An SSN is a nuclear-powered general-purpose

attack submarine An attack submarine or hunter-killer submarine is a submarine specifically designed for the purpose of attacking and sinking other submarines, surface combatants and merchant vessels. In the Soviet and Russian navies they were and are called ...

. ''SSN'' is the US Navy hull classification symbol for such vessels; the ''SS'' denotes a

submarine A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...

and the ''N'' denotes

nuclear power Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced b ...

. The designation SSN is used for interoperability throughout

NATO The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two N ...

under

STANAG In NATO, a standardization agreement (STANAG, redundantly: STANAG agreement) defines processes, procedures, terms, and conditions for common military or technical procedures or equipment between the member countries of the alliance. Each NATO st ...

1166, though navies use other terms.

History

The first nuclear-powered attack submarine was the US Navy's , operational from 1954. This was followed by the four submarines of the entering service in 1957. The Royal Navy's first nuclear fleet submarine was which by using an American reactor entered service in 1963. The first all-British nuclear submarines were the two s. The USN submarine fleet has been all-nuclear powered for over two decades. The bulk of the USN's SSN fleet has been the ''Los Angeles''-class attack submarine. Designed during the

Cold War The Cold War is a term commonly used to refer to a period of geopolitical tension between the United States and the Soviet Union and their respective allies, the Western Bloc and the Eastern Bloc. The term '' cold war'' is used because t ...

the ''Los Angeles''-class boats ''raison d'etre'' was to protect USN

carrier battle group A carrier battle group (CVBG) is a naval fleet consisting of an aircraft carrier capital ship and its large number of escorts, together defining the group. The ''CV'' in ''CVBG'' is the United States Navy hull classification code for an ai ...

s and to hunt Soviet Navy SSBNs before they could launch a first strike against the United States. The first ever major combat action involving an SSN was during the 1982

Falklands War The Falklands War ( es, link=no, Guerra de las Malvinas) was a ten-week undeclared war between Argentina and the United Kingdom in 1982 over two British dependent territories in the South Atlantic: the Falkland Islands and its territorial ...

. An Argentinian cruiser, was sunk by

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, ...

es fired by the Royal Navy fleet submarine . After that incident, the Argentinian Navy was effectively confined to port. Since the end of the Cold War, SSNs have evolved into multi-mission submarines. Their roles include submarine-launched

cruise missile A cruise missile is a guided missile used against terrestrial or naval targets that remains in the atmosphere and flies the major portion of its flight path at approximately constant speed. Cruise missiles are designed to deliver a large warh ...

platforms, intelligence gathering platforms, insertion and exfiltration of special forces teams in addition to traditional hunter-killer SSN roles. The advantages of an SSN over a conventionally powered SSK are much longer endurance (limited more by the crew than the boat, a nuclear submarine can stay submerged for months and does not need refueling in their 25-year lifespans), and higher speed. Unlike most SSKs, SSNs do not have to surface periodically for air, which would compromise their stealth. Some of the newest conventional submarines approach these advantages:

Stirling engine A Stirling engine is a heat engine that is operated by the cyclic compression and expansion of air or other gas (the ''working fluid'') between different temperatures, resulting in a net conversion of heat energy to mechanical work. More specif ...

powered vessels can cruise underwater for up to two weeks and, like diesel/electric vessels (and in theory

LOX Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an appli ...

powered vessels), are significantly quieter than nuclear submarines, since they do not need to run the powerful (and noisy) pumps associated with the cooling circuits of pressurized water reactors. The main disadvantages of an SSN are the technological challenges and expenses of building and maintaining a

plant. Nuclear submarines can have political downsides, as some countries refuse to accept nuclear-powered vessels as a matter of policy. Furthermore, decommissioned nuclear submarines require costly dismantling and long term storage of the

radioactive waste Radioactive waste is a type of hazardous waste that contains radioactive material. Radioactive waste is a result of many activities, including nuclear medicine, nuclear research, nuclear power generation, rare-earth mining, and nuclear weapons r ...

. The following navies currently operate SSNs: * People's Liberation Army Navy of China *

French Navy The French Navy (french: Marine nationale, lit=National Navy), informally , is the maritime arm of the French Armed Forces and one of the five military service branches of France. It is among the largest and most powerful naval forces in t ...

Indian Navy The Indian Navy is the maritime branch of the Indian Armed Forces. The President of India is the Supreme Commander of the Indian Navy. The Chief of Naval Staff, a four-star admiral, commands the navy. As a blue-water navy, it operates si ...

* Russian Navy *

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against ...

of the United Kingdom *

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

Active and future SSN classes

;

Royal Australian Navy The Royal Australian Navy (RAN) is the principal naval force of the Australian Defence Force (ADF). The professional head of the RAN is Chief of Navy (CN) Vice Admiral Mark Hammond AM, RAN. CN is also jointly responsible to the Minister of ...

* Australian Nuclear Attack Submarine - At least 8 planned ;

Brazilian Navy ) , colors= Blue and white , colors_label= Colors , march= "Cisne Branco" ( en, "White Swan") (same name as training ship ''Cisne Branco'' , mascot= , equipment= 1 multipurpose aircraft carrier7 submarines6 frigates2 corvettes4 amphibious war ...

* ''Álvaro Alberto''-class submarine - 1 under construction ; People's Liberation Army Navy of the People's Republic of China * ''Han''-class submarine (Type 091) - 3 in service, 2 retired * Type 093 submarine - 6 in service * Type 095 submarine - 5 planned in total ;

* - 5 in service, 1 retired * ''Barracuda''-class submarine - 1 in service, 6 planned in total ;

* - 1 was in service, but returned to Russia in June 2021 before end of lease 1 more submarine leased to be delivered by 2025 * Project 75 Alpha - 6 planned in total ; Russian Navy * Victor III-class submarine - 3 in service, 45 retired * Sierra II-class submarine - 2 in service * - 10 in service, 4 retired * ''Yasen''-class submarine - 1 in service, 12 planned in total ;

of the United Kingdom Known as "fleet submarines" in the Royal Navy Astute2cropped

* - 3 in service, 4 retired * - 4 in service, 7 planned in total *

SSN(R) The Submersible Ship Nuclear (Replacement) or SSN(R) (also known as the Maritime Underwater Future Capability (MUFC)) is a planned class of nuclear-powered fleet submarine ( SSN) intended to enter service with the United Kingdom’s Royal Nav ...

- First design contract awarded ;

* - 30 in service, 32 retired * - 3 in service * - 19 in service, 48 planned in total

Retired SSN classes

;

* INS ''Chakra'' - leased

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...

Charlie-class submarine The Project 670 ''Skat'' submarine (NATO classification Charlie class) was a nuclear-powered cruise missile submarine built for the Soviet Navy and later operated by the Russian Navy. All Charlie I/II-class submarines are decommissioned. One ...

commissioned between 1987 – 1991. ;

of the United Kingdom * - the Royal Navy's first nuclear-powered fleet submarine 1963 - 1980 * - 2 submarines in service 1966 - 1994 * - 3 submarines in service 1970 - 1992 * - 6 submarines 1973-2010 ;

/ Russian Navy *

November-class submarine The November class, Soviet designation Project 627 Kit (russian: Кит, , whale, NATO reporting name November) was the Soviet Union's first class of nuclear-powered attack submarines, which were in service from 1958 through 1990. All but one h ...

1958-1991 * K-278 ''Komsomolets'' - only member of the "Mike" class, 1984 - 1989 (sank after fire) *

Alfa-class submarine The Alfa class, Soviet designation Project 705 Lira (russian: Лира, meaning "Lyre", NATO reporting name Alfa), was a class of nuclear-powered attack submarines in service with the Soviet Navy from 1971 into the early 1990s, with one serving ...

;

* (unique) * (unique) * - 4 submarines in service 1957 - 1989 * - 6 submarines in service 1959 - 1990 (One lost, 1968) * USS ''Triton'' (SSN-586) (unique) * USS ''Halibut'' (SSN-587) (unique) * - 14 submarines in service 1961 - 1996 (One lost, 1963) * (unique) * - 37 submarines in service 1967 - 2004 * (unique) * (unique)

References

{{DEFAULTSORT:Ssn (Hull Classification Symbol) Attack submarines

History

Active and future SSN classes

Retired SSN classes

See also

References