UUV Protection: Meet the Autonomous Monsters of the Deep

The combination of prolonged autonomous operation with independent decision-making positions Unmanned Underwater Vehicles (UUVs) as the next phase in the evolution of naval warfare

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The folklore tales of Nessie, the monster of Loch Ness in Scotland, have troubled local sailors for centuries, despite the fact that the actual presence of the monster was never proven empirically. This story illustrates the concerns of sailors regarding things that lurk beneath the surface. Over the years, humans had learnt how to exploit those concerns and developed submarines, which enabled them to take advantage of the fear of the underwater medium to create an element of surprise and deterrence. So, since the First World War, submarines have replaced the Monster of Loch Ness in military strategy by capitalizing on their stealthy, quiet operation, on the fact that they are invisible and on their ability to remain under water for long periods of time and carry missiles.

"The Power Ruling the Seas"

The essential difference between Nessie, the Monster of Loch Ness, and a manned submarine has to do with the fact that Nessie remains under water permanently. It never has to surface for air, for repairs, for replenishing its food supplies and so forth – things that a "human" submarine must do. This ability gap is bridged by the Unmanned Underwater Vehicles (UUVs), which have evolved into the new and autonomous monsters of the deep.

Admittedly, this is only the beginning of a revolution in naval warfare strategy, but anyone possessing a vivid imagination will be able to draw scenarios where UUVs generate their own energy, are made from self-repairing materials and know how to operate in a swarm (or school) to achieve command of the sea. The combination of prolonged autonomous operation with independent decision-making positions UUVs as the next phase in the evolution of naval warfare. The only advantage of manned submarine remains primarily their ability to launch heavy missiles.

Alfred Thayer Mahan, a Rear Admiral in the US Navy, depicted the importance of naval superiority – command of the sea – more than a hundred years ago. In his book The Influence of Sea Power upon History (1890), Mahan outlined the advantages of naval superiority for the country that achieved it. Even back then it was clear that the power ruling the seas is the one ruling the world. Mahan, regarded as one of the greatest strategists of naval warfare, understood the significance of naval power for war, but more importantly – for the economy and civilian life.

With regard to the economic aspect, there is a big difference between a manned submarine and a UUV – the cost. The cost per unit will determine the country's acquisition capability. If one of the objectives of naval superiority is to defend commercial shipping through maritime routes, then the number of units will be of critical significance. You cannot secure a fleet of dozens or hundreds of merchant ships using just a handful of submarines.

The emergence of UUVs on the military naval arena a few years ago triggered a few alarms among the superpowers. Any person of a sound mind could have realized that this was a disruptive technology that would dramatically change the face of naval warfare. Consequently, we are currently witnessing several channels through which military technology associated with the underwater medium is evolving.

With regard to the offensive aspect, countries aspire to develop offensive UUV capabilities. Some of the objectives include disabling enemy ports and shipping routes, including the use of mines, attacks against offshore energy installations, attacks against enemy surface and underwater vessels, attacks against enemy coastal and airborne targets, as well as attacks against civilian infrastructures and undermining the economy of the enemy state.

Other development trends intended to achieve command of the sea include the use of multidimensional autonomous swarms. In other words – the future is in combining diving, floating, flight and ground travel capabilities in a single unmanned vehicle or in multiple vehicles operating together as a collective. Such a swarm will be able to accomplish every one of these objectives more effectively than the vehicles currently available, at a lower cost and without paying the political price of soldiers killed in action.

With regard to the defensive aspect, the growing awareness of the offensive threat imposed by UUVs compels countries (mainly the superpowers) to come up with suitable defenses. One of these defenses involves the deployment of an underwater network of sensors in all connected oceans and seas, with the purpose of eliminating the stealth advantage of underwater vessels, both manned and unmanned.

Some of these technologies involve linking of underwater sensors with buoys linked to satellites, with everything linked to a central command and control system. In this way, a superpower can achieve real-time situational awareness in the global naval arena. Such an ability, in wartime, will eliminate the enemy's stealth advantage.

Another trend involves floating (surface) platforms that detect and locate any submerged vessel and can respond to it. In most cases, these are unmanned floating vehicles fitted with a range of sonar devices for various depths (towed or fixed arrays). Such unmanned vehicles can scan an area cell at sea around the clock and establish circles free of underwater vessels around a point of interest (coastal border, offshore energy installation, island, etc.). In this activity, too, unmanned vessels will be the dominant factor in the coming years, and they are expected to substantially change the economic equation. Employing more vehicles will provide better underwater identification and consequently – more effective restriction of the operation of enemy submarines and UUVs.

Detecting Enemy UUVs

Yet another trend involves the use of UUVs for detecting enemy UUVs. In this way, a UUV school may be formed that would behave like a school of fish that 'lives' in a specific area cell. The school will be autonomous and will possess the ability to transmit video/sound/sonar data to a rear area command center, as well as the ability to respond (Kamikaze-style) so as to close the loop on an enemy UUV the moment it has identified such a vehicle. Such a school may also be used to deploy mines in area cells where no underwater activity is expected, to establish static prevention areas.

With regard to the intelligence gathering aspect, just like manned submarines, UUVs may also be used to collect intelligence based on the same capabilities outlined above, especially under the cloak of clandestine operation provided by the underwater medium. The advantage of UUVs stems from the fact that they can collect intelligence continuously over very long periods of time – longer than manned submarines. UUVs are cheap, and if a UUV breaks down, it will be replaced by another UUV – no need to repair. A technical failure or malfunction occurring opposite the enemy shore will neither put a large group of warfighters at risk nor will it require a complex rescue operation.

With regard to cyberspace, the USA has recently announced that their submarines take part in cyberattacks against enemy targets. Admittedly, no details were provided beyond that headline, but it is reasonable to assume that these attacks involve the electromagnetic spectrum (EW) and the information spectrum (data). UUVs may be used toward the same objectives. Disrupting or jamming computer systems, including deletion, alteration or stealing of the data they store or convey, can render the use of similar kinetic measures unnecessary.

The cost of UUVs will probably enable the employment of schools for intelligence gathering. This would provide intelligence gathering redundancy as well as improving collection effectiveness. When multiple-theater UUVs have been developed, they will be able to improve the efficiency of the intelligence gathering effort and reduce the cost/information ratio in all theaters.

The objectives of UUV employment necessitate the development of capabilities that would enable these vehicles to accomplish the missions assigned to them. As the medium involved is the underwater medium, which possesses unique characteristics, industries worldwide are currently busy developing several capabilities that would make this possible.

One of these capabilities is navigation. A UUV should be able to navigate independently under the sea, without being controlled remotely. It must be able to determine its own location, the location of the target, how to evade obstacles and select the route that best suits the nature of the mission at hand.

Along with navigation, underwater communication capabilities should be developed as well. As UUVs operate in a medium not penetrable by electromagnetic waves, standard communication devices are useless. Under the sea, it is all about soundwaves and how they propagate. If a school is to be assembled, then machine-to-machine (M2M) communication will be critical. On top of the navigation and communication layers, group behavior algorithms should be applied, just like in the air, on the ground or in space – except that here they should be adapted to the restrictions of the underwater medium.

In addition to the capabilities to be developed so that UUVs can accomplish the missions assigned to them, operational aspects should be taken into consideration as well. The first aspect is maintaining secrecy. We have already noted the defensive capabilities being developed, so with regard to the offensive or intelligence gathering aspects, evasive capabilities and methods of operation are required that would maintain the operation secret vis-à-vis similar defensive capabilities.

The Beginning of a Revolution 

The introduction of UUVs to the naval arena is undoubtedly a revolution in its infancy. While manned submarines will probably remain in service as a second-strike deterrent owing to their ability to launch heavy missiles, other missions are expected to trickle to the UUV category. These vehicles will be able to operate continuously without leaving the underwater medium and provide various advantages with regard to the offensive and intelligence gathering aspects.

Diverting the mission load from manned submarines to UUVs will lead to a reevaluation of the effectiveness of the naval intelligence array currently deployed to detect manned submarines (dedicated Radars, helicopters, mission aircraft and UAVs). The question of how effective this array will be in monitoring the underwater activity of UUV schools that never surface remains to be answered.

Another question that arises from this discussion is the dual use of UUVs. Over the last few years, an industry of research/scientific UUVs has developed. This industry is busy developing capabilities that are very similar to the needs of military UUVs. Navigation, communication, operation in schools, cutting-edge materials, underwater photography, transmitting video data to the rear area and integrating underwater repair resources in the UUV – all of these capabilities are being developed for marine research and are available to anyone involved in this field.

Moreover, countries use the pretext of marine research in order to test capabilities that they would eventually use in military vehicles. One such example was reported in December 2016, when China captured a US UUV that was engaged in research activity in the South China Sea. According to the Pentagon, the UUV "operated lawfully and was collecting data on the salinity, temperature and clarity of the water about 50 nautical miles to the north-west of Subic Bay in the Philippines." Will the cover of scientific research evolve into a double-edged sword that enables countries involved in terrorism to bridge their knowledge gaps through it?

This revolution calls for a conceptual revision among navies the world over. One of the questions each navy must ask itself involves the amount of resources to be allocated to the benefit of the UUVs at the expense of other platforms. This decision will be even more critical as multiple-theater unmanned vehicles are developed. If a navy wishes to benefit from the advantages of this technology in the context of strike and intelligence gathering activities, it will have to acquire a mass of vehicles and come up with creative methods of operation that would enable its vehicles to operate effectively opposite similar enemy vehicles. A navy that fails to embrace this revolution will be left with very limited capabilities and a crippled defensive setup incapable of dealing with future threats.


Yotam Gutman is a Major (res.) in the IDF Navy specializing in command, control and unmanned naval vessels.

The complete article can be found in issue 37 of Israel Defense magazine. To subscribe, click here.