submarine Force-Level Trajectory

Chinese discussions of the American submarine force focus heavily on the continuing decline in its size. As one article from a People’s Republic of China (PRC) naval interest publication states, “The decline of U.S. submarine strength is inevitable.”83 Indeed, that a wide variety of Chinese naval sources share this evaluation suggests that this “decline” now passes for conventional wisdom within the PLA Navy. The Chinese naval community is likely paying close attention to internal U.S. debates, knowing that investments made (or forgone) today in submarine fleet modernization shape the future fleet.

Some Chinese assessments of the Seawolf program appear to point out indirectly the internal political tensions that hold down American submarine build rates now and perhaps in the future. One volume notes: “Although the Sea Wolf– class SSN gathers the era’s most advanced technology in a single hull, and possesses beyond-first-class performance, the appraisals of ‘Sea Wolf’ by American public figures from all walks of life differ, with a roughly half-and-half split between praise and condemnation.”84

Taking the long view, Chinese naval strategists recognize that force levels have dropped drastically from Cold War levels. One source observes, “Since 1989, the U.S. Navy’s nuclear-powered attack submarine [force] has been reduced by half.”85 A more recent Chinese naval press article estimates that “[U.S.] nuclear attack submarines will decline in number by close to 40%, eventually reaching 30 boats.”86 This calculation is roughly consistent with a projection in Modern Navy that anticipated a sustained build rate of one boat per year.87 Rear Admiral Yang Yi, writing in 2006 on the future size of the American submarine force, quoted one American analysis as follows: “China already exceeds [U.S. submarine production] five times over. . . . 18 [USN] submarines against 75 or more Chinese navy submarines is obviously not encouraging [from the U.S. perspective].”88

A Reputation for Mastery?

This article demonstrates that Chinese strategists are keenly interested in the U.S. Navy’s submarine force. Thousands of articles have reviewed various aspects of American submarine capabilities, operations, and developmental trends. There is clear evidence that Chinese naval analysts have enormous respect for U.S. submarines, submariners, and their weapons. Certainly, China aspires to be a submarine power and hopes to emulate certain aspects of American experience. However, it is equally clear in these writings that the U.S. submarine force is seen as a key challenge in any military confrontation between Beijing and Washington. It is significant in that regard especially that Chinese analysts are increasingly drawing attention to, and seeking to remedy, their antisubmarine warfare deficiencies. The study also reveals an apparent assumption within Chinese naval analytic circles that American submarine force levels are on a downward trajectory.

The authors are research faculty in the Center for Naval Warfare Studies at the Naval War College in Newport, Rhode Island. They are members (Dr. Goldstein is the founding director) of the College’s China Maritime Studies Institute. The opinions expressed in this report are those of the authors alone and not the assessments of the U.S. Navy or any other entity of the U.S. government.


  1. “美国雷声公司拟用商用流行技术更新潜 艇作战系统” [U.S. Raytheon Corporation Draws Up a Plan to Use COTS to Upgrade Subs’ Systems], 情报指挥控制系统与仿真 技术 [Intelligence, Command, Control, and Simulation Technology], no. 10 (2003), p. 19.
  2. 戴维 [Dai Wei], “ESM 对潜艇支持的新 作用” [ESM’s New Role in Submarine Support], 情报指挥控制系统与仿真技 术 [Intelligence, Command, Control, and Simulation Technology], no. 7 (1999), p. 19. 46. 李平, 陆炳哲 [Li Ping, Lu Bingzhe], “美 国虚拟潜望镜研究及进展” [Research and Progress of the American Virtual Periscope], 船舶电子工程 [Ship Electronic Engineering] 26, no. 5 (2006), p. 199.
  3. This article does not analyze Chinese examinations of U.S. sonar, navigation, combat control, ESM, or radio systems.
  4. 李书甫 [Li Shufu], “水下无人航行器” [UUVs], 舰载武器 [Shipborne Weapons], (April 2003), pp. 57–60.
  5. See, for example, the “US Submarines, Antisubmarine Warfare and All News” section of the China Defense.com Forum at www .china-defense.com/forum/index.php ?showtopic=1541.
  6. 王绪智 [Wang Xuzhi], “潜艇大革命—近岸 作战催生美国下—代多用途核潜艇” [The Submarine Revolution: Littoral Warfare Will Drive the Multirole Nature of America’s Next Generation Nuclear Submarine], 现代舰 船 [Modern Ships] (June 2002), pp. 30–33.
  7. 杨毅, 赵志军 [Yang Yi and Zhao Zhijun], “美国核潜艇艇长是怎样选拔的?” 17 Collins et al.: 85 [How Are American Submarine Commanding Officers Selected?], 当代海军 [Modern Navy] (December 2001), p. 17.
  8. 杜朝平 [Du Zhaoping], “美国为什么不装 备常规潜艇” [Why the U.S. Is Not Equipped with Conventional Submarines], 舰载武器 [Shipborne Weapons] (January 2004), p. 19.
  9. Qi Yaojiu, “Reflecting Again on the San Francisco,” p. 41.
  10. Ibid.
  11. Du Zhaoping, “Why the U.S. Is Not Equipped with Conventional Submarines,” p. 21.
  12. 拜科夫, 济科夫 [Zykov and Baikov—in Russian], 水下间谍战的秘密 [Secrets of Undersea Espionage] (Shanghai: Shanghai Translation, 2006).
  13. Ibid., p. 10.
  14. Ibid., p. 12.
  15. Ibid.
  16. Tai Feng, “Does China Need Antisubmarine Patrol Aircraft?” p. 70.
  17. 管带 [Guan Dai], “走向未来的中国反潜作战” [Looking toward Future PLA Navy Antisubmarine Warfare], 舰载武器 [Shipborne Weapons] (August 2005), p. 33.
  18. 蓝杰斌 [Lan Jiebin], “中国反潜装备的发展” [China’s ASW Equipment Development], 舰载武器[Shipborne Weapons] (February 2004), p. 29.
  19. 巡抚 [Xun Fu], “中国海军反潜武器的发展” [PLA Navy Antisubmarine Weapons Development], 舰载武器 [Shipborne Weapons] (August 2005), p. 29.
  20. Tai Feng, “Does China Need Antisubmarine Patrol Aircraft?” p. 73.
  21. Xun Fu, “PLA Navy Antisubmarine Weapons Development,” p. 30.
  22. Tai Feng, “Does China Need Antisubmarine Patrol Aircraft?” p. 73.
  23. Ibid., p. 75.
  24. Ibid., p. 73.
  25. See, for example, ibid., p. 72; and Xun Fu, “PLA Navy Antisubmarine Weapons Development,” p. 30.
  26. 刘衍中, 李祥 [Liu Yanzhong and Li Xiang], “实施智能攻击的现代水雷” [Carrying Out Intelligent Attacks with Modern Mines], 当 代海军 [Modern Navy] (July 2006), p. 29.
  27. For a much more detailed discussion of this issue, see Andrew Erickson, Lyle Goldstein, and William Murray, “China’s Undersea Sentries: Sea Mines Constitute Lead Element of PLA Navy’s ASW,” Undersea Warfare (Winter 2007), pp. 10–15.
  28. Lin Changcheng, “The Hidden Dragon in the Deep,” p. 30.
  29. Ibid., p. 31. The “first island chain” comprises Japan, its northern and southern archipelagoes, South Korea, Taiwan, the Philippines, and the Greater Sunda Islands. See Xu Qi, “Maritime Geostrategy and the Development of the Chinese Navy in the Early Twenty-first Century,” trans. Andrew S. Erickson and Lyle J. Goldstein, Naval War College Review 59, no. 4 (Autumn 2006), pp. 47–67, esp. note 11.
  30. Xun Fu, “PLA Navy Antisubmarine Weapons Development,” p. 28.
  31. 陈位吴 [Chen Weiwu], “解放军新基洛” [The PLA’s New Kilos], 国际展望 [World Outlook] (July 2006), p. 25.
  32. Xun Fu, “PLA Navy Antisubmarine Weapons Development,” p. 29.
  33. Ibid., p. 32.
  34. 许世勇 [Xu Shiyong], “美海军实施网络反潜 新战略” [The U.S. Navy’s New Network ASW Strategy], 当代海军 [Modern Navy] (September 2006), p. 44.
  35. Ibid. For an equally unimpressed American view, see John R. Benedict, “The Unraveling and Revitalization of U.S. Navy Antisubmarine Warfare,” Naval War College Review 58, no. 2 (Spring 2005), pp. 93–120.
  36. Xu Shiyong, “The U.S. Navy’s New Network ASW Strategy,” p. 44.
  37. 薛兴林 [Bi Xinglin, ed.], 战役理论学习指南 [Campaign Theory Study Guide] (国防大 学出版社 [National Defense University Press], 2002), vol. 3, p. 261.
  38. 石江月[Shi Jiangyue], “‘中国潜艇威胁’与美 军反潜战的复兴” [“The Chinese Submarine Threat” and the Revival of the U.S. Military’s ASW], 现代舰船 [Modern Ships] (May 2007), p. 17.
  39. 胡锦洋 [Hu Jinyang], “外媒: 中国海上‘狼 群’挑战美军潜艇霸权” [Foreign Media: China’s “Wolf Pack” at Sea Challenges American Submarine Hegemony], 海事大 观 [Maritime Spectacle] (July 2006), p. 45.
  40. Wang Yu and Yao Yao, eds., World Naval Submarines, p. 127.
  41. 孟昭珍, 张宁 [Meng Zhaozhen and Zhan Ning], “潜艇承担的新任务” [Submarines Assuming New Missions], 情报指挥控制系统 与仿真技术 [Intelligence, Command, Control, and Simulation Technology] (April 2003), p. 12.
  42. 石江月[Shi Jiangyue], “美国海军需要什么样 的舰队?” [What Kind of Fleet Does the U.S. Navy Require?], Navy Require?], 现代舰船 [Modern Ships], (December 2006), p. 12. 87. 张晓东, 王磊 [Zhang Xiaodong and Wang Lei], “美国海军未来 20 年发展规划” [The 20-Year Development Program of the U.S. Navy], 当代海军 [Modern Navy] (August 2006), p. 51. 88. Yang Yi, “Who Can Estimate the Future Number of Submarines?” p. 28.

Featured Image: Virginia-class submarine Indiana (SSN-789) Departs for Sea Trials, May 2018. (via Navsource)

Chinese Evaluations of the U.S. Navy Submarine Force, Pt. 1

This article originally featured in The Naval War College Review in 2008 and is republished with permission. Read it in its original form here. It will be republished in two parts.

By Gabriel Collins, Andrew Erickson, Lyle Goldstein, and William Murray

The U.S. Navy submarine force has set the standard in undersea warfare for at least half a century. America’s submarines made a vital contribution to victory in the Second World War, and they formed an elite force of truly innovative capabilities during the “Cold War at sea” with the Soviet Navy. Since the end of the Cold War, the submarine force has been a leader among U.S. military warfighting communities in transforming itself to remain relevant against militant Islamist extremism and other emerging threats.

In such missions, the submarine force conducts strategic deterrence, intelligence and surveillance, extended-range land attack, and insertion of special forces, in addition to forming the essential backbone of the Navy’s mission of sea control—the all-important, enabling task of maintaining command of the seas for the U.S. armed forces. With the launch of the first of the Virginia class in 2003, the Navy’s position at the forefront of global submarine forces was set for the foreseeable future.

Perhaps partly inspired by the great successes of the U.S. submarine force, navies around the world have invested heavily in undersea warfare, especially in submarine capabilities. China stands out among these as an emerging submarine power. Over the last decade, Beijing has been building four different classes of boats while importing the Kilo-class diesel submarine from Russia in large numbers. Indeed, China’s intense focus on undersea warfare has led some to speculate that a transpacific rivalry is already under way, at least with respect to submarine capabilities. As policy makers in Washington grapple with the challenge of China’s rise, therefore, it may be wise to consider how Beijing is approaching its evolving naval strategy dilemmas. This article examines Chinese views of the American submarine force. As that submarine force constitutes one of the most vital elements of Washington’s overall strategy for establishing and maintaining sea control in times of conflict, Beijing’s assessment of those capabilities may be critical to uncovering the future evolution of this nascent rivalry.

More specifically, then, this research was undertaken for three reasons:

  • The U.S. Navy submarine force is thought to represent a key capability for conflict scenarios involving China.
  • This part of the U.S. Navy has undertaken major efforts at transformation within a new geostrategic and technological environment.
  • The American submarine force represents a rather well-defined warfare area and thus lends itself to a bounded research effort.

Over the last decade, there has been an explosion of publishing in China on all subjects, including strategic and military-technical research. Thus, there are at least five serious journals devoted to naval warfare and dozens of more technically oriented journals.1 In this project, well over a thousand Chinese articles were surveyed, of which approximately 150 were judged worthy of closer scrutiny and analysis by the research team. The danger of circularity—attributing to Chinese analysts ideas that have simply been translated from original English-language sources into Chinese—is real, but one that the research team carefully considered throughout. Most Chinese journals now openly attribute English-language articles to their original sources. By and large, this kind of material (direct translation from English) was not evaluated in this study, in favor of articles that appeared to represent the actual opinions of Chinese naval and defense analysts.

This article is divided into five parts. The first section surveys Chinese reactions to a variety of current issues in the U.S. submarine force, including recent deployments and incidents of special interest. A second section examines Chinese evaluations of specific submarine force capabilities, focusing especially on new factors (e.g., the development of SSGNs) that have been central to transformation efforts. Section three considers some critical historical issues, particularly Chinese perceptions of U.S. submarine operations during the Cold War. A fourth section considers how Chinese analysts believe their antisubmarine forces would match up against the U.S. submarine force. Section five reviews Chinese perceptions regarding the overall future trajectory of the U.S. submarine force. A conclusion summarizes the article and offers policy recommendations.

Overall, this article finds that Chinese naval analysts study the U.S. submarine force in excruciating detail, as concretely manifested in thousands of both strategic and technical articles that focus on it.2 As one Chinese naval analyst puts it, “Nuclear attack subs are the most worthwhile weapons investments because they are the most survivable weapons platforms. . . . During a regional conflict, [U.S.] nuclear attack submarines are the first in and last out.”3 Nevertheless, there is also a keen appreciation that the U.S. Navy is focusing primarily on ongoing military operations in Iraq and Afghanistan. Writing in the official PLA journal 当代海军 (Modern Navy), one analysis declares, “The U.S. Navy’s capabilities to wage war at sea are gradually declining, and open ocean warfare is already not a focal point.”4 Recognizing the potentially major role of the U.S. submarine force in China contingencies, another analyst suggests: “On the basis of a great quantity of research, the PLA [People’s Liberation Army] believes that U.S. nuclear submarines are very quiet, and difficult to discover and counterattack; at the same time, [their] attack power is great, [and] must [be] restrain[ed].”5 Such assessments underline the importance of a closer examination of Chinese perspectives concerning the American submarine force.

Current Developments

In order to give a sense of what Chinese analysts believe to be the trajectory of U.S. submarine force development, it is useful to examine their assessments of two significant recent events: the grounding of the Los Angeles–class submarine USS San Francisco (SSN 711) and the stationing of nuclear-powered submarines on Guam.

The Grounding of the USS San Francisco

The collision of San Francisco with an underwater mountain on 8 January 2005 greatly interested China’s naval press. The articles published then, which prominently feature official U.S. photos of the damaged vessel, express admiration that a submarine that received such damage could have returned to port. This respect is couched in terms of the fundamental strength designed and built into the ship, however, not in terms of the critical factors of crew training and damage control. Author Qi Yaojiu, for example, wrote approximately four months after the incident in a typical article, “In order to investigate battle damage strength, the U.S. undertook strength tests [for submarines] under the conditions of nuclear weapons detonation.” Additionally, “almost every U.S. submarine, before entering into active service, undergoes tests that use underwater explosives to evaluate resistance to battle damage.”6 Notwithstanding this apparent respect, the author recognized that the damage San Francisco incurred would have amounted to a “mission kill,” stating: “If the San Francisco collision had occurred during wartime, and crew members had experienced such wounds, the San Francisco would essentially lose its basic combat effectiveness.”7 A realization that submarines do not have to be destroyed in order to lose combat effectiveness could influence Chinese operational calculations.

Also characteristic of Chinese discussions of San Francisco’s grounding is an undercurrent of bewilderment, asking in effect, “Why were they going so fast?” The tone of analysis implies that such a high-speed transit is somewhat reckless. Thus, one Chinese analyst states that “a nuclear submarine in the process of underwater high speed transit is confronting serious danger” and that “even some U.S. Navy officials expressed that they could not understand the incident.”8 Another author declares, “It is well known in all navies that as soon as a submarine enters international waters in order to protect its stealth, the submarine will not rely on its active sonar. Objectively speaking, a submarine at high speed that is not operating its active sonar is in danger comparable to a vehicle without headlights traveling in the pitch dark.”9 Perhaps because China’s submarine force consists primarily of diesel submarines that rarely make high-speed, long-distance transits, the circumstances surrounding the collision seem peculiar to Chinese naval analysts.

Chinese analyses of the San Francisco incident recognize the United States as a world leader in submarine rescue.10 As one author observes, “Overall, the USN employs the best submarine rescue vehicles and has the most extensive exercises, so its submarine rescue capability leads the world.”11 This appraisal is corroborated in Modern Navy: “Over the last few years, the U.S. Navy has continuously explored submarine rescue methods, and thus strengthened international cooperation, enhancing submarine rescue exercises with its allies. For us this represents a certain inspiration.” Moreover, the Chinese author states, “small groups at various bases are alternatively ready for war or ready to go out and undertake the rescue of an American or allied submarine at any time.”12 Even though the Chinese Navy evidently has extreme respect for the U.S. submarine force, the analyses of the San Francisco incident appear to show awareness that even this elite force can make errors and must invest in cutting-edge rescue technologies.

SSNs in Apra Harbor

As might be expected, China’s naval press has watched the military buildup on Guam with great interest, particularly that of the American submarines.13 A 2004 article in Modern Navy suggests, “The U.S. Navy has stationed three nuclear powered Los Angeles–class attack submarines on Guam. At present, the U.S. military has considered dispatching an additional 6 nuclear submarines. . . .Deployment of such weapons would give the U.S. military considerable capacity to ‘gain the initiative by striking first’ at us from the sea.”14

The same journal a year later described the basing of nuclear-powered attack submarines (SSNs) on Guam in greater detail, observing that the United States officially reestablished Submarine Squadron 15 on Guam under Submarine Group 7 in February 2001 and deployed three nuclear-powered attack submarines there: the first and second in fall 2002 and the third in summer 2004. Moreover, as administered by Commander, Submarine Force Pacific, the submarine group “on the basis of troop deployment plans regularly dispatches 4–5 submarines under its 7th fleet jurisdiction. The duty period of these submarines is ordinarily 6 months. Each submarine can execute missions independently, or can attach to a carrier battle group.”15

The operational significance of stationing SSNs on Guam is not lost on Chinese naval analysts. One observes that “if [a submarine] sets out from Guam, especially in a Taiwan Strait crisis, it may only require 2 days or so.”16 A significant finding of the present study is that even in official journals, Chinese analysts are exploring Guam’s vulnerabilities. The same author notes that Guam, in addition to conferring some advantages to the United States in a Taiwan crisis, also carries self-defense vulnerabilities having strategic implications:

“The U.S. military has still not established a defense system of anti-aircraft, antimissile, and other defense systems on Guam—[there exists] only a pittance of coastal patrol forces. Once there are hostilities, Guam’s defense can only rely on the U.S. Navy’s sea-based missile defense system and Air Force joint operations. Consequently, in wartime, Guam’s defense is still a problem; also, because it is in a special position surrounded on four sides by ocean at the intersection of three major international sea lanes, it is impossible to defend effectively. If the other side’s long-range ballistic missiles, submarine-launched cruise missiles, long-range bombers or maritime special forces operations units, etc., can break through Guam’s peripheral warning and defense, [to] destroy or seriously damage its naval port, airfield, munitions warehouse, and communications system, [then] the entire operational system of America in the Pacific Theater can become ineffective, its sustained warfare capability can greatly fall short of requirements [and] its resolution and dynamics of military intervention would have to change.”17

Regardless of the validity of their specific claims, then, it is clear that some Chinese analysts perceive Guam to be vulnerable to offensive attacks.

U.S. Navy Capabilities

Having set the scene by reviewing major submarine force developments noted by Chinese analysts, we now turn to a more comprehensive survey of the major American capabilities that have attracted their attention. These include nuclear powered cruise missile–armed submarines (SSGNs) and Tomahawk cruise missiles, Trident submarines, fast attack submarines, sensors and systems, and research and development.

SSGNs and Tomahawks

Chinese analyses demonstrate interest in the Navy’s four new SSGNs, their conversion from Ohio-class ballistic-missile submarines, and their mission areas.18 A fairly typical article observes that:

“refitting focal points are refitting the first 1–2 of 24 ballistic missile launch tubes for the use of special forces; tubes 3–10 into special forces use or for Tomahawk cruise missiles; [and] tubes 11–24 for Tomahawk cruise missiles. After refitting, the submarine can carry 154 Tomahawk cruise missiles, and 66 special forces personnel, a dock/shipyard cover, a frogman transport ship (SDV), and an advanced Seal Transport System (ASDS).”19

Although they clearly recognize the potential value of an SSGN’s embarked special operations forces, Chinese analysts appear to be much more impressed by the implications of one SSGN’s potentially large inventory of Tomahawk cruise missiles and the high readiness rate that SSGNs will be able to maintain. One perceptive article observes that these features will allow other ships to focus on different mission areas:

“After being refitted, SSGNs will be deployed 65% of the time each year on average. . . . As such, the USN will always have at least 2 SSGNs ready for battle at any time, and in wartime, 1 SSGN can take over the duties of many attack submarines and surface ships. Once the SSGN goes into service, this will significantly reduce the land attack burden shouldered by the surface fleet and allow it to focus on providing air defense against missile threats. At the same time, the SSGN will reduce the land attack role of SSNs, enabling them to concentrate on anti-surface and ASW [antisubmarine warfare] missions.”

The same analysis also recognizes with some alarm that “it is conceivable that in the future the arsenal ships could from a safe distance simultaneously rain 500 or more guided missiles upon several points of an enemy’s territory. Using [the SSGN] would be stealthier and faster than an air raid by carrier based aircraft and would also avoid pilot losses.”20

Chinese literature on SSGNs suggests anxiety regarding this capability and what it may mean for Chinese forces. One analysis calculates that SSGNs will allow the United States to engage in saturation attacks: “The ground forces that have relied on the traditional deception against air attack, such as fake targets and positions, will be severely tested under future conditions in which the U.S. armed forces are able to employ saturation attacks by low-cost [cruise missiles].”21 Another analyst, however, points out that Tomahawks are expensive, estimating that Tactical Tomahawks cost anywhere between $5.7 and 8 million dollars a round.22 One Chinese lesson from the Kosovo conflict was that the United States does not possess an infinite inventory of Tomahawk cruise missiles; even in that relatively minor conflict, it adjusted its weapons stocks to cope with apparent resource limitations.23

Trident Submarines

Chinese writings about SSBN capabilities express concern about potential U.S. plans to place conventional warheads on submarine-launched ballistic missiles. One scholar writes that “the new Trident II D5 can achieve a CEP [circular error probable—generally, accuracy] of nine meters. Therefore, as far as point targets are concerned, there already exists the ability to achieve nuclear destruction with a conventional warhead.” This accuracy, he worries, might raise the risk of war overall: “One can see that through lowering one’s own barriers to war, one can more realistically deter the enemy. This undoubtedly reduces war’s actual combat threshold.”24 This may reflect a Chinese concern that Trident conventionalization could give the United States more ability to coerce China in a variety of combat scenarios.

The nuclear deterrence provided by American nuclear-powered ballistic-missile submarines (SSBNs) is well recognized in the majority of Chinese writings, as is the significance of the shifting of five Ohio-class SSBNs (USS Pennsylvania, Kentucky, Nebraska, Louisiana, and Maine) from the Atlantic to Pacific fleets from 2002 to 2005. This transfer occurred as the four oldest Ohio-class SSBNs, which had all been stationed in the Pacific, were temporarily taken out of service for conversion to SSGNs; the two transactions effectively rebalanced the American SSBN force from a Pacific/Atlantic ratio of ten/eight to nine/five.25

Fast Attack Submarines

Chinese observers are intensely interested in and closely follow other modern U.S. nuclear submarines, including the USS Jimmy Carter, Seawolf, and Hawaii. Highly detailed, full-page color photos of Seawolf– and Virginia-class submarines appear in China’s most prominent naval journals. These photos are usually accompanied by articles that imply an advanced state of technology and advanced acoustic quieting. Thus, for example, Seawolf is described as having

“an X type stern, [sic] employ[ing] a non-circulating main pump SbW [sic] pressurized water reactor, rel[ying] on natural circulation [of cooling water], thereby reducing noise; us[ing] an advanced pump jet propulsor, [thereby] reducing noise, us[ing] anechoic tiles on the hull. Anechoic tiles can absorb the enemy’s active sonar survey waves as well as both separate and reduce the submarine’s own noise radiation. Moreover, this ship’s own machinery power equipment also employs [sound isolation] technology. These measures reduce the Seawolf-class’s noise level to 95 decibels, making it the world’s quietest submarine (ocean background noise is 90 decibels, Kilo 636 noise is 105 decibels).”26

Additionally, Chinese authors believe Seawolf possesses “beyond-first-class performance” and is regarded as the most sophisticated and lethal submarine yet to go to sea, despite its “tortuous development history.”27

The Chinese also respect Virginia-class submarines for their advanced technology and quietness. An author in Modern Navy states that “compared with the Sea Wolf–class submarine, the Virginia is slower and carries fewer weapons, but is just as quiet. Its acoustic signature is lower than that of the improved model of Russia’s Akula-class attack submarine and Russia’s fourth-generation attack submarine that will hereafter be in active service.”28 Another analyst, in discussing the Virginia class’s acoustic achievements, reports, “The Virginia-class has been called ‘the world’s quietest submarine,’ with a cruising sound level that is only 1/10 that emitted by a Los Angeles class boat pierside.”29

The techniques used to build Virginia and its sister ships also evoke respect, with one author noting, “The use of modular construction has been a major breakthrough in the construction of the Virginia-class SSN. . . . This construction method is a revolutionary breakthrough compared to the methods used to build the Los Angeles–class.”30 Modular construction is widely perceived as a tremendous advantage, allowing the United States to “promptly design and build new nuclear submarines on the basis of new circumstances and requirements.”31 Plans for Virginia, it is implied, having been generated by computer-aided design tools and relying on modular construction, could be used as the basis of a new SSBN design.32 Chinese authors argue that Virginia’s impressive technology allows it to “scout, reconnoiter, and keep watch from a concealed position using its modern sensors to gather intelligence; analyze it; fix radar positions, missile bases, and command centers; as well as watch and track warship movements.”33 The Virginia class is thus seen as “a completely new attitude emerging on the world military combat arena.”34 Some Chinese analysts believe “the U.S. will keep building Virginia class boats and the final number could exceed 30.”35

Los Angeles–class submarines receive significant attention from Chinese authors. One article on this class notes, “The American Navy believes that: nuclear attack submarines are the most worthwhile weapons investments because they are the most survivable weapons platforms, have the advantage of being stealthy, and have become one of the premier threats at sea.”36 Another author rates their performance as “outstanding,” with the reservation that although they have superior weaponry, they “might not [have proved] an effective counter to new types of Soviet nuclear submarines.” This impending disparity, in turn, is credited with precipitating U.S. follow-on designs.37 Still another observer notes that Los Angeles–class submarines are aging: “By the year 2020, the U.S. military intends to have built 30 nuclear attack submarines. However, by the year 2016, all of the Los Angeles–class submarines will exceed 30 years of service life”; the writer emphasizes the great expense of replacing them with Virginia-class vessels.38

Chinese naval observers regard American torpedo technology highly. Noting an enviable six decades of torpedo experience, one Chinese author observes, “Since World War II and for a relatively long period, U.S. torpedo technology has always been among the best in the world.”39 With specific reference to the Mark 48 heavyweight torpedo, another analyst assesses that “the [Mark 48] torpedo’s outstanding effectiveness in all combat circumstances has been proven and it can be used to attack surface ships, nuclear submarines, and also diesel electric submarines.”40 The same author describes the aggressive U.S. torpedo-testing program: “The USN has already carried out more than 6500 exercises and warshot firings [with the Mark 48], in addition to 20,000 simulations and 9 million mathematical simulations, so that this torpedo reaches a high state of reliability.” Perhaps in reference to the sinking of Russian Oscar-class submarine Kursk, and also as part of an overall effort to improve submarine safety consciousness, this analyst later observes that “the [Mark 48] system has been in active service since 1982 and there have been no safety accidents.”

Not every Chinese analyst would readily agree that the Mark 48 torpedo or its Advanced Capability (ADCAP) variant is especially fearsome. In a 2005 article, a Chinese author flatly stated, “Traditional heavy-weight torpedoes practically have no way to cope with modern diesel submarines in shallow waters.”41 The author notes that “shallow waters constitute a very acoustically complex warfare environment” and that the U.S. Navy has allocated significant resources to developing sonars suitable for littoral combat against diesel submarines.42 Another analyst, however, appreciates the U.S. Navy’s ability to upgrade the weapon: “At the moment, [the Mark 48] torpedo is still being upgraded, so that it can correspond to the challenges associated with shallow water environments and threat—it is expected to be in service with the USN until 2025.”43

The authors are research faculty in the Center for Naval Warfare Studies at the Naval War College in Newport, Rhode Island. They are members (Dr. Goldstein is the founding director) of the College’s China Maritime Studies Institute. The opinions expressed in this report are those of the authors alone and not the assessments of the U.S. Navy or any other entity of the U.S. government.


  1. This article draws extensively on five of the serious PRC professional publications concerned with naval warfare: 当代海军 (Modern Navy), 人民海军 (People’s Navy), 舰船知识(Naval and Merchant Ships), 舰载 武器 (Shipborne Weapons), and 现代舰船 (Modern Ships). Modern Navy is a monthly magazine published by the official PLAN newspaper People’s Navy, which is the daily newspaper published by the Political Department of China’s navy. Modern Navy offers articles that are often concrete and revealing of important capabilities, initiatives, and exercises. See, for example, 徐红明, 刘新民 [Xu Hongming and Liu Xinmin], “‘敌后’布 雷–中国海军某潜艇突破反潜编队训练 目击记” [Lay Mines “In the Enemy’s Rear Area”: An Eyewitness Account of a Certain PLAN Submarine Exercise Involving Breaking Through Antisubmarine Formations], 当代海军 [Modern Navy], no. 4 (2003), p. 38. 舰船知识 (Naval and Merchant Ships), a semitechnical monthly publication of the Chinese Society of Naval Architecture and Marine Engineering, has directly involved a retired PLA Navy rear admiral, Zheng Ming, formerly head of the PLA Navy’s Equipment Department, in its publication activities. See “我刊召开作者, 读者, 编者座谈会” [Our Journal Convenes a Discussion among Writers, Readers and Editors], 舰船知识 [Naval and Merchant Ships] (August 2006), p. 8. An active-duty PLA Navy admiral has contributed to the journal. See 杨毅 [Yang Yi], “谁 的潜艇今后说了算?” [Who Can Estimate the Future Number of Submarines?], 舰 船知识 [Naval and Merchant Ships] (July 2006), p. 28. Shipborne Weapons and Modern Ships are both monthly journals published by the state-owned China Shipbuilding Industry Corporation (CSIC), China’s largest designer, manufacturer, and trader of military and civilian vessels and related engineering and equipment. In addition to these naval-oriented publications, 中国军事 科学 (China Military Science) is published by the PLA’s Academy of Military Sciences.
  2. Because of the difficulty in conclusively identifying the authors of many Chinese writings on naval issues, this article will use a very broad definition of “naval analyst” —namely, one who engages in research and publication concerning naval affairs.
  3. 钱晋 [Qian Jin], “影子 ‘前锋’ 洛杉矶: 我伴 航母走天涯” [The Shadowy Vanguard Los Angeles Class: Escorting Carriers to the Far Corners of the Earth], 舰船知识 [Naval and Merchant Ships] (August 2002), pp. 38–41.
  4. 张建平, 高倚天 [Zhang Jianping and Gao Yitian], “透视美海军 2035 年: 远 景规划” [Perspective on the U.S. Navy in 2035: Prospective Plans], 当代海军 [Modern Navy] (August 2005), p. 37.
  5. 林长盛 [Lin Changcheng], “潜龙在渊: 解放军水雷兵器的现状与发展” [The Hidden Dragon in the Deep: The Present Situation and Development of PLA Mine Weaponry], 国际展望 [World Outlook], no. 9 (May 2005), p. 32.
  6. 齐耀久 [Qi Yaojiu], “‘旧金山’号核潜艇触 礁事故的再思考” [Reflecting Again on the San Francisco Nuclear Submarine Collision Accident], 现代舰船 [Modern Ships] (July 2005), p. 41.
  7. Ibid., p. 42.
  8. Ibid., pp. 41–42.
  9. 止戈 [Zhi Ge], “旧金山’号核潜艇事故分 析” [Analysis of the San Francisco Nuclear Submarine Accident], 舰船知识 [Naval and Merchant Ships] (March 2005), p. 59.
  10. 孙晔飞, 聂其武 [Sun Yefei and Nie Qiwu], “从美核潜艇出事: 瞧潜艇非战时事故规 律” [Looking at Patterns of Nonwar Submarine Accidents, from the Perspective of 15 Collins et al.: Chinese Evaluations of the U.S. Navy Submarine Force Published by U.S. Naval War College Digital Commons, 2018 82 naval war college review collins, erickson, goldstein, & murray 83 the U.S. Nuclear Submarine Incident], 当代 海军 [Modern Navy] (March 2005), p. 20.
  11. 临河 [Lin He], “常备不懈—美国海军潜 艇救生及启示” [Always Prepared: The Inspiration of the U.S. Navy’s Submarine Rescue Cooperation], 现代舰船 [Modern Ships] (May 2004), p. 11.
  12. Ibid., pp. 9–11.
  13. Among the many articles that examine the U.S. military buildup on Guam are台风 [Tai Feng], “中国需要反潜巡逻机马?” [Does China Need Antisubmarine Patrol Aircraft?], 舰载武器 [Shipborne Weapons], no. 3 (March 2005), pp. 70–75; “美国陈兵关岛虎视台海” [U.S. Troops Deployed in Guam Vigorously Watch the Taiwan Strait], 世界新闻报 [World News Report], 15 February 2001; “美核攻击 潜艇欲驻关岛意何为” [Why America Stations Nuclear Attack Submarines in Guam], 信息日报 [NewsDaily], 3 November 2000, p. 22; “美国核潜艇关岛触礁” [U.S. Nuclear Submarine Strikes a Reef near Guam], 环 球时报 [World Times], 20 January 2005; Zhao Xiaozhuo, “The United States Does Not Want to Get Involved in a Crisis in the Taiwan Strait,” Huanqiu Shibao, 3 January 2005, FBIS CPP20050114000176; “核潜艇进 关岛: 美国居心叵测” [Nuclear Submarines Enter Guam: The U.S. Harbors Unfathomable, Evil Intentions], 中国国防报 [China National Defense News], 2 April 2002, p. B04.
  14. 李杰 [Li Jie], “对美系列海上演习之思考” [Reflections on the Series of U.S. Exercises at Sea], 当代海军 [Modern Navy] (September 2004), pp. 20–21.
  15. 赵宇 [Zhao Yu], “全景扫描: 美太平洋第 七舰队战力, 中部” [Scanning the Entire Panorama: The Combat Power of the U.S. Pacific Seventh Fleet (middle part)], 当代海军 [Modern Navy] (February 2005), pp. 53–57.
  16. 韩江波 [Han Jiangbo], “关岛—美军控制 西太平洋作战体系的‘纲’” [Guam: The “Key Link” in the U.S. Military System to Control the Western Pacific], 当代海军 [Modern Navy] (December 2006), p. 33.
  17. Ibid., p. 34.
  18. For the SSGN program and related operational opportunities and issues, see Charles D. Sykora, “SSGN: A Transformation Limited by Legacy Command and Control,” Naval War College Review 59, no. 1 (Winter 2006), pp. 41–62.
  19. 杨修水 [Yang Xiushui], “2010, 世界大洋的新 生代—核潜艇篇” [In 2010, a New Era on the World’s Oceans: Writing on Nuclear Submarines], 当代海军 [Modern Navy], no. 9 (September 2004), pp. 50–55.
  20. 天鹰 [Tian Ying], “SSGN 即将面世的水下武 库舰” [The SSGN Will Soon Be the World’s Premier Underwater Arsenal], 舰载武器 [Shipborne Weapons] (December 2004), p. 67.
  21. 李文盛, 程建良 [Li Wensheng and Cheng Jianliang], “威胁自海上来: 美海军对陆火力 突击能力的发展特点及影响” [Threat from the Sea: Development and Implications of Development Trends in the U.S. Navy’s Surprise Strike Firepower against the Land], 舰载武器 [Shipborne Weapons] (March 2003), p. 20.
  22. “美国海军拟部署战术‘战斧’导弹” [U.S. Navy Intends to Deploy Tactical Tomahawk], 舰载武器 [Shipborne Weapons] (January 2000), p. 36.
  23. See Li Wensheng and Cheng Jianliang, “Threat from the Sea,” p. 17.
  24. Both quotes in this paragraph are from董 露, 郭纲, 李文胜 [Dong Lu, Guo Gang, and Li Wensheng], “析美国战略导弹常规 改装的动因及影响” [Analysis on the Motives and Effects of U.S. Strategic Missiles Armed with Conventional Warheads], 中 国宇航学会 [China Space Institute] (paper distributed but not presented at Tenth PIIC Beijing Seminar on International Security, Program for Science and National Security Studies and Institute of Applied Physics and Computational Mathematics, Xiamen, China, 25–28 September 2006).
  25. See, for example, 朱伟 [Zhu Wei], “美 9 艘战 略核潜艇聚集太平洋” [Nine U.S. Strategic Nuclear-Powered Submarines Assembled in the Pacific Ocean], 当代海军 [Modern Navy] (November 2005), pp. 58–59. In addition to commenting on the significance of the United States transferring SSBNs and SSNs from the Atlantic to the Pacific oceans, this lengthy, wide-ranging article also devotes substantial space to alleged aging problems in the W76 nuclear warhead, criticizes as overly large and unstable the U.S. nuclear stockpile, and decries the negative effects of all this on Asia-Pacific security.
  26. Yang Xiushui, “In 2010, a New Era on the World’s Oceans,” p. 50.
  27. 汪玉, 姚耀中 [Wang Yu and Yao Yao, eds.], 世界海军潜艇 [World Naval Submarines] (Beijing: 国防工业出版社 [National Defense Industry Press], 2006), p. 127.
  28. 河山 [He Shan], “‘弗吉尼亚’号能否成为新 世纪海上霸王?” [Can the Virginia Class Become the New Century’s Oceanic Hegemon?], 当代海军 [Modern Navy] (October 2004), p. 21.
  29. “‘弗吉尼亚’ 潜艇浮出水面” [Launching of the Virginia Class], 现代军事 [Contemporary Military Affairs] (October 2004), p. 23.
  30. Only three Sea Wolf–class submarines were ever built. The Cold War’s end made it impossible to justify construction of additional hulls, because this submarine had been optimized for combating the Soviet Navy. Wang Yu and Yao Yao, eds., World Naval Submarines, p. 129.
  31. Ibid., p. 29.
  32. 陈位昊 [Chen Weihao], “美国海军调整 部署: 美国核潜艇云集太平洋妄图威摄 中国”[The U.S. Navy Adjusts Deployment: U.S. Submarines Converging in the Pacific Vainly Attempt to Deter China], 国际展望 [World Outlook], no. 6 (March 2006), p. 13.
  33. 曹家伟 [Cao Jiawei], “杀向近海—美海军弗 吉尼亚级新型攻击型核潜艇”[Fighting into the Littoral: The U.S. Navy’s Virginia-Class Nuclear Attack Submarine], 环球军事 [Global Military Affairs], no. 18 (2004), pp. 26–29.
  34. Ibid.
  35. He Shan, “Can the Virginia Class Become the New Century’s Oceanic Hegemon?” p. 21.
  36. Qian Jin, “The Shadowy Vanguard Los Angeles Class,” pp. 38–41.
  37. Wang Yu and Yao Yao, eds., World Naval Submarines, p. 121.
  38. 世画 [Shi Hua], “世界未来潜艇发展前瞻” [World Submarine Development Prospects], 海事大观 [Maritime Spectacle] (January 2007), p. 86.
  39. 黄龙华 [Huang Longhua], “潜艇克星: 世界 反潜鱼雷概览” [The Star for Subduing Submarines: A Survey of World ASW Torpedoes], 环球军事 [Global Military Affairs] (August 2006), p. 48.
  40. 崔峰 [Cui Feng], “Mk48 ADCAP: 美国海军主 战重刑鱼雷” [The Mk 48 ADCAP: The U.S. Navy’s Primary Combat Heavyweight Torpedo], 现代舰船 [Modern Ships], no. 4 (2004), p. 31.
  41. 刘伟[Liu Wei], “外军的鱼雷及鱼雷防御技 术” [Foreign Torpedo and Torpedo Defense Technology], 现代军事 [Contemporary Military Affairs] (May 2005), pp. 34–37.
  42. Ibid.
  43. Ibid. This three-page article is accompanied by full-color pictures of Mark 48 ADCAP circuit boards, torpedo body sections, detailed propulsion system schematic diagrams, and tables with performance criteria.

Featured Image: ATLANTIC OCEAN (April 7, 2012) The Virginia-class attack submarine Pre-Commissioning Unit (PCU) Mississippi (SSN 782) conducts alpha trials in the Atlantic Ocean. (U.S. Navy photo courtesy of General Dynamics Electric Boat/Released)