Matching the right sensor to the right autonomous platform — for the right mission.
The Strategic Pings ))) newsletter — sonar, autonomous platforms, and undersea strategy by Thomas Meurling.
[Cover: video]
This is a video that complements the article I wrote Yesterday. Here
is the link to my article:
https://www.linkedin.com/pulse/strategic-ping-china-just-deploying-uuvs-mapping-silence-meurling-o2slc
Originally published in the Strategic Pings ))) newsletter on LinkedIn on 2026-04-15. Subscribe there to get new editions first.
The recent recovery of a Chinese UUV in the Lombok Strait should not be treated as a strange maritime footnote. It should be treated as a warning.
Because this was never just about one unmanned vehicle drifting into the wrong place. It was about what that vehicle was likely doing before it was found. And that matters a great deal.
For those of us who have spent years working with sonar, seabed mapping, underwater surveillance, and the brutal realities of acoustic performance, the signal is obvious. China is not only investing in undersea platforms. It is investing in understanding the water itself. That is a much bigger strategic issue.
The undersea battlespace is changing. Quiet platforms still matter. Stealth still matters. But stealth is no longer just about hull design, propulsion, or signature reduction. It is increasingly about who knows the environment best.
And in chokepoints like Lombok, the environment is the weapon.
The Lombok Strait is not just another narrow passage in Southeast Asia. It is one of the few deep-water routes through the Indonesian archipelago that can support submarine transit at meaningful operational depth. That alone makes it strategically interesting. Unlike shallower alternatives, Lombok offers a valuable acoustic corridor for movement between the Pacific and Indian Oceans. If you want to understand where submarines can move quietly, where they may hide, and where their acoustic advantage may begin to weaken, this is exactly the kind of place you study.
Relentlessly.
That is why the technical payload matters more than the paint job or the logo on the hull.
A UUV operating in such an area is not just collecting data. It is building a model of the battlespace. With the right sensor package, it can measure currents, water column structure, seabed topography, ambient noise, and acoustic variability over time. In plain language, it can help answer the questions every submarine commander and every ASW planner cares about.
Where does sound bend?
Where does it die?
Where does the sound travel well?
Where can a submarine disappear?
And where can a submarine be found?
An Acoustic Doppler Current Profiler does not just measure current speed. It helps define the movement of the water itself, including layering and flow conditions that affect station-keeping, sensor performance, and long-endurance loitering. Temperature and salinity sensors do not just produce oceanographic charts. They define thermoclines, haloclines, sonic layer depth, and transmission loss behavior. That means they help predict where sonar performs well and where it does not. Side-scan sonar is not just for pretty seabed pictures. It helps characterize bottom type, terrain complexity, and bathymetric features that may support covert movement or influence acoustic clutter. Ambient noise monitoring helps separate biological, hydrodynamic, and commercial noise from actual targets, which is essential if you want to refine detection thresholds and improve acoustic libraries.
This is where the discussion often gets too polite.
We still hear people describe these kinds of deployments as scientific, exploratory, or dual-use. That is technically true in the same way that a rangefinder can be used for golf or gunnery. Context matters. Intent matters. Pattern matters.
And the pattern is clear.
China is steadily building the foundations for a more transparent undersea battlespace. Not transparent for everyone. Transparent for them.
That is the strategic point. If you can characterize the acoustic properties of key chokepoints, deep-water approaches, and naval transit corridors, you begin to reduce uncertainty. If you reduce uncertainty, you reduce the value of your adversary’s stealth. If you reduce the value of stealth, you begin to shift the balance of undersea deterrence.
That is not a research project. That is preparation.
The Lombok recovery also matters because it fits into a broader trend. This is not about a single vehicle, a single transit route, or a single regional incident. It is part of a larger push toward distributed, persistent, autonomous undersea sensing. The goal is not simply to place more hardware in the water. The goal is to create a better acoustic picture over wider areas, over longer periods, with less human presence and lower political visibility.
That last point is important.
Archipelagic states and maritime democracies face a difficult challenge here. Surface intrusions are visible. Airspace incursions are visible. Even fishing militia can be photographed and named. But undersea data collection sits in a murkier zone. It is often non-kinetic. Often deniable. Often wrapped in the language of marine science or civilian research. That makes it attractive. It also makes it dangerous.
Because by the time the real purpose is fully understood, the data has already been collected.
So what should serious maritime nations do?
First, stop treating Undersea Domain Awareness as an optional luxury. It is becoming a baseline requirement.
Second, invest in fixed and distributed acoustic monitoring across critical corridors, ports, and seabed infrastructure zones. Not as Cold War nostalgia, but as modern layered sensing architecture.
Third, expand the use of multi-static and bi-static sonar concepts for detecting low-observable unmanned systems that do not behave like traditional submarines and do not present a convenient surface signature.
Fourth, establish disciplined recovery, exploitation, and technical intelligence procedures for foreign unmanned systems. Every recovered vehicle is not just an incident. It is a floating database.
And finally, accept a hard truth. If your competitor is persistently mapping the acoustic environment in peacetime, they are not preparing for scientific dialogue. They are preparing for positional advantage.
The undersea domain used to favor the side that could hide best.
Now it increasingly favors the side that has measured the water first.
That is why the Lombok Strait matters.
China is not just deploying UUVs.
It is mapping the silence.
Please comment so we can learn from each other.
Originally published in the Strategic Pings ))) newsletter on LinkedIn on 2026-04-14. Subscribe there to get new editions first.
Critical Underwater Infrastructure (CUI), subsea pipelines, power cables, and global communications links form the invisible foundation of modern society. These assets that carry energy, data, and provide economic stability across oceans are quietly enabling everything from national defense to daily digital life, whilst also becoming increasingly vulnerable.
The sabotage of the Nord Stream pipelines in 2022 and the damage to the Baltic pipeline in 2023 did more than disrupt energy flows. These incidents revealed that much of the critical seabed infrastructure remains unprotected, insufficiently monitored, and difficult to defend via traditional maritime surveillance.
What makes the challenge even more complex is the nature of the threat. Many hostile actions targeting CUI fall into the “grey zone”. Though deliberate and deniable, they’re intended to avert escalation whilst still achieving strategic effects. Attribution is difficult, deterrence even harder, and episodic monitoring is no longer enough. Protecting CUI now requires persistent, high-resolution, and cost-effective underwater surveillance on a continuous basis.
Established approaches to subsea monitoring struggle to meet this requirement. Fixed seabed systems, such as hydrophone arrays, provide persistent monitoring but only at known locations. Once identified, they can be avoided, spoofed, or neutralised. Their static nature is both an advantage and a limitation.
Crewed vessels deliver mobility, but at a prohibitive cost. Daily operating expenses routinely exceed tens or hundreds of thousands of dollars. Their acoustic and visual signatures are unmistakable, making discreet monitoring impossible. Most critically, launching and recovering underwater systems in real sea states exposes crews and equipment to considerable risk.
Standalone AUV operations solve some problems, but cause another: endurance. Battery limitations typically restrict missions to less than 24 hours. When depleted, the AUV must be recovered, recharged, and redeployed. The result is a stop-start surveillance model, punctuated by gaps precisely when persistence matters most.
In short, today’s tools were never designed for continuous, wide-area CUI protection.
A new operational model is emerging that fundamentally changes how subsea infrastructure can be protected.
At its core is a symbiotic USV–AUV concept: Unmanned Surface Vehicles acting as autonomous motherships, supporting and sustaining fleets of Autonomous Underwater Vehicles.
This does not concern replacing ships with drones. It is about breaking the endurance barrier and creating a system where at least one AUV is always in the water – surveying, mapping, and monitoring critical infrastructure – while others recharge, upload data, or stand by. Persistence becomes the standard, not the exception.
The model is simple yet operationally effective. A USV deploys a fully charged AUV to survey a defined CUI corridor. As that AUV approaches its battery or mission limit, it autonomously returns to the USV. A launch-and-recovery system (LARS) enables safe, automated docking, often without the AUV even leaving the water. While the returning vehicle recharges and offloads data, a second AUV is deployed immediately.
The result is a continuous rotation cycle: 1 – one AUV surveying; 2 – one AUV charging; 3 – one AUV processing or standing by. There are no surveillance gaps, no need for crewed recovery, and no dependence on weather windows to dictate operational tempo. This capability establishes the USV as an effective force-multiplying mothership.
The most critical function of the USV in this architecture is launch and recovery, rather than navigation or endurance. A multi-AUV LARS transforms the USV from a basic platform into an autonomous subsea operations hub. It enables safe handling of multiple AUVs in real sea states; in-water docking for charging and data transfer; and elimination of deck-based recovery, the riskiest phase of any subsea mission.
Removing personnel from launch and recovery operations significantly increases safety. Meanwhile keeping AUVs submerged during servicing further increases operational uptime. In this case persistence is no longer limited by weather, daylight, or crew availability.
In this model, the AUV serves as the primary sensor platform, operating directly where CUI is located. Medium-class AUVs offer an optimal balance of payload capacity, endurance, and autonomy for monitoring infrastructure. Equipped with high-resolution sonar, such as Synthetic Aperture Sonar (SAS), they deliver centimeter-scale imagery across wide areas of the seabed. This level of resolution is essential, not optional.
It enables detection of subtle seabed disturbances, newly introduced objects, cable exposure, or burial changes, and provides evidence of tampering or pre-positioned devices. Importantly, it also enables repeatable and comparable surveys, supporting accurate pattern-of-life analysis along critical routes.
Persistence alone is insufficient; data must be transferred securely and efficiently. In the USV–AUV model, data flows seamlessly: 1 – raw sonar data is collected by the AUV; 2 – data is transferred during docking to the USV; 3 – data is then pre-processed onboard to flag anomalies and reduce bandwidth; 4 – pre-processed data is transmitted via encrypted satellite links to shore-based command centres.
The USV acts as a mobile data gateway, providing near-real-time intelligence to national or alliance-level command systems. Once integrated into a wider Maritime Domain Awareness framework, this continuous data stream enables a shift from reactive response to proactive infrastructure defense.
The benefits of this symbiotic model are transformational, not incremental.
Persistence at Scale: Weeks or months of uninterrupted monitoring replace short, disconnected missions; Reduced Risk: No crews are exposed to hazardous launch and recovery operations; Operational Discretion: Low-profile USVs and submerged AUVs significantly reduce detectability; Economic Viability: Replacing crewed support vessels with autonomous motherships makes persistent surveillance financially viable; Scalability: Multiple USV–AUV teams can be deployed simultaneously throughout vast infrastructure networks.
Together, these advantages make unmanned systems a significant force multiplier for CUI protection.
The protection of Critical Underwater Infrastructure is no longer a niche technical problem, it’s a strategic requirement. The USV–AUV mothership model offers a forward-looking doctrine – one designed for endurance, ambiguity, and scale. By making sure that there is always an AUV in the water, it delivers the persistence required to deter, detect, and document hostile activity in the subsea domain.
While this model is highly relevant for CUI, its implications reach further to mine countermeasures, ISR, and long-term seabed monitoring. At a time when underwater infrastructure has become both a target and a strategic lever, adopting persistent, unmanned, and integrated surveillance architectures is no longer optional. It’s the new baseline for maritime security.
Please comment so we all can learn from each other.
Originally published in the Strategic Pings ))) newsletter on LinkedIn on 2026-04-07. Subscribe there to get new editions first.
[Cover: video — Made by Thomas using AI]
Yesterday I submitted my latest Strategic Ping Newsletter – Evolution
of Sea Floor Mapping.
Here is a movie I made using various AI tools, illustrating the
evolution from lead line to modern MBES.
LINK:
https://www.linkedin.com/posts/thomasmeurling_strategicping-hydrography-multibeam-activity-7444783565403492353-uQC4?utm_source=share&utm_medium=member_desktop&rcm=ACoAAAC91OQBPgogARmVAy5SK1cl5Uvy2ygxAHI
Originally published in the Strategic Pings ))) newsletter on LinkedIn on 2026-04-01. Subscribe there to get new editions first.
Hydrography has always been about one thing. Reducing uncertainty before uncertainty becomes expensive.
The Egyptians understood that. Long before sonar, they were already measuring water levels and restoring order after the Nile floods wiped out boundaries and infrastructure. Their tools were simple, but the principle was powerful. Measure carefully. Repeat consistently. Turn water from chaos into something you can manage.
That, in essence, is still hydrography.
[Video: Evolution of Hydrographic]
For centuries, the lead line was the main tool of the trade. A weighted rope lowered to the bottom. One depth point. One moment in time. If you were lucky, a little tallow on the lead would also bring up mud or sand, giving you a clue about bottom type. It worked. Sort of. But it was painfully slow, highly manual, and left enormous gaps between soundings. In other words, it gave you information directly under the vessel and a healthy amount of optimism everywhere else.
Then came the fathometer.
In the 1920s, echo sounding changed the game by allowing surveyors to measure depth acoustically while underway. This was a major step forward. No more dropping a line over the side every few minutes. Now we could collect a continuous depth profile along track. Productivity jumped. Confidence improved. But there was still a problem. A single-beam echo sounder only looks straight down. It tells you what is below the keel, not what is waiting a few meters off to port. Or starboard. Or directly in the gap between survey lines where nasty surprises like to hide.
That is why multibeam mattered so much.
Multibeam did not just improve hydrography. It changed the question. We stopped asking, “What is the depth under me?” and started asking, “What does the entire seabed look like across my swath?” That is a very different level of ambition. And it is the reason hydrography moved from sparse measurement to true seafloor mapping.
One of the important commercial milestones in that transition was the SeaBat 9001. It helped bring multibeam out of the realm of specialist systems and into practical survey operations. Compact. Commercial. Usable. It made it possible for more operators to move from isolated soundings to real swath bathymetry. That was a big deal. Once people saw proper coverage, going back to sparse data felt a bit like going from radar to binoculars and calling it progress.
Then came the systems I know personally.
I had the privilege of helping to lead the development of the SeaBat 8125 and, later, the 7125 as R&D Manager for RESON Inc. The SeaBat 8125 was based on Jens Steenstrup’s (co-founder of RESON) brilliant ideas, with Mark and Kirk as lead engineers. This was a major leap in shallow-water hydrography. It delivered extremely high resolution, using focused beamforming, and helped redefine what surveyors expected from multibeam performance in ports, harbors, and coastal approaches. It was not just about measuring depth better. It was about seeing the seabed with a level of clarity that changed operational standards.
The 7125 took that further. Dual-frequency capability. Greater flexibility. Better coverage. More productivity. Better data in more conditions. This is where multibeam matured from a clever sonar into a true survey system. When operators can reduce infill lines, maintain data quality, and get cleaner results faster, that is not a small engineering improvement. That is commercial and operational leverage.
And then we arrive at the SeaBat T20 & T50.
The T20 & T50 represent the next stage in the evolution. Frequency agility. Advanced beamforming and better sidelobe suppression, resulting in cleaner bathymetry.
Better integration with inertial navigation. Higher data density. Less time fighting artifacts in post-processing. In simple terms, it reflects where hydrography has been heading all along. Not just toward more data, but toward better data. Data you can trust. Data that shortens the path from acquisition to decision.
That is really the story here.
The evolution of hydrographic survey is not just a story of better sensors. It is the story of reducing ambiguity. From Egyptian measurement staffs to lead lines. From lead lines to fathometers. From fathometers to multibeam. From multibeam to agile, high-resolution systems like the SeaBat T50/T51.
I give the examples of SeaBat sonar family, as that is what I’m most familiar with. Similar MBES to T50/T51 would be Norbit Winghead or Kongsberg EM 2042, all excellent MBES systems
We no longer just sample the seabed. We model it. We interpret it. We operationalize it.
And that is a very good thing.
Because the ocean has always been unforgiving to people who confuse limited data with real understanding.
Please comment and provide insight so we all can learn from each other. Did you ever used any of the older SeaBat MBES systems?
Originally published in the Strategic Pings ))) newsletter on LinkedIn on 2026-03-31. Subscribe there to get new editions first.
Naval mines present a uniquely disruptive threat.
Modern warships cost billions, and tankers carry valuable cargo. Global energy markets rely on predictable sea lanes. Yet a relatively cheap mine ($1500), deployed by a fishing boat or patrol craft, can disrupt strategy, spike insurance, halt traffic, and unsettle both military leaders and markets.
That is the genius of the mine. It does not need to sink a fleet. It only needs to create doubt.
And in a chokepoint like the Strait of Hormuz, doubt is operationally contagious.
This is where geography stops being background and becomes a weapon. On paper, the Strait looks wide enough. In reality, commercial traffic is funneled into narrow traffic lanes, which means a small number of mines can create disproportionate disruption. This is not just a naval problem. It is a global trade problem with a sonar solution attached to it.
The mine threat in a chokepoint is not one thing. That is where many simplified conversations go wrong.
You are not dealing with a single neat category of weapon. You are dealing with a layered threat set. Classic contact mines remain dangerous because they are cheap, simple, and psychologically effective. Bottom influence mines are more sophisticated and far more selective, using magnetic, acoustic, and pressure signatures to wait for the right target. Then you have rising mines, which turn the seabed into an ambush position and compress reaction time to almost nothing.
This matters because each mine type creates a different tactical problem. One threatens the hull. Another threatens confidence. The third threatens timelines.
And the environment helps the defender. Variable bathymetry, cluttered seafloor, internal wave activity, coastal traffic, and shallow-to-moderate littoral conditions create exactly the kind of messy operating picture that mine warfare loves. Mines do not need perfect hiding places. They only need enough ambiguity to slow you down.
That is the real weapon here. Delay.
A minefield in a chokepoint functions not only as an obstacle but as a negotiation tool backed by explosives.
Mine countermeasures once relied heavily on courageous personnel performing hazardous tasks in dangerous environments. This approach deserves respect but not nostalgia.
The modern answer is layered, robotic, persistent, and frankly far less sentimental.
First, you need domain awareness before the mines go in. Persistent surveillance matters because clandestine minelaying often hides inside normal maritime traffic. Pattern-of-life analysis, long-endurance unmanned systems, and AI-assisted anomaly detection are no longer nice extras. They are the front line of prevention. If you can identify the craft, route, timing, and behavior associated with mine deployment, you are not just clearing mines. You are shutting the faucet before the floor floods.
Second, once the threat is in the water, you need a detect-to-engage chain that keeps sailors outside the live minefield. This is where unmanned surface and airborne systems earn their keep. Airborne laser systems can search the water column quickly for moored threats. Unmanned sweep systems can trigger influence mines by pretending to be the kind of ship the mine wants to kill. Expendable neutralizers can then prosecute confirmed targets without asking a diver to become the last part of the kill chain.
That is the strategic shift. Not just finding mines, but industrializing the process of dealing with them.
Because in real mine warfare, speed matters, but confidence matters more. One missed mine can reopen the crisis.
If you are serious about modern minehunting, you cannot talk only about platforms. You have to talk about payloads. And specifically, you have to talk about the AN/AQS-20C.
This is not just another towfish. It is one of the more serious answers to the mine problem because it combines multiple sensing modes into one operational package. Towed by the Common Unmanned Surface Vehicle, the AQS-20C brings side-looking synthetic aperture sonar, forward-looking sonar, a gap-filler capability for the nadir zone, and an electro-optical laser imaging function for shallow and near-surface identification.
That matters for a simple reason. Mines are opportunists, and blind spots are invitations.
Traditional minehunting involves tradeoffs: range versus detail, imagery versus speed, coverage versus gaps beneath sensors. The AQS-20C addresses these by combining multiple detection and classification functions in a single pass. In mine warfare, this enhances survival, tempo, and clearance probability.
Combined with the CUSV, this system provides critical standoff capability. The vehicle operates in shallow littoral waters, tows substantial payloads, and maintains endurance. This shifts risk by advancing sensors and platforms while keeping sailors at a safer distance.
That is how it should be.
Mine warfare is among the least glamorous naval operations. Clearing shipping lanes slowly and methodically lacks heroism but is strategically critical. Without reopening sea lanes, discussions of sea control become hollow.
The mine threat is not impressive because it is advanced. It is impressive because it is efficient.
That is why the answer cannot be a single ship, a single sonar, or a single brilliant operator. It has to be a layered architecture of surveillance, unmanned systems, advanced sensing, deception, and precise neutralization. The side that wins mine warfare is usually the side that understands two things first: chokepoints amplify fear, and fear travels faster than any fleet.
Sea mines are cheap. Strategic paralysis is not.
And that is exactly why systems like the CUSV and the AQS-20C matter so much. They do not just find mines. They help restore freedom of movement, which in maritime terms is another way of saying they help restore leverage.
Because in the end, the mission is not to admire the threat.
It is to make it irrelevant.
Please share your comments and insights so we can all learn from one another.
Originally published in the Strategic Pings ))) newsletter on LinkedIn on 2026-03-24. Subscribe there to get new editions first.