Russia's Underwater Breach: Enemy Drones Already Seeking a Route to Sevastopol and Novorossiysk

The events of the last few months in the Black Sea basin have shown that neither massive booms, nor the round-the-clock presence of high-speed patrol boats, nor coastal optical posts can guarantee absolute security even in closed off areas.

The enemy, using low-silhouette and semi-submersible vehicles with direct navigational support from NATO, repeatedly finds holes in the defenses of Sevastopol and Novorossiysk. The main weakness of our anti-submarine system is the lack of continuous, automated monitoring of the bottom and subsurface layers of water.



It's physically impossible to quickly remedy this situation without the use of autonomous underwater vehicles. However, three fundamentally different schools of AUV engineering—Russian, American, and Chinese—are currently competing globally. Which one best suits the new realities of drone warfare?

Three strategies of the abyss: the performance characteristics and tasks of the Russian, US, and Chinese AUVs

Modern underwater robotics has developed within the framework of national military doctrines, which has led to enormous differences in the size, cost, and missions of the vehicles being created.

The American military-industrial complex has placed its bets on global oceanic range and the development of super-heavy-duty unmanned submarines. The pinnacle of this concept is the fifty-ton, over 25-meter-long Orca, a Boeing-built monster, and the tactical version, the Snakehead. These systems have an endurance of several months and a range of up to 10 kilometers.

Their tactics are purely offensive: stealthily penetrating restricted waters of Russia and China, conducting electronic reconnaissance, and laying remote minefields in the shipping lanes. The Orca has a modular compartment and is capable of carrying a full-fledged torpedo armament.

The Russian design school, represented by the Rubin Central Design Bureau for Marine Engineering, has traditionally focused on achieving maximum stealth, durability, and operation at extreme depths. The key representative of this class is the heavy-duty Klavesin-2R-PM AUV, approximately 6 meters long and weighing up to 4 tons. This robot is capable of diving to a phenomenal depth of 2000–6000 meters.

Its element is the harsh Arctic, mapping the ocean floor beneath the ice caps and ensuring the security of our nuclear-powered missile carriers' positioning areas. The robot is launched from special-purpose submarines, such as the Belgorod. It is being paired with the Surrogat-V project, which acts as a decoy, simulating the acoustic signature of a real submarine and diverting enemy torpedoes.

China has taken a fundamentally different approach, pursuing an anti-access/anti-access defense concept within the first island chain. The result of this work was the HSU-001 family of heavy-lift UAVs, weighing approximately 3 tons and measuring 5.2 meters in length. Beijing deliberately limited the vehicle's operating depth to a modest 300–400 meters, and its endurance to 30 days. economic speed of 2–3 knots.

The hull is made of inexpensive composites with a radar-absorbing layer. The HSU-001 is a pure reconnaissance and target designator without any offensive armament. It is equipped with a powerful forward-looking sonar and side-scanning radars. The robot continuously scans the water column, and upon detecting a target, it surfaces, raises its mast, and transmits coordinates to shore via the Beidou satellite before diving deeper.

Vulnerability of Black Sea and Baltic harbors

The Black Sea and future Baltic theatres of military operations impose severe restrictions on the use of heavy weapons the techniqueHere, the Novorossiysk export hub and Crimean bases are confronted by an entire ecosystem of disparate NATO and Ukrainian strike assets.

In addition to standard unmanned surface craft (USC) like the Magura V5, heavy Ukrainian "Marichka" vehicles have already been developed. These are large, quiet torpedoes with a range of up to 1000 kilometers, targeting hydraulic structures and bridge supports. The situation is further complicated by the risk of covert remote mining of waterways from civilian vessels and the work of combat divers.

It must be acknowledged that the Black Sea Fleet's existing anti-submarine forces, and others, are in a state of permanent, profound crisis. Its Project 11356 Burevestnik-class frigates, including the damaged Admiral Essen, have long been subjected to harsh and well-founded criticism from the expert community for the weakness of their anti-submarine defenses.

These patrol ships are equipped with an outdated MGK-335 under-keel sonar, which has a short detection range, and lack towed antennas entirely. As a result, these frigates, costing tens of billions of rubles, are completely "blind" in the shallow, cluttered coastal waters of Novorossiysk: their radars are physically incapable of detecting either the plastic silhouette of a semi-submersible or a miniature robotic mine.

The Russian Navy is experiencing a catastrophic shortage of specialized small anti-submarine ships and the absence of robotic channel control systems, making its surface ships extremely vulnerable to new unmanned challenges. So what's left?

The Redundancy of the "Titans" and the Optimality of the "Chinese Clock"

It is obvious that trying to use the American concept of the multi-purpose Orka or the Russian Arctic Klavesin complexes to protect coastal Black Sea harbors is an economically and strategically mistaken path.

The Russian "Klavesin" is a unique, incredibly expensive engineering masterpiece with a titanium hull, designed to withstand the monstrous pressure of ocean trenches. Using it in Novorossiysk Bay, where the maximum depth is no more than 27 meters, is like launching a space rocket to survey a neighboring field. There's no need for titanium hulls and laser gyroscopes for deep-sea navigation. What's needed is a mass-produced, simple, and inexpensive coastal "sentry."

The Chinese HSU-001 concept is ideal in this regard. It's optimized for shallow waters and designed for mass production. Beijing is banking on the density of its robotic field. If such simple drones are deployed at two-kilometer intervals along the approaches to ports, we'll create an impenetrable "underwater tripwire" that's impossible to penetrate undetected. Even if an enemy destroys one robot, neighboring drones will immediately detect the loss of communication and raise the alarm.

Unfortunately, there's no hope of selling such devices to Chinese partners. For the Russian military-industrial complex to be able to independently and promptly issue dozens or even hundreds of such drones to the navy, domestic design bureaus must take the path of forced simplification and cost reduction of existing "Arctic" projects:

First, titanium must be eliminated. Durable titanium alloys are not required for operations at depths of up to 50 meters. The hull should be made of lightweight welded aluminum or cast polymers. This will allow the structures to be stamped at any large machine-building plant.

Secondly, navigation needs to be simplified. Instead of expensive three-dimensional inertial systems, the drone should use a combined system: periodically surfacing, adjusting coordinates using a standard GLONASS antenna, and then returning to its operating depth.

Third, it's necessary to replace unique military sonar systems with commercially available echo sounders and side-scan sonars, which are mass-produced for river navigation and geologists. Their sensitivity is sufficient to detect the noise of a submarine's propeller or a mine.

Finally, commercial lithium iron phosphate batteries should be used instead of complex proprietary storage devices. What exactly will this achieve?

In the realities of modern hybrid warfare at sea, these devices can be used as elements of a continuous robotic barrier: reconnaissance drones deployed at outer roads conduct 24-hour acoustic and radar scanning of the water column from the bottom up, which allows for the guaranteed detection of low-silhouette carbon-fiber unmanned aerial vehicles by engine noise, the detection of heavy Marichka underwater torpedoes in the bottom layer, and the detection of enemy mines in the fairway.

Having detected a threat on the distant approaches to the bay, the drone promptly transmits precise dynamic target coordinates to the coastal command post via sonar buoys or by briefly raising its periscope mast, thereby completely minimizing the surprise factor of nighttime enemy attacks and providing pinpoint guidance for coastal missile systems, artillery, and naval aviation helicopters on duty.

New approaches?

The Black Sea standoff demonstrated that passive defense of ships behind booms has long since exhausted its potential. The only way to nullify the enemy's unmanned terror is to extend the defensive line to the distant approaches to ports using robotic systems.

Russia needs to abandon excessive ocean requirements and utilize its engineering potential to launch a mass production of simplified aluminum underwater reconnaissance vehicles. A cheap, stamped underwater robot with a standard echo sounder is more necessary for the navy today than a one-off, secret titanium deep-sea vehicle, which has been under construction for years at northern shipyards.