This past spring the United Kingdom commissioned its third Astute -class nuclear-powered attack submarine into service. HMS Artful was built by BAE Systems, launched in May 2014, and has now joined the fleet at naval base Clyde in Faslane, Scotland. A total of seven Astute -class SSNs are eventually planned for Royal Navy service by the mid-2020s. The Artful ’s sisters include first-in-class HMS Astute and second unit HMS Ambush , which entered service in 2010 and 2013 respectively. Future members of the class are to bear the names Agamemnon , Anson , and Audacious , while the name of the seventh and final submarine has not yet been selected. The Astute -class boats are armed with a mix of Spearfish heavyweight torpedoes and Tomahawk land-attack missiles. The 318-foot attack submarines each have a top speed of 30 knots, displace 7,400 tons when submerged, and carry a crew of roughly 100 personnel.