Duchess meets submarine families

The Duchess of Cornwall toured the nuclear submarine

The Duchess of Cornwall has visited the Royal Navy's newest nuclear submarine, under construction in Cumbria.

The Duchess launched HMS Astute in 2007 and returned to visit crew and their families at the BAE Systems shipyard in Barrow-in-Furness on Tuesday.

She became the first member of the Royal Family to step on board when she was given a private tour.

HMS Astute is the first submarine built in the UK since HMS Vengeance, which was launched in 1998.

Intelligence gathering

The 7,800 tonne vessel is one of four nuclear-powered submarines being built at the BAE Systems shipyard.

Each of the four submarines will be almost 100m (328ft) long.

The other three vessels are called HMS Audacious, Ambush and Artful.

They will support the Vanguard Class submarines - whose Trident nuclear missiles carry Britain's nuclear deterrent - as well as gathering intelligence.

Their nuclear reactors mean they will not need refuelling once in their 25-year-life and they make their own air and water.

The government signed the Astute contract in 1997 but the first hull sections were not laid until 2001.

HMS Astute is due to enter service in 2009.