Ballistic missile submarine





A ballistic missile submarine is a submarine equipped to launch submarine-launched ballistic missiles (SLBMs) with nuclear warheads. In the US Navy they have the designation SSBN and they are nicknamed 'boomers', a common term of art used in everyday briefings and base operations. Virtually all ballistic missile submarines are nuclear powered and are therefore nuclear submarines.

History
The world's first ballistic missile submarine was a Soviet converted Zulu class submarine equipped with a single ballistic missile launch tube in its sail. The first SSBN class was a Skipjack class fast attack submarine with a 130 ft missile compartment welded into the middle. Several navies had previously made experimental trials with deck launched missiles. (See Regulus missile and related articles)

The first nation to field ballistic missile submarines was the Soviet Union. Its first successful submarine launch of a ballistic missile was on 16 September 1955 followed in 1956 by modifying the design of several Zulu class diesel powered attack submarines and installing an extra compartment containing two large vertical ballistic missile launch tubes in the middle with the launchers incorporated in the fin/sail. This was followed by a series of specifically designed Golf class units complemented by the nuclear-powered Hotel class, with both classes having three vertical launch tubes incorporated in the sail/fin of each submarine. The initial SS-N-4 ballistic missiles could only be launched with the submarines on the surface but were soon followed by SS-N-5 missiles which were launched with the submarine submerged. The Soviet analogue to the US SSBNs, the Yankee class SSBN with sixteen missiles, began to be built in 1964.

The US Navy fielded the first fleet of its operational missile subs, the George Washington-class submarine in the early 1960s.

Purpose
Ballistic missile submarines differ in purpose from attack submarines and cruise missile submarines; while attack submarines specialise in combat with other naval vessels (including enemy submarines and merchant shipping), and cruise missile submarines are designed to attack large warships and tactical targets on land, the primary mission of the ballistic missile is nuclear deterrence. Accordingly, the mission profile of a ballistic missile submarine concentrates on remaining undetected, rather than aggressively pursuing other vessels. Ballistic missile submarines are designed for stealth, to avoid detection at all costs. They use many sound-reducing design features, such as anechoic tiles on their hull surfaces, carefully designed propulsion systems, and machinery mounted on vibration-damping mounts.

Ballistic missile submarines equipped with nuclear warheads serve as the third leg of the nuclear triad. The invisibility and mobility of submarines offer both a reliable means of deterrence against an attack (by maintaining the threat of a second strike), and a surprise first-strike capability - particularly given the range of the weapons they carry.

Armament
The extra length and/or beam over attack subs of the same generation is in order to accommodate SLBMs such as the Russian R-29 or the NATO fielded&mdash;American manufactured Polaris-II, Poseidon and Trident-II missiles. Although some early models had to surface to launch their missiles, modern vessels typically launch while submerged at keel depths of usually less than 50 meters (164 feet). Missiles are launched upwards with an initial velocity sufficient for them to pop above the surface when their rocket motors fire, beginning the characteristic parabolic climb-from-launch of a ballistic missile.

Terminology
SSBN is the US Navy hull classification symbol for a nuclear-powered, ballistic missile-carrying submarine. The SS denotes "Submarine", the B denotes "ballistic missile," and the N denotes "nuclear powered."

In US naval slang, ballistic missile submarines are called boomers. In Britain, they are known as bombers. In both cases, submarines operate on a two-crew concept, with two complete crews including two captains, called Gold and Blue in US, Starboard and Port in UK.

The French Navy commissioned her first ballistic missile submarines as SNLE, for Sous-marin Nucléaire Lanceur d'Engin (lit. "nuclear-powered device-launching submarines"). The term applies both to ballistic missile submarines in general (for instance "British SNLE" occurs ) and, more technically, as a specific classification of the Redoutable class. The more recent Triomphant class is referred to as SNLE-NG (Nouvelle Génération, "New Generation"). The two crews used to maximise the availability time of the ships are called 'blue' and 'red' crews.

The Soviets called this type of ship RPKSN (lit. "Strategic Purpose Underwater Missile Cruiser"). This designation was applied to the Typhoon class. Another designation used was PLARB(«ПЛАРБ» - подводная лодка атомная с баллистическими ракетами, which translates as "Nuclear Submarine with Ballistic Missiles"). This designation was applied to smaller submarines such as the Delta Class. After a peak in 1984 (following Able Archer 83), Russian SSBN deterrence patrols have declined to the point where there is less than one patrol per sub each year and at best one sub on patrol at any time. Hence the Russians do not use multiple crews per ship.

Active classes

 * 🇫🇷 France
 * Le Triomphant class
 * People's Republic of China
 * Type 092
 * Type 094
 * 🇷🇺 '''Russia
 * Borei class 1 active, 2 are in trials 7 under development in Sevmash.
 * Typhoon class
 * Delta III and Delta IV classes
 * 🇬🇧 United Kingdom
 * Vanguard-class submarine
 * United States

Classes under development

 * 🇨🇳 People's Republic of China
 * Type 096 submarine


 * 🇮🇳 India
 * Arihant class submarine 1 in sea trial 2nd to launch in 2013 total 4 to be constructed.


 * 🇷🇺 Russia
 * Borei class submarine 1 active, 2 are in trials 7 under development in Sevmash.


 * 🇬🇧 United Kingdom
 * Vanguard-class replacement


 * United States
 * SSBN-X future follow-on submarine

Retired classes

 * France
 * Redoutable class
 * / Soviet Union / Russia
 * Zulu IV class (diesel powered)
 * Golf I class (diesel powered)
 * Golf II class (diesel powered)
 * Hotel I class
 * Hotel II class
 * Yankee class
 * Yankee II class
 * Delta I class
 * Delta II class
 * 🇬🇧 United Kingdom
 * Resolution-class submarine
 * United States
 * George Washington-class submarine
 * Ethan Allen-class submarine
 * Lafayette-class submarine
 * James Madison-class submarine
 * Benjamin Franklin-class submarine
 * These five classes are collectively referred to as "41 for Freedom".

Accidents
On 4 February 2009, the British HMS Vanguard (S28)  and the French Le Triomphant collided in the Atlantic. Vanguard returned to Faslane in Scotland, under her own power, and Triomphant to Île Longue in Brittany.