Specialists of the St. Petersburg Marine Engineering Bureau "Malakhit" are developing a project for a small coastal submarine P-750B "Serval" with an air-independent (anaerobic) power plant (VNEU).

Igor Karavaev, the lead designer of Malakhit, spoke about this in an exclusive commentary to RT.

“In principle, the Serval can go to the ocean area, but the main task of the submarine is watch in shallow seas and coastal waters, that is, work where it is often difficult for large submarines to operate.

Specifically, these are the Baltic, Okhotsk, Barents and Black seas.

Also "Serval" is well suited for providing anti-submarine defense of our bases, "said Karavaev.

The materials of Malachite say that Serval is capable of striking stationary coastal targets, fighting enemy ships and submarines, patrolling and covertly transporting reconnaissance and sabotage groups.

The normal displacement of the promising submarine P-750B is about 1450 cubic meters.

m, length - 65.5 m, width - 7 m, draft - 5.2 m, maximum immersion depth - 300 m, full speed - 18 knots (33.3 km / h), autonomy - up to 30 days, total cruising range - within 4.3 thousand nautical miles (almost 8 thousand km).

The design office plans to achieve a high degree of automation of management processes in Serval.

Thanks to this, only four officers, with a total crew of 18-20 people, will be on watch at a time.

Liquid oxygen

As noted in "Malakhit", the choice of anaerobic power plant is dictated by a number of serious shortcomings of submarines with traditional diesel-electric units.

“Yes, in terms of cost-effectiveness, diesel-electric submarines are still second to none.

But their critical problem remains the need to ascend to recharge their batteries.

This means a loss of stealth and the risk of becoming an easy target for anti-submarine forces.

In addition, VNEU is generally safer and more environmentally friendly, ”explained Karavaev.

  • Model of a modernized small submarine developed by SPMBM "Malachite"

  • © Alexey Zakvasin / RT

The anaerobic installation, which Malachite expects to develop in cooperation with other Russian enterprises, will provide the carrier with a continuous underwater range of up to 1.2 thousand nautical miles (just over 2.2 thousand km).

Moreover, in terms of a number of qualitative characteristics, the Russian VNEU should surpass the analogs that are now installed on the submarines of the naval forces of foreign states, including NATO member states.

“VNEU of our western colleagues operate on a fuel cell or an electrochemical generator.

They have their advantages, but such installations suffer from insufficient power.

As a result, the submarines have to walk a lot at low speed and constantly charge the batteries, ”explained Karavaev.

According to the designer, another significant drawback of Western anaerobic plants is the use of hydrogen as an energy component.

“The presence of hydrogen on a submarine is very undesirable, since it forms an explosive mixture when it interacts with oxygen.

In the event of an accident, the crew's chances of survival are minimal.

In addition, the use of hydrogen requires serious financial costs, ”said the designer.

VNEU, offered by Malakhit, will be designed based on the technology of using closed-cycle gas turbines or a single gas turbine power plant.

This approach provides for the abandonment of the use of hydrogen - instead of it, liquid oxygen is used.

In addition, "Serval" is capable of continuing combat duty with fully discharged batteries for a certain period of time, added Karavaev.

Structurally, the Servala anaerobic plant consists of a hot loop, where gas exchange and cooling of the gas mixture takes place, and a section for utilizing waste gases.

The operation of the anaerobic plant is based on a scheme for converting chemical energy into heat, which in turn is converted into electrical energy, Pavel Andreev, design engineer of the 1st category of Malachite, explained in an interview with RT.

“The principle that we propose to use, a priori, slightly reduces the efficiency (efficiency. -

RT

) in comparison with traditional VNEU.

But energy losses with our conversion scheme are inevitable.

The gain here is in higher power, turbine reliability and operational safety, ”Andreev noted.

  • Building of SPMBM "Malachite"

  • © Wikimedia Commons

Also, VNEU "Malachita" should surpass the quality parameters of lithium-ion batteries, which are equipped with modern Japanese diesel-electric submarines of the Soryu class.

The main advantage of such submarines is the release of a large volume of internal space.

“Indeed, all VNEUs are large enough - this is their obvious drawback.

It would seem that lithium-ion batteries can easily solve this problem, but their operation raises a lot of questions, primarily due to the high probability of a short circuit, which can occur due to high heating.

And the consequences of the fire on the submarine are well known to everyone, ”stated Andreev.

According to him, the operation of submarines with VNEU on liquid oxygen will require the purchase of additional equipment, but will not entail a radical restructuring of the naval infrastructure.

In addition, according to the specialist, "Serval" will not be a difficult product in mass production in comparison with other non-nuclear submarines.

Modular architecture

Many innovations "Malachite" intends to integrate into the arsenal of "Serval".

So, the front part of the P-750B submarine will be designed to install several modules with weapons.

The choice of each one depends on the specifics of the task at hand.

For example, if it is required to strike at ground and sea targets, then a module with six outboard launchers for the use of torpedoes and Kalibr cruise missiles is mounted on the Serval.

“We have located the weapons bay outside the rugged hull.

In classic diesel-electric submarines, it is embedded, that is, welded into a sturdy hull.

From our point of view, this approach does not meet modern security measures too much, ”Andreev emphasized.

Also on "Serval" you can install the midget submarine "Triton", which can accommodate up to six combat swimmers.

This family of small-sized submarines appeared in the Soviet years, but by now the design bureau has modernized them.

"Tritons" are designed to carry out sabotage, reconnaissance and special operations in coastal areas.

In recent years, to ensure the covert transportation of combat divers, "Malachite" has developed and then finalized the submarine of Project 865 "Piranha", capable of covering up to 1,000 nautical miles (1,852 km).

The submarine's autonomy is 10 days, the maximum immersion depth is 200 m.

At the X International Maritime Show in St. Petersburg at the end of June, Malachite presented a mock-up of the Piranha torpedo modification with significantly increased autonomy and cruising range.

It is proposed to equip the submarine with mines and torpedoes of 533 and 324 mm caliber.

Another significant feature of the Serval's arsenal is a separate mine-dropping device.

“On modern submarines, sea mines are often dropped from torpedo tubes.

But this is a rather noisy process - there is a high risk of detecting a submarine.

Our device works very simply: the bottom cover opens, the stopper is lowered, and the mine quietly sinks to the bottom under its own weight, "said Karavaev.

  • Model of the modernized midget submarine "Triton" at IMDS-2021

  • © Alexey Zakvasin / RT

In an interview with RT, Dmitry Litovkin, editor of the Nezavisimoye Voennoye Obozreniye newspaper, noted that Malakhit and other domestic enterprises have the competence to create such a high-tech submarine as Serval.

“The small submarine Malachita is more interesting and more perfect than the diesel-electric Varshavyanka, and the Russian shipbuilding industry is undoubtedly capable of implementing this project in iron.

The position of the Navy is another matter.

At the moment, we do not have information about how the military themselves assess the Serval, and whether they are ready to buy these submarines, "says

Litovkin.

According to the expert, if the command of the Navy still supports the P-750B project, then the small submarine "Malachita" with a high degree of probability will gain great popularity not only in the domestic but also in the foreign market.

Military expert Alexei Leonkov also believes that Serval will be of interest to a significant number of Russian partners in military-technical cooperation.

This type of submarine is well suited for performing tasks in the coastal waters of different regions of the world, an expert said in a conversation with RT.

“Despite the modest autonomy of navigation, the Serval can quite effectively operate in the near sea zone, guard the borders, economic resources, and act as a deterrent to the navies of unfriendly countries.

This is a rather formidable naval technology, which, in my opinion, is in demand both in the Russian fleet and in the navies of other states that have access to shallow seas, ”concluded Leonkov.