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Defence & space
Defence & spaceNaval - Ballistic Missile Submarine (SSBN)

Dreadnought Class Submarine Programme (Vanguard Class Successor)

Barrow-in-Furness, UK (construction) · 2016 (construction started) - 2030s (first boat expected in service) · £31 billion (estimated programme cost), with a £10 billion contingency fund.

The judgement call

Account-gated at launch

The Dreadnought class is the future replacement for the Vanguard class, designed to maintain the UK's Continuous At-Sea Deterrent (CASD). - The programme is one of the most complex engineering projects in the UK, requiring significant investment and long-term planning. - Collaboration with the US on the Trident II D5 Life Extension programme ensures the missile system remains viable for the Dreadnought class.

Key engineering challenges

Designing and constructing a new class of highly complex nuclear-powered ballistic missile submarines. - Integrating the Trident II D5 missile system and its associated launch infrastructure. - Ensuring extreme stealth capabilities and survivability for continuous at-sea deterrence. - Managing the immense scale and technical challenges of building the largest submarines in Royal Navy history.

Project facts

Client / owner
Royal Navy / UK Ministry of Defence
Lead contractor
BAE Systems Submarines
Lead designers
BAE Systems Submarines
Project type
new build
Scale
Four new SSBNs; will be the largest and most powerful submarines ever operated by the Royal Navy; each will carry Trident II D5 ballistic missiles.
Disciplines
Naval architecture; nuclear engineering; mechanical engineering; electrical engineering; systems integration; stealth technology
Standards & frameworks
Naval nuclear safety standards; UK defence procurement standards.

Sources: Wikipedia: Dreadnought-class submarine (https://en.wikipedia.org/wiki/Dreadnought-class_submarine) - Parliament.uk: Replacing the UK's Nuclear Deterrent: Progress of the Dreadnought... (https://commonslibrary.parliament.uk/research-briefings/cbp-8010/) - BAE Systems: Dreadnought (https://www.baesystems.com/en/product/dreadnought) - 19FortyFive: New U.S. Columbia-Class and UK Dreadnought Submarines Share... (https://www.19fortyfive.com/2026/03/new-u-s-columbia-class-and-uk-dreadnought-submarines-share-the-same-world-war-iii-nuclear-missiles/)