Vanguard Class Submarine - Design

Design

The Vanguard class were designed and built at Barrow-in-Furness by Vickers Shipbuilding and Engineering, now BAE Systems Submarine Solutions. The Devonshire Dock Hall was built specifically for the construction of the submarines. The missile compartment is based on the system used on the American Ohio class, although only 16 missiles are fitted, rather than the 24 equipped on the Ohio class.

The Vanguard submarines were designed from the outset as nuclear-powered ballistic missile platforms to accommodate the Trident D-5 submarine-launched ballistic missile. This required the boats to be significantly larger than the previous Polaris missile equipped Resolution class, and they are some of the largest submarines ever built, only eclipsed by the American Ohio-class, and Russian Typhoon- and Borei-class submarines.

In addition to the missile tubes, the submarines are fitted with four 21 inch (533 mm) torpedo tubes and carry the Spearfish heavyweight torpedo allowing them to engage submerged or surface targets at ranges up to 65 kilometres (40 mi; 35 nmi). Two SSE Mark 10 launchers are also fitted allowing the boats to deploy Type 2066 and Type 2071 decoys, and a UAP Mark 3 electronic support measures (ESM) intercept system is carried. A 'Core H' reactor is fitted to each of the boats during their long-overhaul refit periods, ensuring that none of the submarines will require further re-fuelling for the rest of their service lives.

The boats are capable of deploying with a maximum of 192 independently targetable warheads, or MIRVs, with immediate readiness to fire. However, as a result of a decision taken by the 1998 Strategic Defence Review this was reduced to 48 warheads with a readiness to fire reduced 'to days rather than minutes'. Furthermore the total number of warheads maintained by the United Kingdom was reduced to approximately 200, with a total of 58 trident missiles. The reduced warhead load per missile allowed the development of lower-yield non-strategic warheads loading options. The 2010 Strategic Defence and Security Review reduced this number further and the submarines will put to sea in future with a reduced total of 40 warheads and a reduced missile load of 8 (from a maximum possible 16). The number of operationally available nuclear warheads is to be reduced 'from fewer than 160 to no more than 120' and the total UK nuclear weapon stockpile will number no more than 180.

HMS Vanguard, Victorious, Vigilant and Vengeance were commissioned in 1993, 1995, 1996 and 1999 respectively.