Tag Archives: seabed

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)

The Nanxun Jiao Crisis and the Dawn of Autonomous Undersea Conflict

Fiction Topic Week

The following story is the next installment of a series on micronaval warfare. Read Part One of Admiral Lacy’s oral history on the emergence of micronaval warfare, “The Battle of Locust Point.”

By David R. Strachan


The following classified interview is being conducted per the joint NHHC/USNI Oral History Project on Autonomous Warfare.

Admiral Jeremy B. Lacy, USN (Ret.)

November 19, 2033

Annapolis, Maryland

Interviewer: Lt. Cmdr. Hailey J. Dowd, USN 

Good morning.

We are joined again today by Admiral Jeremy B. Lacy, widely considered the father of autonomous undersea conflict, or what has come to be known as micronaval warfare. Admiral Lacy spearheaded the Atom-class microsubmarine program, eventually going on to establish Strikepod Group 1 (COMPODGRU 1), and serving as Commander, Strikepod Forces, Atlantic (COMPODLANT). He is currently the Corbin A. McNeill Endowed Chair in Naval Engineering at the U.S. Naval Academy.

This is the second installment of a planned eight-part classified oral history focusing on Admiral Lacy’s distinguished naval career, and his profound impact on modern naval warfare. In Part I, we learned about the genesis of the Atom-class microsubmarine and its operational construct, the Strikepod, and the series of events leading up to the first combat engagement of the micronaval era, the Battle of Locust Point, where a Strikepod of prototype Atoms tracked and engaged several Russian Istina-class microsubmarines prowling the upper Chesapeake Bay during Baltimore Fleet Week, 2016. Today our discussion will focus on the aftermath of Locust Point, the continued development of the Atom-class microsubmarine, as well as the early days of autonomous undersea conflict, including the first major confrontation of the micronaval era, the Nanxun Jiao Crisis.

The period following Locust Point was a time of high tension and uncertainty. With the United States now facing an unprecedented undersea threat to both the homeland and forces abroad, the president, through a series of classified executive orders, mobilized a full range of U.S. defensive capabilities. This included authorizing a broad expansion of the Atom-class microsubmarine program via the Joint Undersea Initiatives Group (known colloquially as FathomWorks), a consortium of leading defense contractors and specialized units of the United States Navy, Coast Guard, and Marine Corps charged with, among other things, developing a coastal undersea network to defend against foreign micronaval threats.

We joined Admiral Lacy again at his home in Annapolis, Maryland.

Let’s begin today with FathomWorks. Paint the picture, if you will, of those early weeks in the wake of Locust Point.

It was all about testing, evaluation, and improvement. The Atom had performed admirably, but for all intents and purposes, it was still a prototype, and there were serious gaps in coms and navigation that needed addressing, as well as kinks with Falken [the Atom’s artificial intelligence]. Our vision for the Atom-class was achievable, but in order to get there we had to enhance Falken dramatically. Strikepods would be operating – and fighting – in a complex, communication-denied environment for extended periods. This demanded a highly advanced form of artificial intelligence, as well as a more evolved approach to human-machine teaming.

We emerged from Locust Point feeling pretty validated, and confident that Strikepods could be more than just another club in the bag, that they promised much more than minehunting or intel gathering. We knew that this was a capable platform in and of itself that could be integrated into the fleet at the operational level.

But there was no time to dream and tinker. Our mandate was clear, and the sense of urgency was unmistakable. The Russians were on the move, and the threat they posed to our security was greater than at any time since the Cold War. Our analysts had taken one on the chin with Locust Point, but they’d been warning for months that Moscow was working on something highly advanced and very closely guarded, but there was no indication that anything was operational, much less poised to invade our inland waters. A lot of folks at the Pentagon laughed it off. But they weren’t laughing now, especially when we took a closer look at Poseidon.

So Locust Point influenced the Navy’s perception of the Poseidon program?

When we first heard of it, it seemed more implausible than Istina. That the Russians had the know-how or the resources to develop an autonomous microsubmarine was difficult enough to believe, but when we started receiving information on a nuclear-tipped autonomous torpedo, we were honestly beginning to wonder if we were the target of a wildly excessive disinformation campaign. Even when we received intelligence that it had been test fired from the Sarov, we just didn’t see it as a viable platform. But the Istina changed all that.

In what way? 

If the Russians were capable of the miniaturization and AI integration – and audacity – we’d experienced with the Istinas, then we had to assume that Poseidon would eventually threaten our shores as well. We needed a viable micronaval defense.

And so the Atlantic Undersea Network was born? 

Yes. The Atom was incredibly flexible by design, and could be configured to fulfill a multitude of roles. We’d been tossing around concepts for mine warfare, including a variant optimized for the seabed, something akin to a mobile, local area SOSUS, with the capability to detect and engage both surface and subsurface targets. The idea, conceptually, was to have Strikepods fanned out across the seabed near certain approaches to the eastern seaboard – Bangor, Boston, New York, the Chesapeake, Norfolk, Kings Bay. These would serve as the ears for either roving hunter-killer Strikepods, or Atoms housed in undersea microsubmarine batteries. In this way, AUDEN would essentially be an integrated minefield.

The signature feature of the seabed-optimized Atom was the Advanced Seabed Warfare module which, in addition to providing a suite of highly advanced communication and sensor technologies, also housed the SEASTAR [Seabed Static Array] – a passive microsonar array that would deploy from the module and extend about 150 feet upward into the water column. With their SEASTARs deployed, the networked seabed Atoms could act as a large array, identifying and classifying targets and passing that information along to the Strikepods – either roving, or turret-based.

AUDEN was clearly prompted by the immediacy of the Russian micronaval threat, but were you also troubled by other adversary programs, such as the Chinese Shāyú-class microsubmarine? 

We were keenly aware of adversary developments, particularly with the PLAN. The intelligence we’d been receiving on the Shāyú was spotty, but given China’s public successes with Haiyi gliders and deep diving vehicles like the Hailong III, as well as their commitment to an Undersea Great Wall, we were fairly confident that not only did the program exist, but that it was in all likelihood operational. And it wasn’t long before our suspicions proved correct.

In the South China Sea? 

About six months after Locust Point, late in the spring of 2017, I got a call from Seventh Fleet inquiring about our progress on the improved Atom, and whether we’d be up for an overseas deployment. At that point we’d pretty much improved the coms issues, and Falken’s training and testing was nearly complete. After checking with the engineers, we thought we were up for the challenge, and on April 1, 2017, half a dozen 5-ship Strikepods were deployed to the Spratlys in what was called Operation Eminent Shadow. Each pod’s initial configuration was one rogue, two remoras, and two relays, and their mission was to carry out general ISR and ASW operations, focusing primarily on the waters off of Subi, Mischief, and Fiery Cross, and to escort both surface ships and submarines performing FONOPS throughout the central Spratlys.

So there was harassment under the sea as well? 

Oh, absolutely. Of course, none of these encounters ever made headlines. It simply wasn’t in anyone’s interest to publicize them, and anyway there was more than enough high-profile harassment happening on the surface to keep the public and media buzzing.

The concerning thing was that Chinese subs were showing up unexpectedly, at times and places that suggested they knew where we were. Their Y-8s were dropping buoys practically right on top of our boats, and destroyers and frigates would show up suddenly to shoo us away. It was reminiscent of what we were experiencing with our boomers right before the Istinas showed up at our front door. Needless to say, COMPSUBPAC’s hackle was up. So the Strikepods were there to help figure out what the hell was going on.

Were they under the control of COMSUBPAC?

Actually, they were under the control of COMPODGRU 1, out of Norfolk, Virginia. There’d been a great deal of debate over this – whether Strikepods were a platform or payload, whether there should be a centralized Strikepod command versus a more decentralized payload approach. But we pointed at the Air Force piloting Reapers and Predators out of the southwest, and said look, there’s no reason why Strikepods can’t be run out of Norfolk, particularly when we’re talking about providing a persistent forward presence like any high-value asset.

So we’d airlift the Atoms to Guam, load them onto waiting Virginias, who’d then deploy them – from the torpedo tubes, initially, until we were able to fully integrate a launch and recovery system with the Virginia Payload Module.  And then we’d get to work, reporting contacts, keeping tabs on the PLAN. We were even able to test the Remora Module in a live environment, tracking a Yuan-class submarine for ten straight days all over the Central Spratlys. It was all going pretty smoothly, with high fives all around. But the Chinese were still showing up unannounced.

What was it like when you finally encountered the Shāyú? 

It was another day of Eminent Shadow, nothing particularly unusual. It’s Caitlyn’s thirteenth birthday, and I’ve got chaperone duty at 1400 for ice-skating and a fondue dinner, so I skip out early, but then at around 1545 I get an “urgent” from the watch: Something’s happened.

When I get back, the place is going bananas, and a watch officer briefs me. One of our Strikepods – Delta – on patrol off Subi had detected three small contacts closing at about fifteen knots. Initially they were classified as biologicals, given their signatures and behavior, and sensing a collision, the rogue ordered evasive action, accelerating and diving, while ordering a relay to break off and come shallow, probably to ensure communications. A second later, one of the contacts breaks formation and heads toward the relay.

So now Falken is faced with something it’s only experienced in the lab. We’d been developing some rudimentary combat tactics and introducing them into the training regimen, running scenarios where Falken would encounter something hostile. But in almost every case it chose to flee rather than fight. There were just too many variables, too much ambiguity for it to go lethal without a human on the loop giving the order.

The first contact reaches the relay and their signals promptly disappear. With the two remaining contacts closing on Delta, Falken orders Flee, and the Atoms scatter. The contacts split up and lock on to the two remoras, and thirty seconds later they also disappear. The rogue scans for additional threats, and finding none, orders relay-2 to head to the surface to phone it in.

Fortunately Falken had ordered all ships to fire their onboard imaging systems, so from the moment Delta went evasive there was running video. Of course 99 percent of it was just black water and bubbles, but there were five screen grabs that were very compelling.

You had a visual? 

It was another one of those moments – like Cape Charles when we first laid eyes on an Istina. I was honestly half expecting to see an eye, some flukes, or a long jaw and teeth. But there it was – a short hull, a propulsor. We knew it then – we’d just encountered the Shāyú-class microsubmarine.

Was there continued harassment by the Shāyús during Eminent Shadow? 

Almost daily, and as such there was a real sense of urgency at FathomWorks to get Falken in a place to adequately defend itself. We were losing Atoms at a rate of nearly five per week. They needed to fight back.

Were there no attempts at communication? No back channel diplomatic overtures by either side? 

It’s important to understand – this was the dawn of autonomous undersea conflict, a time when there were very few environments left for sovereign governments to carry out covert operations without risk of exposure. The Chinese tactics were risky, to be sure, but they believed – correctly – that we had a shared interest in keeping this sort of thing quiet. The undersea community, regardless of nationality, has always been characterized by a cult-like devotion to secrecy, and in the unmanned era, it would be no different. In fact, in some ways there would be an intensification of that silence, if you will, given the willingness to take greater risks with systems that were hidden from public scrutiny, and posed no risk to human life.

But the risk, of course, was that this new type of conflict could spill over into the manned, visible world and precipitate a more serious, potentially bloody crisis. I’m referring, of course, to the Decatur, and the Nanxun Jiao Crisis. 

Yes, of course. Just because the conflict is unseen and unmanned doesn’t insulate it from the overarching strategic reality. It’s woven into that reality, and its effects can indeed break the surface and escalate, as it did at Nanxun Jiao.

Can you tell us about the Decatur incident, and the events leading up to the strike on the Nanxun Jiao installation? 

So, after Subi we could confirm the Shāyú’s existence, and that the Chinese were serious about it as an ASW platform. It was an eye-opener for sure, but beyond that we knew very little – its capabilities, performance characteristics, or Chinese microsubmarine tactics, or doctrine. But then we had a HUMINT breakthrough.


In early 2018, we get a call from the CIA station chief in Manila. Apparently the embassy received something in the mail that might be of great interest to us – a letter with a simple handwritten sketch of what looks like a missile turret, but on closer inspection the missiles are actually small submarines. Below that sketch are a series of random dots that are actually a fairly accurate representation of the Spratlys. One of the dots has a circle drawn around it – the northern reef of the Gaven Reefs, what the Chinese call Nanxun Jiao.

Needless to say, we were intrigued, but what was particularly intriguing was how the sketch bore a striking resemblance to our working concept for AUDEN.  So the CI folks immediately open a file, and we’re left pondering the possibility that the Chinese have deployed a battery of microsubmarines, and that it could be based on a design stolen from a highly classified U.S. Navy program.

What was the response? 

Well, we were alert to the possibility of disinformation, but to what end? To draw us in to Nanxun Jiao? A lesser-militarized island, one that appeared to be used primarily for logistics and resupply?

We weighed the options carefully, and ultimately decided we needed to take a look. Rather than divert resources from Eminent Shadow, we shipped a new 5-ship Strikepod via SH-60 to the nearest destroyer, USS Decatur, and about six hours after delivery, the FONOP is underway, with the Strikepod sweeping the reef. At first it’s pretty routine, nothing unusual, but then at the five minute mark, we get a flash: seabed contact. Falken positions the Strikepod for a closer look, and thirty seconds later, another flash. Shāyús in the water. Six of them. So we order an immediate withdrawal to Decatur, and the Shāyús give chase.

By now the PLAN destroyer Lanzhou has made her appearance, and has closed to around three miles. The Strikepod, with the Shāyús in pursuit, is at flank, but won’t reach Decatur before it can be safely recovered. So we have a decision to make. Since the encounter at Subi, the engineers at FathomWorks had been working nearly nonstop on combat scenarios, and even worked with DARPA to develop a special wargame for Falken to help it anticipate conflict and learn how to fight. But we were still uncomfortable with it making the call. So we dipped a SUMO [Shipboard Undersea Modem] and hoped it would get the message.

What followed was seven minutes of sheer chaos. The Strikepod goes hot, and now it’s a furball. All that training seems to have paid off, and we were looking at a much different outcome than Subi. But what we quickly realize is that the Strikepod isn’t the Shāyús’ objective. Three of them disengage and resume course toward Decatur, and by the time the captain orders the ATT [Anti-Torpedo Torpedo System] to engage, it’s too late, and they slam into Decatur’s hull just aft of the sonar dome. Meanwhile, the remaining Shāyús and the Strikepod fight it out until the end. About a minute later the Lanzhou makes its aggressive pass across Decatur’s bow.

Was there any damage to the Decatur? 

Nothing of any consequence. Some scratched paint. The Shāyús were inert. It was a warning, and a damn stern one at that.

What was the reaction in Norfolk? 

Shock, on a host of levels. We’d just experienced the most aggressive harassment yet. Chinese employment of microsubmarines was unsettling enough, but they were based on the seabed near disputed areas, and were tasked with threatening our manned warships and kinetically engaging our unmanned systems.

But more unsettling still was what the imagery revealed. As CYAN’s letter suggested, the Chinese system was nearly identical to AUDEN. The turret, the network of sensors on the seafloor, complete with SEASTAR-like tentacles.

They’d gotten there first?

AUDEN was still in testing, so it certainly appeared so. Maybe they’d already made a lot of headway, and the stolen design helped push them over the edge. We knew the Chinese were making huge strides in AI and seabed warfare, but this was too much too soon. The signs were clearly there. They’d either hacked us, or they’d had help.

We knew this was coming, though. We knew that microsubmarines were the future of offensive mining operations, and we were well on our way with Strikepods. But we weren’t expecting our adversaries to be quite so far along.

What was the reaction in Washington? 

We’d been patched into the Situation Room from the very beginning, so all the principals were well aware of what we’d found. Needless to say, they shared our concerns, but were also particularly concerned with the strategic implications – that China had moved beyond island building to leveraging the seabed for weapons emplacements. And of course, if it was happening at Nanxun Jiao, surely it was happening at Subi, Mischief, Fiery Cross, and others.

It was a complex situation to say the least, and there were some fairly heated discussions on how to proceed. Many believed we should strike immediately, to send a message that this type of illegal installation would not be tolerated, particularly as it has been used to destroy sovereign U.S. property and threaten a U.S. warship. Others called for expanding Eminent Shadow to include all of the waters off disputed outposts in order to build a diplomatic case and compel the Chinese to dismantle the sites.

And where did you fall on the matter? 

I felt the crisis called for a blended approach, that neither one alone would have done the trick. Even though a show of force risked emboldening the Chinese, we needed to send a strong signal. Diplomacy could come later, but behind closed doors. A Cuban Missile Crisis-style U.N. confrontation would have made for riveting diplomatic theater, but what if the Chinese didn’t blink? We were talking about what they believed was their territorial sea. So they don’t blink – they refuse to dismantle their microsubmarine batteries. What then? U.S. credibility would be on the line, and we would have no choice but to take action – what would be, at that point, very public action. And suddenly we’re at war in the South China Sea.

And ultimately your approach won the day? 

Yes, it did. The president ordered an immediate expansion of Eminent Shadow. We were deploying Atoms by the dozen to the South China Sea, and all told, spent about eight weeks gathering evidence. 

As you might imagine, we encountered quite a bit of resistance. The Chinese were onto us now, and were expecting us to go sniffing around. The PLAN was on high alert, stepping up air and surface activities, and Shāyús were everywhere.

The Atom’s LENR [Low Energy Nuclear Reactor] afforded excellent standoff capability, so we were able to launch all of the sorties from well offshore. The Strikepods would arrive on station, form up, and wait for the go order. They’d fight their way in, and, with any luck, a few Atoms would penetrate far enough to capture some imagery, beam it to the others, and then race to the surface to relay the data. The plan worked about 75 percent of the time, gathering more than enough evidence to satisfy the policymakers. We lost nearly 120 Atoms out of the 150 participating in the expanded Eminent Shadow. Expensive, yes, but they weren’t human casualties. This new form of conflict was evolving right before our eyes.

And what did you find? 

Ultimately we found operational systems off of Subi, Mischief, and Fiery Cross, with partial construction off Hughes, Johnson, and a few others.

So you have the evidence you need to make a compelling case. Now you move on Nanxun Jiao?

Yes, the planning for the Nanxun Jiao strike – or what was now being called Operation Roundhouse – was complete.

Tell us about Operation Roundhouse. 

During the expanded Eminent Shadow, we were also keeping a close eye on Gaven Reefs, with particular focus on any human comings and goings at the Nanxun Jiao undersea installation. The last thing we wanted was casualties, and from what we could tell, the schedule was routine. Every Wednesday at 10am local, a dive tender would head out over the spot and they’d deploy, and we’d listen as they performed routine maintenance, and after about two hours or so they’d surface and head in.

After several weeks of recon, the date was set – a Saturday at 0300 to avoid any possibility of human activity or unwanted attention from satellites or passing aircraft. (The turret was at a depth of fifty meters, so there would surely be a disturbance on the surface.)

The package was sixty Atoms strong, organized into three waves of Strikepods that would make a staggered approach. The Shāyús had a tendency to be all in at the first sign of trouble with almost no reserve, so we hoped the first wave would draw them out, exposing the turret’s flanks and allowing waves two and three to penetrate and carry out the mission.

The package launched at 0215 for the cruise to staging, approximately 10 miles west of Nanxun Jiao. The go order went out at 0245, and then we waited, watching a real-time feed via a surfaced relay trailing approximately 500 yards behind.

At three miles out we hear the Shāyús pinging away, and at two miles they engage the first wave. Resistance is light, which, in hindsight, should have been cause for concern. We only lose about fifteen Atoms during the first wave, and waves two and three meet with almost no resistance at all. Falken had been trained to race toward the target and detonate at the last possible moment, but with such little resistance we were able to perform a static demolition to ensure more thorough destruction.

So we pull back, and we’re watching the split screen with feeds from various perspectives, including the kill vehicles as they continue to close, and as the turret comes into view…

[Admiral Lacy pauses here.]

That’s when you saw them?

I called immediately for confirmation. The pilots switched frantically between feeds, and, yes – quite distinctly. Dive suits. Four of them.

The room erupted, and we immediately fired off a flash to abort. The relay confirmed, but it was already too late, and half a second later the screens went blank. BDA later confirmed that the mission was a success. The turret was completely destroyed, and many of the surrounding network sensors appeared badly damaged or disabled. We searched in vain for three hours, but there was no trace of any divers.

The next day we received the news.

From Chinese state television?

The lead story was an explosion at a CNOOC facility that claimed the lives of four offshore divers. Of course, it wasn’t uncommon for Beijing to cover up accidents of any kind, particularly when they were security related or politically sensitive. But then we received word from CIA, who’d been running CYAN from the beginning. They’d been trying to track him down, to recruit him for more, and in the course of their research they’d determined that the letter had likely come from a member of the Nanxun Jiao dive team, and that one of the four divers reportedly killed in the CNOOC accident – a Mr. Xin Li – was in fact CYAN.

The Chinese had been onto him?

 Perhaps CIA had been careless while poking around and attracted the attention of Chinese counterintelligence, or…

Or they’d been tipped?

 A very real possibility as well.

And they’d known you were coming?

The fact that Mr. Li had been exposed, and that this had likely led to his death – his execution – along with those of three others, was of course problematic enough. But the fact that there were divers down as Roundhouse was underway, and that one of those divers was most likely the individual who led us there in the first place – the implications were unimaginably grave.

Some questioned whether they’d been killed elsewhere, and were never down there at all. But I’m fairly certain they died there that night. The Chinese wanted to send a message to would-be traitors, and especially to us. It was textbook psychological warfare. They wanted us to know we’d pulled the trigger.

What I can tell you is that there were people in the room that day who were never the same again.

I know I wasn’t.

And the aftermath?

Nanxun Jiao was spun as a stalemate, but it was really a Chinese victory. Four casualties and the perils of autonomous undersea conflict were too much for the politicians to stomach, and so, much as Chinese island building had gone unchecked for years, so too would their undersea buildup continue. 

In just three years we were an order of magnitude beyond Locust Point, and the brave new world of autonomous undersea conflict was coming into focus. The underwater realm was more secretive, more complex, and more dangerous than ever before, but one thing in particular was becoming inescapably clear:

Nothing less than total undersea dominance was at stake.

[End Part II]

David R. Strachan is a naval analyst and writer living in Silver Spring, MD. His website, Strikepod Systems, explores the emergence of unmanned undersea warfare via real-time speculative fiction. Contact him at strikepod.systems@gmail.com.

Featured Image: Project 885 Yasen Class Submarine by Isra Tan.

Seabed Warfare Week Concludes on CIMSEC

By Dmitry Filipoff

Last week CIMSEC published a series of articles focusing on the seabed as an emerging domain of maritime conflict and competition. This topic week was launched in partnership with the U.S. Naval War College’s Institute for Future Warfare Studies who drafted the Call for Articles. Authors assessed the legal frameworks related to seabed operations, the operational flexibility that can be exercised through this domain, the challenges of protecting critical seabed infrastructure, and more. Below is a list of articles that featured during the topic week and we thank the authors for their excellent contributions.

Fighting for the Seafloor: From Lawfare to Warfare by LTJG Kyle Cregge

“…the United States will have to determine how it will shape its own law-based national security strategy considering America’s failure to ratify UNCLOS. At the operational  level, seabed UUVs will likely lead to an arms race given all of the discrete tactical opportunities they offer. In an inversion of land warfare, control of the low ground will grant victory on the high seas.”

Forward…from the Seafloor? by David Strachan

“One such operation experiencing a kind of renaissance is mine warfare which, when combined with unmanned technologies and key infrastructure based on the ocean floor, transforms into the more potent strategic tool of seabed warfare. But even the concept of seabed warfare is itself in transition, and is on track to be fully subsumed by the broader paradigm of autonomous undersea warfare.”

Establish a Seabed Command by Joseph LaFave

“A Seabed Command would focus entirely on seabed warfare. It could unite many of the currently disparate functions found within the surface, EOD, aviation, and oceanographic communities. Its purview would include underwater surveying and bathymetric mapping, search and recovery, placing and finding mines, testing and operating unmanned submersibles, and developing future technologies that will place the U.S. on the forefront of future seabed battlegrounds.”

Undersea Cables and the Challenges of Protecting Seabed Lines of Communication by Pete Barker

“Deep below the waters, travelling at millions of miles per hour, flickers of light relay incredible quantities of information across the world, powering the exchange of data that forms the internet. From urgent stock market transactions to endless videos of cats, undersea cables support many aspects of twenty first century life that we take for granted. A moment’s thought is sufficient to appreciate the strategic importance of this fact. As a result, any discussion of future seabed warfare would be incomplete without a consideration of the challenges presented by ensuring the security of this vital infrastructure.”

Dmitry Filipoff is CIMSEC’s Director of Online Content. Contact him at Nextwar@cimsec.org.

Featured Image: Project Baseline’s Nemo submersible shines its lights on U-boat U-576, sunk on July 15, 1942, lying on its starboard side and showing the submarine’s conning tower and the deck gun in the foreground. (Image courtesy of John McCord, UNC Coastal Studies Institute – Battle of the Atlantic expedition.)