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Project 945 Barracuda / Sierra class
Attack Submarine (Nuclear Powered)

The Sierra class has a light and strong titanium pressure hull, enabling these boats to dive to depths of up to 550 meters (1800 feet) and enhancing their survivability, as well as having a low magnetic signature. Designed to engage surface task forces and launch cruise missiles at coastal facilities, the Sierra Project 945 class submarines represented the apex of Soviet attack submarine design. Project 945 was initiated in March 1972, under the direction of Chief designer N.E. Kvasha of TsKB-112 Lazurit. The new Sierra-class submarines were intended to be the primary Soviet attack submarine, incorporating a variety of new sensors, silencing equipment, command systems and countermeasures. The Sierra-class uses a single OK-650 pressurised water reactor, of the same model used in Project 971 (Akula) and on the Mike class submarine Komsomolets.

The Project 945 was generally comparable in performance to early Los Angeles class, though with an arguably superior non-acoustic detection system and integrated acoustic countermeasures system. They were apparently based on the design experience gained with the Project 685 Plavnik [Alfa], although a much larger torpedo room with capacity of up to 40 rounds was provided. Noise levels were reduced by Cluster Guard anechoic tiles on the outer hull.

The boat is outfitted with six 533 mm torpedo tubes capable of using a combination of Granat cruise missiles, torpedoes, antisubmarine missiles, and mines. As with the Alfa, the hull is constructed of titanium alloy, providing deep diving capability and the ability to avoid magnetic anomaly detection. The Sierra-I class had six major compartments: (1) the torpedo room, and battery, (2) crew quarters, officers mess and galley, (3) command center, computer complex, and diesel generators, (4) reactor, (5) main switchboard, pumps and geared turbines, (6) electric motors, steering gear and pumps. The double-hull reduces possible damage to the inner hull's compartments, and the outer hull is coated with anti-hydroacoustic materials making the Sierra more difficult to detect. A crew escape chamber is capable of bringing up the entire crew from a depth of 1,500 meters.

The Sierra-II was an improved and slightly version of the 'Sierra-I' class. The 945.A project (Sierra II) differs from the Sierra I in that the sonar capability of the Sierra II is better and has a reduced acoustic signature. It is five meters longer overall, with a larger blunt sail that is six meters longer than the Sierra I sail. The enlarged sail accommodates two rescue chambers, versus the single chamber on the Sierra-I. The increased hull size provided improved living quarters and quieting measures. It was also equipped with a new American-style spherical bow sonar. This filled the bow section, and the torpedo tubes were moved farther aft and angled out from the centerline. The torpedo room was modified to accomodate the S-10 Granat strategic cruise missile. In contrast to the six compartments on the Sierra-I, the Sierra-II had seven compartments: (1) the torpedo room, and battery, (2) crew quarters, officers mess and galley, (3) sonar room and command center, (4) computer complex, and diesel generators, (5) reactor, (6) main switchboard, pumps and geared turbines, (7) electric motors, steering gear and pumps.

A fundamentally important element of the new APL was the use for the manufacture of a durable titanium alloy body with a yield strength 70 - 72 kgf / mm2, which ensures an increase in the limit depth of the immersion by 1.5 times compared with the sub-generation submarine. The use of a titanium alloy of high specific strengths allowed due to a decrease in the mass of the body to save on water-displacement of the boat to 25 - 30%, which made it possible to build an apple in bitter and transporting its inner waterways. In addition, the titanium design allowed dramatically to reduce the magnetic field of the ship (according to this parameter, the atoms of the 945 project retain the world leadership among submarines and at present).

However, the use of titanium led to a significant increase in the cost of the submarine and for technological reasons limited the number of ships under construction, as well as the number of shipbuilding enterprises participating in the program (technology purchases of titanium buildings were not mastered in Komsomolsk-on-Amur). Compared to the episoda of the previous generation, the Torpedo-missile complex of the new boat was to have half an enlarged ampace, an improved target designation system, an increased shooting range (three times for rocket-torpedo and 1.5 times - for torpedoes), as well as increased combat readiness ( The time of preparation for shooting the first volley was reduced by two times).

In December 1969, the OKB of Minaviaprom "Novator" under the leadership of the main designer L. V. Lulieva began work on the creation of new antiquity missile systems for the second generation "Waterfall" (caliber 533 mm) and "wind" (650 mm) intended for the first The queue for equipping the promising third-generation submarine. Unlike its predecessor, PLRK "Vyuga-53", "Waterfall" was to be equipped with both a special combat part and a self-equipped small-sized torpedo UMGT-1 (developer - Uranus NGO) with a response range of the acoustic channel 1.5 km , travel range up to 8 km and the maximum speed of 41 bonds. The use of two types of configuration significantly expanded the range of weapons. Compared to the Vyuga-53 complex, the maximum launch start depth (up to 150 m) has increased dramatically (up to 150 m), the range of shooting ranges increased (from depths of 20-50 m - 5 - 50 km, from 150 m - 5 - 35 km ), the pre-training time has been significantly reduced (10 seconds).

"Wind" having twice as large than the "waterfall", the maximum range and depth of the launch, could also be equipped with both Torpeda UMGT and nuclear warhead. The complex "Waterfall" under the index of the RPK-6 entered the Navy in 1981 (they were equipped with not only submarines, but also surface ships), and "Wind" (RPK-7) - in 1984. Another new type of weapon embedded on the third-generation submarine has become a tele-controlled self-watering in two TEAD-71 torpedo planes. It was designed to defeat submarines and is equipped with an active-passive hydroacoustic homing system, which, together with a television management system, provided a targeting on a target in two planes. The presence of a television management system made it possible to monitor the maneuvering of the torpedo and the work of the appointment tours, as well as to manage them during the shot. The operator on board the APL, depending on the developing tactical situation, could prohibit the homing of torpedo or to change it.

The electric power unit provided the torpedo movement in two modes - search (at a speed of 24 knots) and rapprochement mode (40 knots) with repeated mode switching modes. The maximum range of travel (depending on the prevailing speed) was within 15 - 20 km. The depth of search and defeat the target was 2 - 400 m. In terms of the installation of the use of TEST-71, the American torpedo with MK.48 with a piston engine was significantly superior, although the latter, with a comparative range, had a slightly greater speed (50 nodes). To illuminate the underwater and surface atmosphere and target designation, it was decided to replace an improved hydroacoustic complex (GAK) MGK-503 "Skat". Thanks to measures to reduce the noise of the Apple and reduce its own interference when the GAK is running, the range of detection of goals compared to the second-generation submarine increased more than twice. New RES systems made it possible to reduce the error in determining the place 5 times, as well as significantly increase the intervals between the floors to determine the coordinates. Communication range increased by 2 times, and the depth of radio signals is 3 times.

The APL of the 945th project is intended to be configured not only to counter enemy rocket submarines, but also with surface ships from the composition of aircraft carriers and shock groups. The increase in combat potential was achieved by strengthening rocket and torpedo armaments, progress in the development of detection systems, targeting, communications, navigation, the introduction of information and control complexes, as well as improved main tactical and technical elements - speed, depth of dive, maneuverability, secrecy, reliability and survivability.

The submarine of the project 945 is made on a two-hull scheme. The light housing has an ellipsoid nasal and spine-like feed tip. The closure of the limber holes is carried out with the help of tagging shutters and kingstones on all the main ballast tanks. A durable case has a relatively simple formation - a cylindrical middle part and a conical tip. End bulkheads - spherical. The design of the mounting to the body of durable tanks eliminates the flexural voltages arising from the compression of the boat at a depth. The boat housing is divided into six waterproof compartments. There is an emergency blowing system of two tanks of the main ballast using solid fuel combustion products. The crew of the boat is 31 officer and 28 Michmanov, for which there are relatively good conditions of inhabitancy. The APL is equipped with a pop-up rescue chamber that can accommodate its entire crew.

Main energy setting with a nominal capacity of 43,000 liters. from. Includes one water-water reactor OK-650A (180 MW) and one parsoous unit. The OK-650A reactor has four steam generator, two circulation pumps for the first and fourth contours, three pump pumps. A steam monomial block pair-turbine plant has a wide reservation of the composition of the mechanization. The boat is equipped with two alternating current turbogenerators, two nutrient and two condenser pumps. To maintain direct current consumers there are two groups of batteries and two reversible converters.

The screw has improved hydroacoustic characteristics and a reduced frequency of rotation. In case of failure of the main energy installation, emergency sources of electricity and reserve means of movement are provided for the subsequent input. There are two DG-300 diesel generators with reversible transducers (2 x 750 liters.) With a fuel reserve for 10 days of work. They are designed to generate a DC for rowing electric motors and alternating - for general worked consumers. To ensure movement under water at a speed of up to 5 nodes of the APL, equipped with two rowing electric motors with a capacity of 370 kW, each of which runs onto its screw.

The boat is equipped with a hydroacoustic complex MGK-503 "Skat" (with analogue processing). Complex Communication "Lightning-M" includes a system of satellite communications and towed antenna "Paravan". A set of rocket-torpedo weapons and a combat information and control system provide a single and volleune shooting without restrictions on the depth depth (up to the limit). In the nose of the case, four 533-millimeters and two can caliber 650 mm are installed. The ammunition includes up to 40 units of weapons - rocket-torpedoes and torpedoes. Alternative option - up to 42 minutes.

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Page last modified: 19-12-2021 19:00:09 ZULU