Table of Contents

• Appendix
• 1. USA
  • 1.1 Attack submarines, SSN
  • 1.2. Ballistic missile submarines, SSBN
  • 1.3. Accidents
• 2. United Kingdom
  • 2.1 Attack submarines
  • 2.2 Ballistic missile submarines
• 3. France
• 4. China
• 5. India
• Endnotes

Appendix

Excluding Russia, there are at this time four countries with nuclear submarines in service: the United States, the United Kingdom, France and China. These four nations have a total of 133 nuclear submarines in operation. The USA and the Soviet Union/Russia have been the leading countries in developing new nuclear submarines. In the aftermath of the second World War it became obvious that the limiting factor in the further development of the submarine was the matter of fuel. Efforts were therefore focused on developing an alternative to the existing source of power, the diesel engine.

1. USA

In 1949, the United States Navy began to explore the possibility of utilising nuclear power in its submarines. Development work was headed by then Captain, now Admiral Rickover, and corporations such as Westinghouse, General Electric, Combustion Engineering and Babcock & Wilcox were important players in the process. To find the optimal reactor for use on board a submarine, full-scale test models of the different types of reactors were built on land. [609]

1.1 Attack submarines, SSN

The construction of the world's first nuclear submarine, USS Nautilus, began in the early 1950's. The USS Nautilus (SSN 571) was launched in 1954, and in 1957, was the first submarine to sail beneath the polar ice. The prototype was powered by a pressurised water reactor (type S2W) yielding 70 MWt[610] and transferring 7500 shp[611] to each of the two propellers.[612] USS Nautilus was followed by a second prototype, the USS Seawolf (SSN 575) which was equipped with a sodium cooled reactor. This reactor was designed to perform more efficiently within a smaller volume, but it turned out to be difficult to utilise. The reactor was later replaced by a pressurised water reactor.[613]

Based on the construction of USS Nautilus, a fleet of four Skate-class submarines were launched, offering the opportunity to experiment with different technologies. The first submarine of this class, the USS Skate (SSN 578), was the first submarine to surface at the North Pole.[614] The Skate class submarines were equipped with one pressurised water reactor, type S3W, giving a thermal power of 70 MWt. In this period (late 1950s), several different prototypes and reactor types were tested.[615]

The Skipjack class was the next class to be developed. The submarine hulls in this class were shaped like a tear drop, the so-called Albacore-shape. The shape of the hull, along with a type S5W pressurised water reactor with a thermal power of 70 MWt delivering 15.000 shp to the propellers,[616] combined allowed the submarine to travel at speeds exceeding 30 knots. The Skipjack class vessels were the fastest submarines of the period.[617]

Until the 1970s, the United States Navy predominantly used the S5W reactor. It yielded thermal power of 70 MWt, and was equipped with double steam generators, turbines and turbo generators.[618]

The next step was to develop submarines for the purpose of anti-submarine warfare, and to this end, the silent prototype USS Tullibee (SSN 597) was built. The prototype was fitted with a small reactor generating a power of 20 MWt and 2 500 shp.[619] There were considerable technical problems with this submarine, and the prototype was the only one built. However, the more successful technical aspects from the Tullibee project were used in later submarines.[620]

Following the USS Tullibee came a new class of silent and deep diving attack submarines, the Permit class. The first submarine in this class was the USS Thresher (SSN 593), equipped with the proven S5W reactor. The pressurised hull was made of HY80 steel, and the submarine had a maximum diving depth of 400 meters.[621] The submarine sank during a diving test on April 10, 1963, and all the crew were lost. The loss of Thresher led to modifications in the construction of this class of submarines. The next vessel was a modified version, the USS Permit (SSN 594), from which this class of submarines takes its name.[622]

The Permit class of attack submarines was followed by the Sturgeon class, which also used the S5W reactor.[623] The noise from these submarines was reduced in comparison to the Permit-submarines, but its top speed was only about 25 knots. Its maximum diving depth was 400 meters. There was a total of 37 submarines in this class.[624]

In 1976, the USS Los Angeles (SSN 688) was completed. She was the first of approximately 60 submarines in the silent Los Angeles-class. The class is equipped with a type S6G pressurised water reactor yielding 120 MWt, or 30 000 shp. This reactor is a modified version of the D2G-reactor used in nuclear destroyers from the early 1960s.[625] With this reactor, the submarine has a submerged maximum speed of 32 knots.[626] The increased maximum speed compared to the Permit/Sturgeon, led to a reduced maximum diving depth of 300 meters due to its thinner hull.[627]

1.2. Ballistic missile submarines, SSBN

The first nuclear powered ballistic missile submarine (SSBN) to be built in the United States, was the USS George Washington (SSBN 598), which for the most part was a modified Skipjack-submarine. The hull was extended to accommodate16 Polaris missiles. The first launch test was near Cape Canaveral, Florida, on July 20, 1960. A total of five submarines was built in this class. There were also five submarines in the Ethan Allen-class which was specifically designed to carry the Polaris missiles. These vessels were larger and quieter than their predecessors in the George Washington-class.[628]

In the succeeding class, the missile tubes were expanded to accommodate the newly developed Polaris A3 missiles, and the class would later also carry the Poseidon C3 and the Trident C4. The technology used in making the Permit class so silent was also installed. The first submarine in this class was the USS Lafayette (SSBN 616), from which the class takes its name.[629]. A total of nine Lafayette class submarines were built.[630]

The fourth generation of SSBN submarines was the Ohio-class, built to run as silently as possible. With a length of 170.7 meters and a displacement 18 750 tons, this is the largest submarine in the United States Navy. Originally, the class was to be powered with the same reactor as the Lafayette-class, the S5W-reactor, but the type S8G reactor was selected instead. This is a silent operating reactor with power of 220 MWt and 60 000 shp. The coolant circulates through natural convection.[631]

All submarines in this class are equipped with 24 Trident C-4 or Trident-II D-5 missiles. Plans originally called for 20 submarines in this class, but due to the START II-agreement, only 18 were built.[632]

1.3. Accidents

During a diving test on April 10, 1963, after a nine months maintenance period, the USS Thresher sank approximately 160 km east of Cape Cod, at 41:43'N, 64:57'W. The accident was probably caused by a water leak in the pipes in the engine room, preventing the submarine from rising to the surface.

The submarine was crushed by the water pressure, and is now lying in six pieces at a depth of 2600 meters. The entire crew of 129 was lost. There have been no attempts to raise parts of the submarine, but samples have been taken to check for leaks of radioactivity in the area. The samples indicate low concentrations of radioactivity in the sediments (12 Bq/kg ⁶⁰Co).[633]

The Skipjack class submarine, USS Scorpion, sank May 22, 1968 approximately 650 kilometres south-west of the Azores while heading from Gibraltar to Norfolk, Virginia. It sank at a depth of 3600 meters. The submarine was torn into two pieces, and there are speculations that the accident may have been caused by the explosion on board of one of the torpedoes. USS Scorpion's crew of 99 were all lost. In addition to the nuclear reactor, there were also two torpedoes with nuclear warheads onboard. Samples taken in the area indicate low levels of radioactive contamination in the sediments.[634]

2. United Kingdom

Development and research on nuclear submarines in the United Kingdom began in 1954. A land-based prototype reactor, called the DS/MP, was completed at Dounreay in Scotland in 1963. The United Kingdom has co-operated closely with the United States, and the first nuclear submarine of the Royal Navy was fitted with an American type S5W pressurised water reactor. The reactor was installed in the submarine HMS Dreadnought launched in 1963.[635] This submarine closely resembles the American Skipjack class.[636]

2.1 Attack submarines

The operation of the DS/MP reactor in Dounreay and experiences with the S5W reactor led to the development of the first generation of British pressurised water naval reactors, the PWR-1, with a thermal power of 70 MWt, and 15000 shp. This reactor was installed in the first generation of British nuclear submarines, the Valiant class, with the first being installed in HMS Valiant, from which the class takes its name.

The second generation of the PWR-1 reactor was installed in the Swiftsure-class, which went into service in 1973.[637] This class of submarines had a speed of just over 30 knots. At this time, there are five submarines of this class in operation.[638].

A third generation of the PWR-1 reactor was developed to prolong the operational life of the reactor core. This reactor was installed in the Trafalgar class, which began service in the late 1970s. Much effort was expended in reducing the noise of the submarine.[639] The Trafalgar class has a maximum speed of 32 knots,[640] and at present, there are seven vessels in active service.

2.2 Ballistic missile submarines

Based on the Valiant class, the Resolution class of submarines was developed in order to accommodate the Polaris ballistic missiles. The class was fitted with first generation PWR-1 naval reactors. The Royal Navy ordered four submarines of this type in 1963.[641]

In 1976, a new type of reactor was ordered so as to increase safety margins, ease inspection while in operation, and improve the power output. A land based prototype, the STF2, was built at Dounreay, and on this basis, a new reactor type, the PWR-2, was developed yielding a thermal power of 130 MWt and 27500 shp. This reactor was used for the first time on board a vessel of the Vanguard class, which is slated to replace the Resolution class of submarines. Vanguard class submarines are equipped with Trident missiles.[642]

3. France

Contrary to other countries which first of all developed nuclear powered attack submarines, the first efforts of France were directed into the building of a ballistic missile submarine. The French programme began in 1959. By 1964, there was a land-based prototype reactor ready at Cadarache in southern France. A reactor based on the prototype was installed in the first of the Le Redoutable class of ballistic missile submarines. Launched in 1969, the Le Redoutable generated 16000 shp with a top speed (submerged ) of 25 knots. A total of six submarines of this class were built until 1984. The Le Redoutable class was followed by the Le Triomphant class which is powered by a type K15 reactor yielding thermal power of 150 MWt and 41500 shp. [643]

The first class of French nuclear powered attack submarines was equipped with second generation reactors. The first submarine in this class was Le Rubis, from whence the class gets its name. With a length of 72.1 meters and a displacement of 2670 tons, this is the world's smallest nuclear powered submarine.[644] The submarines in the Le Rubis class have a top speed of 25 knots. At present, there are 6 operational submarines in this class, including Amethyste and Perle which are somewhat longer and of an improved design.[645]

4. China

China has a total of six operational nuclear submarines, five attack submarines and one ballistic missile submarine. The five attack submarines are of the Han class, and are fitted with a pressurised water reactor yielding 15000 shp. These submarines are quite noisy, and have a maximum speed of 30 knots. China's only ballistic missile submarine is of the Xia class, and is comparable to the Russian Yankee-II submarine. The Xia class submarine utilises the same type of reactor as the Han-submarine, and has a maximum speed of 20 knots. [646]

5. India

India is developing a nuclear powered submarine, most probably an attack submarine. The naval reactor for this submarine is being developed in co-operation with Russia.[647]

Table 11: Countries outside Russia with operational nuclear submarines[648]

Endnotes

[609] Eriksen, V.O., Sunken Nuclear Submarines, 1990; and Clancy, T., Submarine, 1993. Return
[610] Thermal power Return
[611] Shaft Horse Power Return
[612] Eriksen, V.O., Sunken Nuclear Submarines, 1990. Return
[613] Clancy, T., Submarine, 1993. Return
[614] Ibid. Return
[615] Eriksen, V.O., Sunken Nuclear Submarines, 1990. Return
[616] Ibid. Return
[617] Clancy, T., Submarine, 1993. Return
[618] Eriksen, V.O., Sunken Nuclear Submarines, 1990. Return
[619] Ibid. Return
[620] Clancy, T., Submarine, 1993. Return
[621] Eriksen, V.O., Sunken Nuclear Submarines, 1990. Return
[622] Clancy, T., Submarine, 1993. Return
[623] Eriksen, V.O., Sunken Nuclear Submarines, 1990. Return
[624] Clancy, T., Submarine, 1993. Return
[625] Eriksen, V.O., Sunken Nuclear Submarines, 1990. Return
[626] Jane's Fighting Ships, Recognition Handbook, 1994. Return
[627] Clancy, T., Submarine, 1993. Return
[628] Ibid. Return
[629] Ibid. Return
[630] Toppan, A., USN Submarine List, URL: http://www.wpi.edu/~elmer/, 1995 Return
[631] Eriksen, V.,O., Sunken nuclear submarines, 1990. Return
[632] Clancy, T., Submarine, 1993. Return
[633] Ølgaard, P.L., 1994. Return
[634] Ibid. Return
[635] Eriksen, V.O., Sunken nuclear submarines, 1990. Return
[636] Preston, A., 1980. Return
[637] Ibid. Return
[638] Jane's Fighting Ships, Recognition Handbook, 1994. Return
[639] Eriksen, V.O., Sunken nuclear submarines, 1990. Return
[640] Jane's Fighting Ships, Recognition Handbook, 1994. Return
[641] Eriksen, V.O., Sunken nuclear submarines, 1990. Return
[642] Ibid. Return
[643] Ibid. Return
[644] Clancy, T., Submarine, 1993. Return
[645] Jane's Fighting Ships, Recognition Handbook, 1994. Return
[646] Clancy, T., Submarine, 1993. Return
[647] Jane's, Jane's Fighting Ships, 1994. Return
[648] International Institute for Strategic Studies, 1995. Return