Ambush, the second of the Royal Navy's Astute Class attack submarines, is today preparing to leave her builder's yard to begin sea trials.
In the next few days, the 7,400-tonne submarine will leave the BAE Systems shipyard in Barrow-in-Furness in Cumbria, where she was built, and sail to Her Majesty's Naval Base Clyde in Scotland.
The seven Astute Class boats planned for the Royal Navy are the most advanced and powerful attack submarines Britain has ever sent to sea.
They feature the latest nuclear-powered technology, which means they never need to be refuelled and can circumnavigate the world submerged, manufacturing the crew's oxygen from seawater as they go.
Minister for Defence Equipment, Support and Technology Philip Dunne said after viewing the submarine, touring the shipyard and meeting the workforce:
"This is my first visit to one of the UK's most advanced defence industries, and I am hugely impressed with what I have seen at Barrow-in-Furness. Ambush is a very sophisticated and potent vessel and I look forward to her departure from the shipyard here for the sea trials that will prepare her for her planned entry into service with the Royal Navy next year.
"Ambush and her sisters are the most powerful and advanced attack submarines ever ordered for the Royal Navy; they are needed by the fleet and they will play a vital role in the future defence of the UK.
"The completion of Ambush is a tribute to the hard work and commitment of the thousands of people employed in this country's world-class submarine industry."
The Astute Class is quieter than older submarines and has the ability to operate covertly and remain undetected in almost all circumstances despite being 50 per cent bigger than the Royal Navy's current Trafalgar Class submarines.
The boat's Commanding Officer, Commander Peter Green, said:
"We are grateful to all the people who have worked hard to construct this vessel. The crew cannot wait to start sea trials and take this magnificent vessel a step closer to beginning operations.
"It is now time to start putting Ambush through her paces on sea trials and prove that this amazing piece of equipment is ready for operations."