EUROPE and WASHINGTON — Shaken by an underwater explosion that ripped through the Nord Stream pipelines in September, European nations are waking up to the task of securing the ocean floors that house the continent’s arteries of wealth.

But protecting the vast network of energy pipelines and communications cables that line the surrounding bodies of water comes down to a familiar question: Who’s in charge?

That’s because the responsibilities for infrastructure that traverses multiple countries, is privately owned and serves vital national interests are anything but clear. Militaries, with their special skills and equipment for underwater operations, are expected to pick up a chunk of the work. But the scope of the assignment and the technologies involved is still coming into focus.

Analysts consider seabed warfare a growing national security discipline with influences from submarine warfare, countermine operations and harbor protection.

“There are two thrusts here,” said Sebastian Bruns, a naval expert at the University of Kiel in northern Germany. For one, there are high-tech, offensive tactics that involve clusters of autonomous weapons quietly lying on the ocean floor until activated, potentially organizing into something like movable mine fields never to be recorded on any maps, he said.

And then there is the field of protecting critical underwater infrastructure, which has a lot to do with understanding, by way of sensors, what is going on around cables and pipelines, he added. Observing hard-to-reach places deep below the surface is challenging enough; being able to do it at the scale required is another.

“An analogy would be the assignment of two cop cars to watch over the entire highway network of the United States,” he said.

Developments are afoot in individual countries and at the European Union level. At the European Defence Agency, for example, officials are awaiting word from Italy in the first quarter of 2023 on a proposal for a dedicated program for critical seabed infrastructure protection. If approved, the effort could join the growing list of so-called PESCO projects — small, multinational government and industry teams whose work serves as a blueprint for solving specific military capability problems.

The agency also is kicking off a series of studies in January to identify capability gaps and find emerging technology in industry that could fill them, said Conor Kirwan, an Irish naval officer detailed to EDA’s office on maritime programs in Brussels.

Also planned is an examination of national governance mechanisms that touch underwater infrastructure protection.

The analyses are expected to culminate in an EDA-sponsored symposium in late April that aims to bring together military and civilian authorities, private companies and academic researchers.

Peeling back the layers of authorities — military, civilian and commercial — may turn out to be the biggest impediment to Europeans acting jointly against threats. “That’s where the complexity around critical seabed infrastructure lies,” Kirwan said in an interview.

France: Drones to the rescue

France has rushed ahead with new investments in the undersea domain ever since it became the first European nation to launch a national security-oriented seabed warfare strategy in February 2022.

Other nations have published seabed strategies before, but in more civilian capacities, such as the U.S. National Oceanic and Atmospheric Association’s strategy for ocean mapping, exploration and characterization. What made France’s release stand out was its military emphasis, especially as Russia and China — considered adversaries by the U.S. and much of Western Europe — are heavily investing in ways to conduct warfare on the seabed, said Steven Horrell, a senior fellow at the Center for European Policy Analysis.

“Russia and China are clearly moving out to utilize the seabed to hold at risk those transoceanic cables and other things on the seabed,” he told Defense News.

Traditionally, the military has focused on anti-submarine warfare in the undersea domain, he added. With the development of underwater unmanned vehicles and mine countermeasure missions, as well as the increasingly critical need to protect transoceanic cables and gas pipelines, that scope has widened.

“Seabed warfare is another evolution,” Horrell said.

France in particular has high stakes to conquer the mostly unexplored domain. The Earth’s seabed takes up about 139 million square miles, with an average depth of about 2.3 miles. According to France’s seabed strategy, of the approximately 450 submarine cables that convey 99% of intercontinental digital data exchanges, 51 cables land in French national territory (including 27 in metropolitan France), and 24 in overseas French territories.

About three-quarters of the seabed is accessible around 3,000 meters, the strategy states, while 97% is accessible at 6,000 meters — nearly 20,000 feet, thus the nation’s ambitions for reaching those depths.

At the time of the strategy’s release, France only had two remotely operated vehicles capable of reaching 1,000 meters: the H1000 Ulisse and the H2000 Diomede. The two crafts were developed by ECA Group, which recently joined forces with navigation and autonomous systems developer iXblue to rebrand as Exail.

But the Armed Forces Ministry soon announced new investments to test existing underwater vehicles capable of probing further depths, with a stated goal of developing one new sovereign autonomous underwater vehicle and one new remotely operated vehicle by 2025.

On Dec. 15, the ministry announced plans to perform sea trials of Exail’s A18D AUV down to 3,000 meters starting in 2023, for a total of €3.5 million (U.S. $3.7 million). During the biennial Euronaval conference outside Paris this past October, the ministry announced a €4 million contract to similarly test the ability of Kongsberg Maritime’s Hugin Superior AUV to operate at depths of 6,000 meters.

The ministry also signed on for a new six-month trial of Exail’s DriX medium-depth AUV to study more optimized means of launching and recovering unmanned systems. That trial is slated to begin in February 2023 aboard the hydrographic vessel Beautemps-Beaupré.

All three AUVs underwent trials with the French military in 2020 and 2021 under the CHOF (capacité hydrographique et océanographique future) program, which aims to replace France’s three hydrographic vessels with newer ships that can more accurately monitor the seabed and underwater activities.

To date, the DGA military procurement office has aimed to define the future architecture of the next-generation vessels; assess what types of autonomous systems would best help France see a twofold increase in surveying capabilities; and increase its coverage of the seabed by 10%.

Another French program, SLAM-F, will see new developments in 2023: The ministry plans to begin ordering new anti-mine robots built by Thales early in the year, which will ultimately replace the Navy’s manned countermine warfare vessels.

While the ministry’s seabed strategy is focused on the military prospects in the domain, industry partners are also targeting civilian customers for their unmanned underwater vehicles.

French companies Marine Tech and Hologarde joined forces to develop the Manta unmanned hybrid vehicle, an all-electric drone envisioned as operating in three versions: as an underwater surface vehicle or subsurface vehicle at about 3 meters deep; as an underwater surface vehicle/autonomous unmanned vehicle at 300 meters deep; and as a platform able to operate down to 6,000 meters deep.

The Manta, a silver vessel resembling its animal namesake, can provide ocean mapping, reconnaissance and underwater interventions. The variant that can operate down to 300 meters will be commercialized in January 2023, said Jean-Luc Pierrisnard, technical manager and co-founder of Marine Tech. The initial target customers are in the oil and gas sectors in the Middle East, Pierrisnard added.

Under their temporary joint venture dubbed Marine Garde, Hologarde — a subsidiary of Aeroports de Paris — and Marine Tech developed the Manta, with 60% financial support from the French Armed Forces Ministry’s Defense Innovation Agency — an office similar to the U.S. Defense Advanced Research Projects Agency.

The project launched in 2019, when both companies were partnering with the agency on separate efforts. The businesses came together as the ministry began to seek new unmanned underwater vehicles for seabed operations, Pierrisnard and Hologarde Managing Director Thierry Lamaire told Defense News on the Euronaval show floor in October.

Pierrisnard said the ultimate goal is to field a model that can work at depths of 6,000 meters, which will require a different motor and a resizing of the electronic units. No date is set for a sea trial, he added.

Companies at Euronaval noted the challenges in not only developing unmanned underwater vehicles capable of descending to such depths, but in testing them. It can be prohibitively expensive for a small business to rent a boat and sail out to waters that are approved for testing and are that deep; thus, co-financing from government partners is critical, noted Lamaire.

Italy: A serenade of signals

The Italian Navy is now actively involved in protecting subsea internet cables in the Mediterranean after signing a cooperation deal in July with Italian telecommunications company Sparkle.

“Joint activity is now underway on the cables we manage,” said Fabrizio Buglio, network and service platforms director at Sparkle, which owns or co-owns 600,000 kilometers (nearly 373,000 miles) of internet cables globally.

The deal envisages the Navy would not only keep an eye on cables in the Mediterranean Sea but also share maps of the seabed and intervene in “emergency” operations.

Rear Adm. Vito Lacerenza, the commander of the Italian submarine fleet, has said the Navy’s new sub types are designed to work with undersea drones, allowing the service to better watch cables.

Buglio said Sparkle already monitored the automatic identification system so it could know which ships were passing over its cables, as accidental damages can never be excluded. Buglio also said the firm was working with university research departments to see if subsea telecommunication cables can act as earthquake sensors.

An Italian Navy source said the service was considering research work into the sensor concept, adding that the service was aware of work undertaken by the the U.K.’s National Physical Laboratory and other partners.

Experts at the lab there believe undersea pressure and vibrations change the way light travels through subsea fiber-optic cables, and those changes can be recorded. The team used a 5,860-kilometer cable between the U.K. and Canada for tests, discovering the spans between signal boosting repeaters could be used as individual sensors.

That suggests the 400-plus subsea cables around the world could be harnessed as a global sensor network, spotting earthquakes and tsunamis.

To be really useful to navies protecting cables, sensor readings would need to register nearby submarines or drones tampering with the cables, but a scientist with the lab, Giuseppe Marra, said that level of sensitivity is not yet in the cards.

“Earthquakes can be registered, but a submarine would be quite challenging, while more research is needed to sense tampering,” he said.

Britain: Mythical multirole kit

Britain is immersed in unmanned underwater technology, partly thanks to offshore oil and gas exploitation in the North Sea.

The country has for years used submarines of various shapes and sizes to deploy and extract special forces on enemy coastlines. And the Royal Navy for several years now has used small, unmanned vehicles, mainly to hunt mines.

Now, technological breakthroughs are enabling all sorts of new unmanned underwater capabilities to be investigated, from anti-access and area-denial to surveillance, reconnaissance, protection of underwater infrastructure and most roles in between.

A recent £15 million (U.S. $18 million) deal between the Navy and MSubs — a small company in Plymouth, England, specializing in underwater tech — will see the service receive a 17-ton, 12-meter-long demonstrator vehicle with a mission range of 1,000 miles.

The aim of the latest contract is to use the Cetus project, named after a mythological sea monster, to develop the Royal Navy’s operational understanding of long-endurance autonomous vehicles; to build trust in autonomous capabilities; to explore potential mission roles; and to inform how the vehicles fit into the underwater battlespace and the service’s future vision.

Delivery of the Cetus platform is scheduled within two years.

Announcing the deal early in November, the Royal Navy said part of the exploration activities would involve the potential for the vehicles to operate alongside conventional submarines, including the service’s Astute-class nuclear-powered hunter-killer boats.

In addition to Cetus and ocean-surveillance ships, Britain is investing in capabilities to support an infrastructure protection program. The Defence Ministry revealed recently it intends to spend £20 million to acquire a remotely operated deep-water salvage vehicle with the ability to manipulate objects and produce high-resolution imagery down to a depth of 6,000 meters.

Independent defense analyst John Louth said the ministry would like to field a fleet of vehicles with the adaptability to undertake a range of missions from similar platforms, among other goals.

“Part of the thinking in governments, particularly the U.S. and U.K., is that you don’t necessarily need different craft to undertake a whole range of missions,” he said. “If you are looking at underwater cables and the deep Atlantic, that’s different to special forces and the littoral environment. But the investment might be better if pooled so their assets can do all those sort[s] of things. The emerging requirement is for something that can do a range of missions.”

The analyst said flexibility extends to the types of platforms from which the autonomous vehicle can operate. One platform option for Cetus, and later vessels, is the multirole ocean-surveillance ships the Royal Navy is hurriedly building to meet a fast-emerging need to further protect critical national infrastructure.

The ministry is initially purchasing a commercial off-the-shelf platform for its seabed warfare program, with an operational date set for 2023. The second ship in the program is currently in the concept phase, with no final decisions taken yet regarding the procurement process.

Germany: Data-driven designs

As EU officials ponder their next moves in securing seabed-borne cables and pipelines, it’s becoming clear that collecting and connecting whatever data exists on undersea goings-on will be a key first step.

Luckily, they need not start from scratch. Private companies emplacing and operating the connections tend to have already installed the technical means to collect information on the condition of their hardware, said Kirwan, the European Defence Agency official.

“The number of sensors that have been developed even to date are generating huge quantities of data,” he said. That explains his agency’s appetite for novel information-processing techniques that can translate signals picked up by sensors into actionable intelligence.

German Navy chief Vice Adm. Jan Christian Kaack has made a similar case for keeping tabs on infrastructure in the country’s territorial waters of the North and Baltic seas. His idea is to integrate sensor data generated by operators, oceanic research institutions, police and the Navy into one operational picture that covers activity above and below water, a sea service spokesman told Defense News.

“Keeping such a picture current would help detect anomalies quickly and enable follow-up,” the spokesman added.

Germany has pledged to support Denmark, Norway and Sweden in protecting their critical maritime infrastructure. The Navy has turned its ships’ travel routes to and from northern naval exercises into patrols to that effect, and officials have sent P-3C Orion maritime surveillance aircraft to watch over objects off the Norwegian cost, according to the spokesman.

Reporting by Vivienne Machi in Stuttgart, Germany; Tom Kington in Rome; Andrew Chuter in London; and Sebastian Sprenger in Washington.

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