The Progress on the Royal Navy's Ballistic Missile Submarine Replacement Program

With the U.K.’s status as a sovereign country assured, and with the major political parties in London committed to retaining an independent nuclear deterrent, the big question now is, what will replace the four Vanguard-class boats when they begin to retire from service in or around 2028?

Commissioned into service between 1993 and 1999, HMS Vanguard, Victorious, Vigilant, and Vengeance were originally designed for a 25-year lifespan; however, this has been extended by up to 13 years, postponing the requirement for a new class of SSBN and bringing the procurement timeframe into line with the Ohio-class replacement program (the oldest U.S. boomer, USS Henry M. Jackson, is scheduled to leave service in 2027).

Concept work on Britain’s so-called Successor SSBN began in 2007, with the Ministry of Defense appointing an industry team consisting of shipbuilder and design lead BAE Systems plus Babcock (providing the torpedo handling/launch system, signal ejector system, and through-life support expertise) and Rolls-Royce (responsible for the nuclear steam-raising plant). The MOD approved the “initial gate” business case for the new submarines in 2011, releasing funds for a five-year assessment phase intended to bring the design to 70 percent maturity.

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