Audacious is the fourth of the seven Astute Class submarines being built for the Royal Navy.

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On paper, at least, the Astute class is a significant step forward.

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The ongoing revamp is timed to coincide with the arrival in 2009 of the new Astute class of hunter killer submarines, currently being built at Barrow-in-Furness in Cumbria.

BBC: NEWS | UK | Scotland | Glasgow and West | Sailors move in to ?125m quarters

William and Catherine, who are known as the Earl and Countess of Strathearn in Scotland, were due to travel to Barrow-in-Furness, Cumbria, to learn about the new Astute Class of nuclear powered submarines being built for the Royal Navy by BAE Systems.

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Further write-offs loom over two contracts, for Nimrod marine-surveillance aircraft and new Astute-class nuclear submarines.

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