Astute - class submarine The " Astute " class is the latest class of nuclear - powered fleet submarine s in service with the British Royal Navy . The class sets a new standard for the Royal Navy in terms of weapons load , communication facilities and stealth . The boats are being constructed by BAE Systems Submarine Solutions at Barrow - in - Furness . Seven boats will be constructed . The first of class , " Astute " , was launched in 2007 and commissioned in 2010 , and the second , " Ambush " , was launched on 6 January 2011 , and commissioned on 1 March 2013 . Development . The Royal Navy has changed its submarine - employment strategy from the Cold War emphasis on anti - submarine warfare to the concept of " Maritime Contributions to Joint Operations . " Approval for studies to define the " Batch 2 " Trafalgar " class " ( what would become the " Astute " class ) was given in June 1991 . In July 1994 risk reduction studies were authorised in parallel with the formal bid phase of the project . On 17 March 1997 , the Ministry of Defence announced that it would place a £2 billion order for three submarines and that they would be called the " Astute " class . On 26 March 1997 the contract was signed with GEC - Marconi for the first three boats : " Astute " , " Ambush " and " Artful " . These names were last given to " Amphion " - class submarines that entered service towards the end of World War II . GEC would build the submarines at its VSEL subsidiary ( now BAE Systems Submarine Solutions ) . Original plans were for seven boats of the " Astute " class to replace five " Swiftsure " - class submarines ( " Sovereign " , " Superb " , " Sceptre " , " Spartan " , and " Splendid " ) and the two oldest " Trafalgar " - class boats ( " Trafalgar " and " Turbulent " ) . The " Swiftsure " class entered service between 1973 and 1977 and were entirely decommissioned by 2010 , when only the first of the " Astute " class was coming into service . " Trafalgar " was decommissioned in December 2009 , to be followed by " Turbulent " in 2011 . An estimated 5 , 900 people are employed directly as a result of the project ; 3 , 500 BAE Systems staff at Barrow and 2 , 400 other people around the UK . As of August 2006 BAE Systems was negotiating for a contract to build another four " Astute " - class submarines ( hulls four to seven ) . The fourth boat was ordered on 21 May 2007 , to be called " Audacious " , and the names of the other hulls have been agreed as " Agamemnon " , " Anson " , and " Ajax " . On 15 September 2011 it was announced that hull 5 would now be named " Anson " . Upon the beginning of sea trials of " Astute " in November 2009 , it was reported that long - lead items for hulls five and six have been ordered , including their nuclear reactor cores , and that the stated intention of the MoD was for a total of seven " Astute " - class submarines . On 25 March 2010 , BAE Systems were given the go - ahead by the government to begin construction on hulls 5 and 6 , being given a £300 million contract for the " initial build " of hull five and " long lead procurement activities " for boat six . In the same week the government re - affirmed their commitment to the construction of seven " Astute " - class submarines . Work on the second and third submarines , " Ambush " and " Artful " , proceeded well with major milestones such as the closure of " Ambush " s reactor compartment , demonstrating significant schedule advance compared with " Astute " . BAE Systems and the MoD have made efforts to reduce costs and achieved significant cost - cutting and productivity gains . A £580 million cost increase was agreed in 2007 due to maturing of the design requiring more materials , inflationary costs , and " some programme throughput assumptions at the Barrow site not being borne out . " First - of - class HMS " Astute " was launched by Camilla , Duchess of Cornwall on 8 June 2007 . The order of seven " Astute " - class boats was confirmed in the Strategic Defence and Security Review of October 2010 . In December that year it was confirmed by the MoD that " early work " was under way on boats five and six . On 13 October 2011 , the fifth boat , " Anson " , was laid down at Devonshire Dock Hall and is now under construction like boats three and four . On 10 December 2012 the MOD awarded BAE a £1 . 2 billion contract for work on " Audacious " . The MOD also confirmed on the same date a further £1 . 5 billion funding for submarines " Anson " , " Agamemnon " and " Ajax " . The MOD Defence Equipment Plan 2012 refers to ' the completion of the remainder of the seven class of " Astute " attack submarines ' . Programme delays . BAE Systems issued a profit warning on 11 December 2002 as a result of the cost overruns and delays it was experiencing with the " Astute " class and also the Nimrod MRA4 maritime reconnaissance / attack aircraft . The delay was caused primarily by the problems of using 3D CAD ; Armed Forces Minister Adam Ingram said in 2006 that " due to the complexity of the programme , the benefits that CAD was envisaged to provide were more difficult to realise than either MoD or the contractor had assumed . " Other issues were the insufficient capabilities within GEC - Marconi which became evident after contract - award and poor programme management . BAE and the Ministry of Defence reached an agreement in February 2003 whereby they would invest £250 million and £430 million respectively to address the programme ' s difficulties . A major element of this was the enlisting of advice and expertise from General Dynamics Electric Boat . The MoD also signed a design and production drawing work contract through the U . S . Navy which ran from 2004 to 2007 . As of March 2008 the programme was 48 per cent ( or £1 . 2 billion ) over - budget and 47 months late . Further delays due to a range of technical and programme issues brought the programme to a position of 57 months late and 53 per cent ( or £1 . 35 billion ) over - budget by November 2009 , with a forecast cost of £3 . 9 billion for the first three " Astute " boats . In June 2012 the order was placed for the manufacture of the nuclear reactor for the seventh " Astute " - class submarine " Ajax " alongside the refurbishment of Rolls - Royce manufacturing facility in Raynesway , Derby and the development and production of the first reactor for the next generation of SSBN to replace the " Vanguard " class . Some serious quality assurance problems have been identified in the first boats built . Due to the failure of a pipe cap , made of incorrect material although construction records indicated the correct metal had been used , " Astute " was forced to surface following a leak that was flooding a compartment . Other problems have been identified , including the wrong type of lead being used in a reactor instrument , and other quality issues leading to early corrosion of components . Characteristics . The boats of the " Astute " class are powered by a Rolls - Royce PWR2 ( Core H ) ( a pressurised water ) reactor and fitted with a pump - jet propulsor . The PWR2 reactor was developed for the " Vanguard " - class ballistic missile submarines . As a result the new submarines are about 30 per cent larger than previous British fleet submarines , which were powered by smaller - diameter reactors . Like all Royal Navy submarines , the bridge fin of the " Astute " - class boats is specially reinforced to allow surfacing through ice caps . These submarines can also be fitted with a dry deck shelter , which allows special forces ( e . g . SBS ) to deploy whilst the submarine is submerged . More than 39 , 000 acoustic tiles mask the vessel ' s sonar signature , giving the " Astute " class a better stealth quality than any other submarine previously operated by the Royal Navy . Speculation released by the media stated that by using advanced stealth technology " Astute " " makes less noise than a baby dolphin , making her as good as undetectable by enemy ships . " " Astute " is the first Royal Navy submarine class to have a bunk for each member of the ship ' s company , ending the practice of ' hot bunking ' , whereby two sailors on opposite watches shared the same bunk at different times . However , they have less mess - deck space than the built 45 years earlier . The Royal Navy announced a speed of 29 + knots for the class , but it is reported this speed could not be reached in the trials of " Astute " due to a propulsion design problem . It is unclear if this problem can be overcome , and at the launch of the " Ambush " the Royal Navy only stated she was " capable of speeds in excess of 20 knots " . Weapons and systems . The " Astute " class has stowage for 38 weapons and would typically carry both Spearfish heavy torpedoes and Tomahawk Block IV cruise missiles , the latter costing £870 , 000 each . The Tomahawk missiles are capable of hitting a target to within a few metres within a range of 1 , 240 miles ( 2 , 000 km ) . The " Astute " class will also be able to fire the new " tactical Tomahawk " currently under development . The Astute Combat Management System is an evolved version of the Submarine Command System used on other classes of British submarine . The system receives data from the boat ' s sensors and displays real time imagery on all command consoles . The submarines also have Atlas Hydrographic DESO 25 high - precision echosounders , two CM010 non - hull - penetrating optronic masts — in place of conventional periscope s — which carry thermal imaging and low - light TV and colour CCD TV sensors . The class also mounts a Raytheon Successor IFF system . For detecting enemy ships and submarines the " Astute " class are equipped with the sophisticated Thales Underwater Systems Sonar 2076 , an integrated passive / active search and attack sonar suite with bow , intercept , flank and towed arrays . BAE claims that the 2076 represents a " step change " over previous sonars and is the world ' s most advanced and effective sonar system . In 2012 , during simulated battles with the United States Navy ' s latest ( the USS " New Mexico " ) , it was reported that the Americans were " taken aback " by " Astute " ' s capabilities . Royal Navy Commander Ian Breckenridge was quoted saying : “ Our sonar is fantastic and I have never before experienced holding a submarine at the range we were holding USS " New Mexico " . The Americans were utterly taken aback , blown away with what they were seeing . ” Boats of the class . Some aspects of the later " Astute " - class submarines will be different from boats 1 - 3 , mostly related to the combat system — primarily the command , navigation and sonar systems . " Audacious " is the first Royal Navy submarine to use a shared computer environment for the different systems , common consoles and cabinets , and commercial " off - the - shelf " hardware and software , to reduce costs and improve maintainability . These changes have been back - fitted to boat 3 , " Artful " ; the eventual aim is to back - fit the " Common Combat System " to " Astute " and " Ambush " , and progressively to the rest of the Royal Navy submarine fleet .