In the Soviet Union the first designs to envision the use of nuclear power in submarines date back to the late 1940s. At the time, the Nuclear Energy Institute began to develop a 5,000-kwt reactor for the first Obninsk nuclear electric power plant in the world; it was believed that this uranium-graphite reactor would be suitable for ship propulsion as well. At the same time, Soviet ship designers attempted to determine what the nuclear submarine would look like.
The Soviet nuclear submarine project became a reality on 9 September 1952, when the U.S.S.R. Council of Ministers adopted a resolution on its development. The resolution, initiated by physicists working on nuclear weapons, was motivated by the fact that, although the first nuclear explosive devices were developed in the Soviet Union in 1949, there was a shortage of reliable and effective delivery systems. The U.S.S.R. did not have a viable strategic air force that could reach distant targets, and there were no aircraft carriers to take tactical bombers to the target. Missiles were in the initial stages of development and the results were modest in terms of both range and accuracy. Thus, nuclear-weapon designers focused on submarines, which could make undetected transoceanic journeys and attack the enemy homeland with short- and medium-range weapons.
V. A. Malyshev, Deputy Chairman of the Council of Ministers, was appointed to supervise the development of a nuclear submarine. In September 1952 the Chemical Engineering Research Institute organized two task forces, one for the submarine—headed by V. N. Peregudov, Assistant Director of Research Institute No. 45, Shipbuilding Industry—the other for the power plant—headed by N. A. Dollezhal, Director of the Chemical Engineering Research Institute. In view of the top secret nature of the project, the circle of the initiated was highly restricted. Even the heads of the organizations from which the project group was recruited did not know the goal of the work. Naval personnel were not permitted to take part in the work or in laying down the requirements for the first nuclear submarine. In addition to securing secrecy, this arrangement was intended to accelerate work, bypassing the traditional interdepartmental contradictions and obstacles. It was assumed that Peregudov, a naval officer and chief designer, would be able to combine the interests of both sides—the Navy and industry.
One of the central problems in the course of the work was the choice of nuclear power plant. Four types of reactors were considered: uranium-graphite, beryllium oxide delay mechanism, liquid- metal heat agent, and pressurized water. After a comparative analysis, the water reactor was selected because its size and weight were acceptable for a submarine and its development in the required time period involved less risk. Work on a liquid-metal heat agent reactor was carried on in an independent program.'
Time was one of the most important factors in designing and choosing the nuclear power plant. U.S. superiority in the nuclear field seriously concerned the Soviet leadership, and research was controlled at the highest level. Almost every week, the heads of groups and the scientific adviser reported on the work that had been done, which was then subject to the strictest scrutiny. Given that the Soviet nuclear program was supervised by the secret police chief, the psychological pressure was strong.
In March 1953, the submarine design group completed its preliminary research. The design they produced differed operationally from diesel-electric submarines. Taking into account the new submarine’s nontraditional task—to attack enemy coastal targets—the T-15 large-caliber torpedo (1.55-meter diameter, 24-meter length, and weighing 40 tons) carrying a thermonuclear device became its principal weapon. The submarine also would have two conventional 533-mm torpedo tubes for self-defense.
The nuclear power plant would provide for a speed of 25 knots, which could be sustained underwater for long periods. An unusual cigar-shaped hull resulted from the location of torpedo tubes in the bow and offered reduced resistance when the boat was transiting submerged. The submarine was to be equipped with a dual-shaft power plant and was to be able to travel underwater continuously for 50-60 days and dive to a depth of 250300 meters.
At the same time, some of the technical solutions were influenced by traditional approaches characteristic of diesel-electric submarines: the layout of the vessel remained the same, as well as the approach to survival, hull compartments, and the DC electrical system.
Full-scale development of the first nuclear submarine was assigned to Leningrad Special Design Bureau 143, and the project was designated 627 (known as November abroad). In March 1953, the bureau began designing the boat and organizing development of its equipment. Only 15 months later, the personnel of Special Design Bureau 143 completed blueprints and the technical designing. At the same time, research and development organizations in different industries carried out relevant experimental and design work to develop new equipment, weapons, and structural materials and technical solutions. An important role in the fulfillment of this work was played by the project’s scientific advisor, Academician A. P. Alexandrov.
The key task was to develop the ship’s nuclear power plant. This work was carried out under the scientific supervision of the Institute of Nuclear Energy. Actual development of the steam-generating plant VM-A was done by Research Institute No. 8 in conjunction with the Special Design Bureau of the Boiler Plant of the Baltic Shipyard. Pumps of the first circuit and the steam turbine were developed at the Leningrad Kirov Factory. The leading role in developing the turbine was played by mechanics from Special Design Bureau 143.
Lower diving depths made it necessary to use new high-strength steel and welding materials developed by Research Institute No. 48 of the shipbuilding industry. Research Institute No. 45 tested the strength of the hull, helped reduce vibrations in mechanisms and noise, and carried out hydrodynamics studies.
Experts of Research Institute No. 45 and the Central Aerohydrodynamic Institute of the Aviation Industry put the finishing touches on the hydrodynamics of the nuclear submarine, with its unconventionally shaped hull and conning tower. Decision making on hydrodynamics and coordination of experimental research was carried out by experts at Special Design Bureau No. 143. Although parallel work on the submarine introduced rivalry between the two scientific organizations, the results were complementary and raised the boat’s quality.
A major problem the designers encountered was to provide conditions for the crew’s activities on board during long periods under sealed conditions. A special system of air regeneration and conditioning was worked out and tested on the reequipped submarine D-2. The crew lived and worked on board this veteran boat for 50 days, isolated from the atmosphere.
Extensive work also was involved in creating the boat’s weapon system. Achievement of the required accuracy and effectiveness using T-15 torpedoes remained a stumbling block.
In July 1954, after the Project 627 design was completed, naval experts were acquainted with its details for the first time. After careful study, the group expressed doubt as to the submarine’s ability to carry out its main mission. Indeed, to attack a target, the submarine had to be about 40 kilometers from it and check its position according to coastal landmarks by means of radar before firing its nuclear torpedoes. Avoiding detection and retaining combat efficiency under the circumstances was virtually impossible in coastal areas with strong antisubmarine defenses. The naval experts concluded that the experimental submarine’s armament was useless.
In addition, the group’s report pointed to an insufficient full speed and weak self-defense weapons. Nevertheless, it emphasized the need to step up construction and trials.
In view of the experts’ report, changes were introduced, which Special Design Bureau 143 completed by mid-1955 with simultaneous reissue of blueprints. In the final version, the submarine was equipped with eight 533-mm torpedo tubes and 20 torpedoes instead of the T-15 torpedo and two smaller tubes. With these weapons the first Soviet nuclear submarine was reoriented to attack naval transport ships on sea lines of communication. The rejection of the T-15 torpedo also was justified by the development of a nuclear warhead for the 533-mm torpedo.
The revised Project 627 retained the same features as previous versions. It had a double elongated hull with a rounded bow. Its hull was divided into nine compartments. (See Figure 1.) The location of the nuclear power plant in the middle of the hull made it easier to trim the submarine and enabled the berthing and combat posts to be in the fore and aft compartments.
The Project 627 nuclear submarine was furnished with advanced observation, communication, and navigation equipment. Most of it had been used by naval personnel on Project 611 and 613 diesel submarines. In view of the much higher speed of nuclear submarines, automation was used in the steering systems.
Combat specifications of the submarine’s torpedo weapons were improved: for the first time it became possible to fire torpedoes at a depth of 100 meters. Nuclear power made submarines real underwater vessels, and nuclear boats discarded the legacy of attacking at periscope depth.
In designing the submarines, measures were taken to provide for acoustic concealment: mechanisms with reduced vibrations and noise and shock absorption were used, vibration-absorbing and antiradar (anechoic) coating was applied, and low-noise screws were installed. However, shock absorbers for the main turbines were never developed, and as a result, the underwater noise level of the Project 627 when moving at medium speed proved to be the same as that of a diesel when propelled by the main electric motors. The noise level of the nuclear submarine increased considerably at higher speeds.
At the time, acoustic concealment was not regarded by the designers as a top priority. They faced the task of making the boat independent of atmospheric air and, therefore, safe from detection by surface ship and aircraft radar. From that viewpoint, acoustic defense seemed sufficient. In addition, methods and means of acoustic defense in the early 1950s were not well developed.
Special Design Bureau 143 began to issue blueprints of the Project 627 submarine in March 1954, without waiting for completion and approval of the project or, as it turned out, its subsequent correction. In June of the same year, shipyard No. 402 in Severodvinsk began construction. To ensure secrecy, building hall No. 42, where the work was being done, was surrounded by a high fence, dubbed the “Wall of China,” forming an autonomous shipyard within the enterprise.
Simultaneously, in Obninsk, a land prototype of the boat’s nuclear power plant was created at the Physics and Energy Institute. It consisted of the submarine’s real reactor and turbine compartments in which the steam-generating and turbine units of the starboard side were installed. On 8 March 1956, the test reactor was put into operation. Subsequent research showed that the power plant’s equipment was efficient and the technical solutions were correct.
Parallel construction and testing were necessary because of the limited time available to finish the project, which was assigned national priority. Soviet leaders, including Nikita Khrushchev, repeatedly visited Shipyard No. 402. This attention facilitated the solution of arising problems, but at the same time it raised responsibility for the technical part of the program and the end result. The early deadline had another negative side: equipment supplied by other factories was not always sufficiently tried and tested, and many shortcomings had to be eliminated in the boat during trials or later operation.
The keel-laying ceremony of the Project 627 nuclear submarine was held on 24 September 1955. The boat was launched on 9 August 1957, and dockside trials began in September. The main focus was on the nuclear power plant. The boat’s reactors were put into operation on 14 September. The submarine crew, formed in 1956, took an active part in the trials.
In early July 1958, the Project 627 boat, which received the tactical designation K-3, was presented to the government commission for sea trials. At 1003 on 4 July 1958, the K-3 set out for the first time under nuclear power.
Testing of the nuclear power plant on the open seas was completed successfully. Nevertheless, it was decided to run the submarine nuclear plant at 60% power for safety’s sake until the end of trials in Obninsk. The boat reached a speed of 23.3 knots, 3 knots higher than expected. When operated at top power, the submarine’s speed reached 28-30 knots.
During trials the K-3 made five journeys and spent 25 days at sea. She dove 29 times and traveled 3,801 miles in 450 hours, including 860 miles underwater, with an average speed of 15 knots. During deep-water trials the K-3 plunged to a depth of 310 meters, a first for Soviet submarines. In speed and diving depth the Project 627 submarine exceeded the first U.S. nuclear submarine, Nautilus (SSN-571).
At the same time the K-3 trials showed some shortcomings in the nuclear plant design. Unreliable steam generators were the main problem of the first Soviet nuclear submarines. To eliminate the leaks, it was necessary to change the design of the steam generators, select new materials, and improve the system conditioning water for the nuclear plant.
While the generator problem was being solved, the situation in nuclear submarine building was extremely tense. New submarines were being commissioned, but their regular operation was restricted; they could make only short cruises. As a result, the full burden of confrontation at sea, even during the Cuban Missile Crisis in 1962, was borne by diesel submarines. Nevertheless, in the early 1960s—the generator problem solved— the Arctic expeditions by the K-3 and later nuclear submarines restored the reputation of the nuclear submarine fleet.
In mid-1962 the K-3 was prepared for a journey to the North Pole. Her superstructure was reinforced, special radar was installed to detect open water in icebound areas, and high-latitude navigational equipment and underwater TV were added. The boat left her Arctic base on 11 July and began its journey under the ice three days later. On 15 July the K-3 surfaced in an open space at a latitude of 84° and raised the Soviet flag on the ice.
On 17 July 1962, at 0655, the K-3 passed the geographical point of the North Pole underwater but was unable to surface because of the 12-meter thick ice. During this cruise, K-3 traveled 3,115 sea miles, including about 1,300 miles under the ice. On 21 July 1962, the K-3, soon to be named Leninsky Komsomol, returned to her base to a hero’s welcome.
Following this expedition the K-3 continued in service in the Northern Fleet. The submarine repeatedly made long journeys and took part in fulfilling combat missions.
Such was the result of the enormous work carried out by thousands of shipbuilders, scientists, engineers, and workers and the skill and courage of sailors. On the whole, 135 enterprises, including 20 design bureaus, 35 research institutes, and 80 factories took part in creating the first nuclear submarine. In just six years, the country carried out a task comparable in innovation and scale with the development of the first spacecraft.
On 22 October 1955, the Council of Ministers adopted a resolution approving development of series Project 627A submarines. The lead boat, the K-5, was laid down at Shipyard No. 402 in August 1956, was launched in September 1958, and commissioned in December 1959. In total. Shipyard. No 402 built 12 submarines between 1956 and 1964.
Beginning in 1963, the Project 627A submarines carried out a number of long expeditions. In September 1963 the K-115 made a trans-Arctic cruise under the ice from the Barents Sea to the Pacific Ocean. On 29 September, the K-181 surfaced at the North Pole. In 1966 the K-133 made an around-the-world underwater trip, traveling about 20,000 nautical miles in 54 days.
On a par with these cruises, the 627A Project submarines fulfilled everyday combat missions, defending the Soviet Union’s state interests.
This type of reactor was used in the Project 645 submarine K-27, a modified November (627A), and the Alfa (Project 705).
Mr. Antonov is an engineer and deputy head of the design department of the Malachite Design Bureau in St. Petersburg. He has participated in the design of several advanced, nuclear-propelled attack submarines, as well as studies for submarine tankers.