The Royal UK Navy’s stealthiest nuclear-powered attack submarine HMS Astute is preparing for extensive sea trials.

The 7,800t submarine built by BAE Systems is undergoing final test and commissioning before leaving the company’s shipyard in Barrow-in-Furness for sea trials, prior to entering service with the navy.

The 97m-long HMS Astute can move at a submerged speed of 54km/h with a crew of 98. It is powered by a nuclear reactor that will allow the submarine to operate for 25 years without refuelling, and allows for patrols of up to 90 days submerged and undetected.

The submarine carries heavyweight Spearfish torpedoes and Tomahawk land-attack missiles. The Astute is also well equipped with the latest stealth technology to avoid detection and the advanced Sonar 2076 system to locate and identify other vessels.

When commissioned, the submarine will undertake a variety of missions including anti-ship and anti-submarine action, intelligence gathering and support for land forces.