Vanguard-class submarine

The Vanguard class is a group of four nuclear-powered ballistic missile submarines (SSBNs) used by the Royal Navy.

These massive vessels serve as the United Kingdom's sole platform for its nuclear weapons. This role is known as a nuclear deterrent, which is meant to prevent conflict. The class includes four specific ships: HMS Vanguard, HMS Victorious, HMS altogether, and HMS Vengeance. They are based at HM Naval Base Clyde, located west of Glasgow, Scotland. These submarines are scheduled to be replaced by the Dreadnought class starting in the early 2030s.

Each submarine operates using a specialized propulsion system. They use the Rolls-Royce PWR 2, which is a pressurized water reactor. This reactor generates heat to produce steam. This steam drives two GEC steam turbines. These turbines are linked to a single shaft pump jet propulsor. This setup allows the submarines to reach submerged speeds of over 25 knots. The system is incredibly efficient for long-distance travel. It is estimated that one submarine could circumnavigate the entire world 40 times without needing to refuel. During long-overhaul refit periods, a 'Core H' reactor is installed. This ensures the boats never require further refueling for the rest of their service lives.

The submarines are designed to carry a significant amount of weaponry. They feature 16 ballistic missile tubes. However, following a 2010 Strategic Defence and Security Review, the Royal Navy typically loads only eight of these tubes with UGM-133 Trident II missiles. These missiles can carry nuclear warheads, which are known as Holbrook warheads. These warheads use a Mark 4A aeroshell and have a yield of 100kt. While the boats are capable of deploying up to 192 independently targetable warheads (MIRVs), current operational levels are much lower. The submarines also carry four 21-inch torpedo tubes. These are used to deploy Spearfish heavyweight torpedoes against submerged or surface targets.

To navigate and detect objects, the class uses advanced sensory technology. They utilize the Thales Underwater Systems Type 2054 composite sonar. This is a multi-mode system that includes the 2046, 2043, and 2082 sonars. The Type 2043 is a hull-mounted active and passive search sonar. The Type 2082 acts as a passive intercept and ranging sonar. Additionally, a Type 2046 towed array sonar provides low-frequency passive search capabilities. For looking above the water, the boats carry two periscopes. These are the CK51 search model and the CH91 attack model. Both models include thermal imaging cameras and conventional optics to assist the crew.

The history of the Vanguard class began with the need to replace older vessels. In the late 1960s, the UK operated four Resolution-class submarines using US-built Polaris missiles. By the early 1980s, the government needed a replacement. On 24 January 1980, the House of Commons voted 308 to 52 to keep an independent nuclear deterrent. After examining several options, the UGM-96 Trident I was the favorite. However, the US accelerated the development of the improved Trident II system. In 1982, Prime Minister Margaret Thatcher requested the Trident II system. This led to an agreement where Britain made a 5% research and development contribution.

The construction of these submarines was a massive engineering undertaking. The Ministry of Defence designed the class in the early 1980s. Vickers Shipbuilding and Engineering (VSEL) handled the detailed design at Barrow-in-Furness. Because the submarines were so large, a special facility was required. Engineers built the Devonshire Dock Hall specifically for this purpose between 1982 and 1986. Margaret Thatcher laid the keel for the first boat, HMS Vanguard, on 3 September 1986. The first vessel was launched in 1992 and commissioned in 1993. The final boat, HMS Vengeance, was commissioned in 1999.

Significant investments were made to support the entire program. Extensive redevelopment occurred at HMNB Clyde and the Royal Naval Armaments Depot Coulport. Rosyth dockyard also underwent major changes. These upgrades included improved facilities for handling, storage, and engineering. The estimated cost for these redevelopments was £550 million. Looking toward the future, the government is preparing for the Dreadnought class. This new class will use a new PWR3 nuclear reactor. The Ministry of Defence estimates the cost for the replacement program at £31 billion. This includes a £10 billion contingency fund over a 35-year period. The new fleet is expected to begin operations by the 2030s.