Her nuclear-powered engine will propel her through the water at more than 20 knots, yet the UK’s first stealth sub makes less noise than a baby dolphin, making her as good as undetectable by enemy ships.
Astute’s sonar is so advanced that if she was lying in the English Channel she would be able to detect ships leaving New York harbour 3,000 nautical miles away (although the details of how she can do this are classified).
The nuclear reactor will never need refuelling, and with an ability to make oxygen and drinking water out of sea water, the sub could stay underwater for its entire 25-year lifespan were it not for the needs of the crew.
Once she goes into operation in 2009, Astute will carry a 98-man crew and stay at sea for 12 weeks on a routine patrol.
She will carry 38 Tomahawk cruise missiles, with a range of 1,240 miles, meaning Astute could attack targets in North Africa with pinpoint accuracy while sitting off the coast of Plymouth.