The Ohio class of nuclear-powered submarines includes the United States Navy's 14 ballistic missile submarines (SSBNs) and its four cruise missile submarines (SSGNs). Each displacing 18,750 tons submerged, the Ohio-class boats are the largest submarines ever built for the U.S. Navy. They are also the third-largest submarines ever built, behind the Russian Navy's Soviet era 48,000-ton Typhoon class, the last of which was retired in 2023, and 24,000-ton Borei class. Capable of carrying 24 Trident II missiles apiece, the Ohio class are equipped with just as many missiles as, if not more than, either the Borei class (16) or the deactivated Typhoon class (20).
The Resolution class was a class of four nuclear ballistic missile submarines (SSBN) built for the Royal Navy as part of the UK Polaris programme. Each submarine was armed with up to 16 UGM-27 Polaris A-3 nuclear missiles.
The Trident missile is a submarine-launched ballistic missile (SLBM) equipped with multiple independently targetable reentry vehicles (MIRV). Originally developed by Lockheed Missiles and Space Corporation, the missile is armed with thermonuclear warheads and is launched from nuclear-powered ballistic missile submarines (SSBNs). Trident missiles are carried by twelve United States Navy Ohio-class submarines, with American warheads, as well as four Royal Navy Vanguard-class submarines, with British warheads. The missile is named after the mythological trident of Neptune.
A submarine-launched ballistic missile (SLBM) is a ballistic missile capable of being launched from submarines. Modern variants usually deliver multiple independently targetable reentry vehicles (MIRVs), each of which carries a nuclear warhead and allows a single launched missile to strike several targets. Submarine-launched ballistic missiles operate in a different way from submarine-launched cruise missiles.
The Vanguard class is a class of nuclear-powered ballistic missile submarines (SSBNs) in service with the Royal Navy. The class was introduced in 1994 as part of the Trident nuclear programme, and comprises four vessels: Vanguard, Victorious, Vigilant and Vengeance, built between 1986 and 1999 at Barrow-in-Furness by Vickers Shipbuilding and Engineering, now owned by BAE Systems. All four boats are based at HM Naval Base Clyde , 40 km (25 mi) west of Glasgow, Scotland.
USS Patrick Henry (SSBN-599), named after the American Revolutionary War figure and Founding Father Patrick Henry (1736–1799), was a George Washington class nuclear-powered fleet ballistic missile submarine of the United States Navy. She was later converted into an attack submarine and redesignated SSN-599.
A ballistic missile submarine is a submarine capable of deploying submarine-launched ballistic missiles (SLBMs) with nuclear warheads. These submarines became a major weapon system in the Cold War because of their nuclear deterrence capability. They can fire missiles thousands of kilometers from their targets, and acoustic quieting makes them difficult to detect, thus making them a survivable deterrent in the event of a first strike and a key element of the mutual assured destruction policy of nuclear deterrence. The deployment of ballistic missile submarines is dominated by the United States and Russia. In fact, 70 % of nuclear warheads in the USA are carried by SSBN submarines.
HMS Resolution (S22) was the first of the Royal Navy's Resolution-class ballistic missile submarines. She operated from 1968 until 1994 providing the UK Polaris at sea nuclear deterrent.
USS Alabama (SSBN-731) is the sixth Ohio-class nuclear-powered ballistic missile submarine, and the seventh United States vessel to be named for the state of Alabama. The boat's motto duplicates the state's motto, Audemus Jura Nostra Defendere.
The UGM-133A Trident II, or Trident D5 is a submarine-launched ballistic missile (SLBM), built by Lockheed Martin Space in Sunnyvale, California, and deployed with the United States and Royal Navy. It was first deployed in March 1990, and remains in service. The Trident II Strategic Weapons System is an improved SLBM with greater accuracy, payload, and range than the earlier Trident C-4. It is a key element of the U.S. strategic nuclear triad and strengthens U.S. strategic deterrence. The Trident II is considered to be a durable sea-based system capable of engaging many targets. It has payload flexibility that can accommodate various treaty requirements, such as New START. The Trident II's increased payload allows nuclear deterrence to be accomplished with fewer submarines, and its high accuracy—approaching that of land-based missiles—enables it to be used as a first strike weapon.
The eleventh HMS Vanguard of the Royal Navy is the lead boat of her class of Trident ballistic missile-armed submarines. The submarine is based at Faslane, HMNB Clyde, Argyll, Scotland.
USS Casimir Pulaski (SSBN-633), a James Madison-class ballistic missile submarine, was the second ship of the United States Navy to be named for Casimir Pulaski (1745–1779), a Polish general who served in the American Revolutionary War.
USS Von Steuben (SSBN-632), a James Madison-class fleet ballistic missile submarine, was the second ship of the United States Navy to be named for Baron Friedrich Wilhelm von Steuben (1730–1794), a Prussian army officer who served in the American Revolutionary War.
His Majesty's Naval Base, Clyde, primarily sited at Faslane on the Gare Loch, is one of three operating bases in the United Kingdom for the Royal Navy. It is the navy's headquarters in Scotland and is best known as the home of Britain's nuclear weapons, in the form of nuclear submarines armed with Trident missiles.
HMSVigilant is the third Vanguard-class submarine of the Royal Navy. Vigilant carries the Trident ballistic missile, the United Kingdom's nuclear deterrent.
HMS Vengeance is the fourth and final Vanguard-class submarine of the Royal Navy. Vengeance carries the Trident ballistic missile, the UK's nuclear deterrent.
The Royal Navy Submarine Service is one of the five fighting arms of the Royal Navy. It is sometimes known as the Silent Service, as submarines are generally required to operate undetected.
The Dreadnought class is the future replacement for the Royal Navy's Vanguard class of ballistic missile submarines. Like their predecessors they will carry Trident II D-5 missiles. The Vanguard submarines entered service in the United Kingdom in the 1990s with an intended service life of 25 years. Their replacement is necessary for maintaining a continuous at-sea deterrent (CASD), the principle of operation behind the Trident system.
Trident, also known as the Trident nuclear programme or Trident nuclear deterrent, covers the development, procurement and operation of nuclear weapons in the United Kingdom and their means of delivery. Its purpose as stated by the Ministry of Defence is to "deter the most extreme threats to our national security and way of life, which cannot be done by other means". Trident is an operational system of four Vanguard-class submarines armed with Trident II D-5 ballistic missiles, able to deliver thermonuclear warheads from multiple independently targetable re-entry vehicles (MIRVs). It is operated by the Royal Navy and based at Clyde Naval Base on the west coast of Scotland. At least one submarine is always on patrol to provide a continuous at-sea capability. The missiles are manufactured in the United States, while the warheads are British.
Vice-Admiral Sir Arthur Richard Hezlet, nicknamed Baldy Hezlet, was a decorated Royal Navy submariner. He became the Royal Navy's youngest captain at the time – aged 36 – and its youngest admiral, aged 45. In retirement he became a military historian.
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