Russia is developing a new generation of ultra-quiet nuclear submarines that are expected to pose a serious challenge to competing navies.

The new classes of subs — the Borey-A and Yasen-M — are said to be invisible to U.S. and NATO sonar aboard allied submarines, anti-submarine aircraft, and warships:

The submarines will be equipped with new, sealed pumps. The circulation of liquids in the submarine’s reactor, the cooling of its systems and equipment, the submarine’s surfacing and diving, and, most importantly, the filling of torpedo launch tubes with water before firing all depend on the pumps.

The technical characteristics of these new noiseless sealed pumps are top secret, since they define the physical portrait of each particular submarine. If these parameters become known, the submarine can be easily detected against the background of natural noises in the ocean.

In addition to noiseless pumps, these Russian submarines will be equipped with “wet” mufflers to fire torpedoes. New torpedo launch tubes have also been designed to make Russian submarines invisible. They work the same way as silencers on small arms; they drown out the sound of the shot.

According to Izvestia, the new pumps “have a simple design, small dimensions, and improved vibro and sound insulation.” Working at full capacity, one of these pumps can hold a mid-size coin standing on its edge of its lid.

The Kremlin is expected to build 5 Borey-A and 6 Yasen-M class nuclear submarines by 2020.

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