How could this be achieved? The answer was given at a state scientific centre called the Krylov Shipbuilding Research Institute (KSRI). Fourth-generation submarines are provided with specially developed noise-absorbing — down to low frequencies — rubber coatings only 40 mm thick. They are half as thick as those we used before. The new coating consists of 7 to 8 layers of rubber with different perforations and profiles. The idea is simple: the more air cavities there are, the more effectively they absorb noise of different frequencies and at different depths. This was said by Professor Ernst Myshinsky, Doctor of Engineering, head of the shipboard and industrial acoustics department.
But hydro-acoustic coating is only a passive defense against noise. And the Institute is already working on new tools for active defense. According to the scientist, development of such means of noise suppression is a super new direction in world science. In Russia the active methods appeared a quarter of a century ago, but then they were considered to be a "medicine", like nitroglycerin.
"Twenty-five years ago electronics was appalling. And we all feared that instead of creating an anti-sound — a sound in the anti-phase — we could knock out electronic controls. And the noise, on the contrary, would intensify," says Myshinsky. "But now electronics are normal, and so it is time to develop active comprehensive system of noise reduction."
It is possible that they may appear on the next submarine, which will be built after Sankt Peterburg.
Better Than Energiser
Stale TV advertising about batteries "that will work, work and work" would look deflated if developers of "hydrogen batteries" for the Sankt Peterburg boat dared to put their ware on the air waves.
Thirty years ago TsKB Lazurit, NPO Kvant and Kriogenmash embarked on the development for submarines of propulsive systems with electro-chemical generators, ECGs. The S-273 submarine of Project 613, which was mentioned above, was converted under Project 613E Katran. While conventional submarines at two-knot speeds could not stay under water for longer than four days without battery recharging, the use of electro-chemical generators increased this period to a month.
A second area in which Russian designers work is development of Diesels operating in a closed cycle. Project 615 with a single engine was put into metal in the middle of the last century and marked a unique event in the world.
Since 1978, the Special Boiler-Building Design Office has been the leading developer of propulsive systems with ECGs It drew on the experience of the Urals electrochemical works and NPO Energia that developed ECGs for spacecraft. In that way, a Kristall-20 engine for submarines made its appearance, using oxygen and hydrogen. The latter is present in bound form — in an intermetallic compound. Second-generation Kristall-27 and Kristall-273 engines can now also be installed on new Diesel-electric submarines, increasing their endurance to 45 days. Without divulging all secrets of Russian shipbuilding, we may say that the endurance of Sankt Peterburg is exactly 45 days.
Amur, Cousin of Lada
Just like the German Howaldtswerke Deutsche Werft AG, Admiralteiskiye Verfi, in parallel with the Lada class sub for the Russian Navy, is also building for export a fourth-generation submarine of Amur-1650 class. They are almost look-alikes. Amur will be able to fire missile salvoes against surface single and group targets. Compared with submarines of the previous projects, its acoustic signature is several times lower. It also carries radioelectronic equipment of a new generation.
Automatic ship control, and management of its combat and technical systems, will be effected from the main control room. An inertia navigation system will ensure safe navigation and determination of movement parameters while staying under water for a long time with an accuracy sufficient for missile weapons. Amur will have an all-mode propulsion electric motor of a new type, and also a storage battery with an extended service life.
Like Lada, the export unit is equipped with a highly sensitive array of the Lira sonar system. The outer hull is covered in Molniya anti-sonar coating of a new generation.
FGUP Admiralteiskiye Verfi is contributing financing to the development of an air-independent propulsion unit for use as an alternative source of electricity.
Everything for Sale
Admiralteiskiye Verfi has what financiers describe as a good credit history. By 2002, it had handed over to foreign clients thirteen submarines of Projects 877EKM and 636, i.e. more than half of boats of this class built in this country. At the same time, it repaired four vessels.
New output of the enterprise will also find its consumers. The most promising market, according to specialists, is South East Asia. Among the probable buyers of Amur-class submarines are Vietnam, Thailand, and the Philippines. Last century Russia sold about 50 submarines. It is not ruled out that in the 21st century products of Russian shipwrights will still be in demand on the international arms market.