Astute class submarine

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HMS Astute on the shiplift after rollout
Class overview
Builders:	BAE Systems Submarine Solutions
Operators:	Royal Navy
Preceded by:	Trafalgar class
Building:	4: Astute, Ambush, Artful, Audacious
Planned:	7[1]
Completed:	0
General characteristics
Displacement:	7,800 tonnes submerged
Length:	97 m (323 ft)
Beam:	11.3 m (37 ft)
Draught:	10 m (33 ft)
Propulsion:	Rolls-Royce PWR2 reactor (with full submarine life core), MAN (Paxman) 1900 kilowatt diesel generator
Speed:	29 knots (54 km/h) submerged
Range:	Limited only by food supplies and maintenance requirements.
Test depth:	300 m
Complement:	98 officers and men (full capacity of 109)
Sensors and processing systems:	Thales Underwater Systems Sonar 2076 Atlas Hydrographic DESO 25 depth-finding echosounder 2 x Thales Optronics CM010 periscopes Raytheon Systems Ltd Successor IFF system
Armament:	6 × 21 inch (533 mm) torpedo tubes, 38 Spearfish torpedoes, UGM-84 Harpoon and Tomahawk Block III cruise missiles; naval mines

The Astute class submarines are the next generation nuclear fleet submarines of the Royal Navy. When completed, the boats will set a new standard for the Royal Navy in terms of weapons load, improved communications facilities, stealth and comfort for the crew. Lord Drayson (Former Minister for Defence Equipment and Support) said, "These submarines are hugely impressive vessels, and will provide the Royal Navy with a world class capability." The boats are being constructed by BAE Systems Submarine Solutions at Barrow-in-Furness.

Contents 1 Background 2 History 2.1 Contract award 2.2 Delays 2.3 Further orders 3 Sensors 4 Boats 5 General characteristics 6 External links 7 References

[edit] Background

As the Swiftsure-class submarines aged, the Royal Navy began to design their replacements. The original design called for large submarines designed for blue-water operations. Feasibility studies began in 1986 and were completed by 1989. A design contract was placed with Vickers Shipbuilding and Engineering Ltd. (VSEL) in 1987, but with the end of the Cold War the project was cancelled in 1992. Emphasis switched to the production of a second batch of Trafalgar-class submarines (Batch 2 Trafalgar Class or B2TC). However the development was extremely slow and initial tenders received from VSEL in June 1995 were too expensive.

Meanwhile, 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." The proposed replacement boats were redesigned; the primary mission of the Astute class became direct support of surface forces.

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 will be entirely decommissioned by 2010, when only the first of the Astute-class will be coming into service. HMS Trafalgar is to be decommissioned in 2008, followed by HMS Turbulent in 2011.

[edit] History

[edit] Contract award

On March 17, 1997, The Ministry of Defence announced that it would place a £2 billion order for three submarines and further that they would be called the Astute class. On March 26, 1997, the contract was signed with GEC-Marconi Limited 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 Submarines).

Astute-class boats will be powered by a Rolls-Royce PWR2 (Core H) reactor and fitted with a pump-jet propulsor. The PWR2 reactor was developed for Vanguard-class ballistic missile submarines. As a result Astute-class boats are about 30 per cent larger than previous British attack submarines, which were powered by smaller reactors. It will be 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.

Like all Royal Navy submarines, the fin of the Astute-class boats will be reinforced to allow surfacing through ice caps. They can fire Tomahawk cruise missiles from their launch tubes, including the new "tactical Tomahawk" currently under development. More than 39,000 acoustic tiles will mask the vessel's sonar signature, giving the Astute class a better stealth quality than any other submarine previously operated by the Royal Navy. The vessel is equipped with the advanced 2076 Sonar System, which is capable of identifying and tracking vessels across thousands of square miles of ocean. The Royal Navy describes Sonar 2076 as the most advanced Sonar in service with any Navy in the World. According to the MOD around 5,500 people are presently employed in the Astute building programme.

[edit] Delays

The Astute class was expected to be built roughly 20% quicker than earlier boats, with lower running costs and a much smaller ship’s company. However, the programme's progress has slipped by 4 years and has a predicted cost overrun of £1 billion,^[2] and required a U.S. engineering management team from General Dynamics Electric Boat to be brought in to resolve programme problems,^[3] backed up by design and production drawing work carried out in the U.S. between 2004 and 2007 under a U.S. Navy contract.^[4] The UK House of Commons Defence Committee, in July 2004, estimated the cost of Astute as £3,500 million compared to £2,600 million approved at Main Gate.^[5] Furthermore they noted that the predicted in-service date was January 2009 compared to the date of June 2005 approved at Main Gate. A £164 million cost increase was disclosed in a National Audit Office report in November 2006. However the NAO noted the in-service date was then ahead of schedule compared to the revised in-service date.^[6]

BAE Systems has indicated that the Astute submarine project has maintained its improved performance, and first-of-class HMS Astute was launched by Camilla, The Duchess of Cornwall on 8 June 2007.^[7] Work on the second submarine, Ambush, is also proceeding well with major milestones such as the closure of the reactor compartment, demonstrating significant schedule advance compared with Astute. BAE and the MoD have made efforts to reduce costs and achieved significant cost-cutting and productivity gains.^[6]

[edit] Further orders

As of 28 August 2006 BAE was negotiating for a contract to build another four Astute class submarines.^[8] The then Armed Forces Minister, Adam Ingram, has announced a further advance in the Astute Class submarine programme, with preparations for a further SSN underway. The Minister told MPs: "We are working with industry as part of the Defence Industrial Strategy to achieve an affordable and sustainable submarine programme. In support of this we have ordered long-lead items for Boat Four." BAE Systems Submarines had ordered long-lead items for a fourth boat in August 2006. In March 2007, DefenseNews.com reported that a final price for boats 2 & 3 had been reached.^[9] The fourth boat was ordered on 21 May 2007 and it was announced that she is to be called Audacious. It has also been proposed that the future replacement of the Vanguard Class SSBN be based on a stretched version of the Astute class. ^[10]

The Guardian reported in January 2008 that proposals for budget cuts to the UK armed forces could restrict the Astute Class to just the first four boats, with all further orders being cancelled,^[11] though long-lead items have been purchased for further boats.

[edit] Sensors

The Astute Combat Management System (ACMS) is an evolved version of the Submarine Command System (SMCS) used on other classes of submarine. The system will receives data from the boat's sensors and displays real time imagery on all command consoles. Sensors include the Type 2076 integrated passive / active search and attack sonar suite with bow, intercept, flank and towed arrays; a DESO 25 high-precision echosounder; two CM010 non-hull-penetrating optronic masts which carry thermal imaging, low light TV and colour CCD TV sensors.

[edit] Boats

Name	Pennant number	Laid down	Launched	Commissioned
Astute	S119	31 January 2001	8 June 2007[12]	2009
Ambush	S120	22 October 2003	?	2010
Artful	S121	11 March 2005	?	2012
Audacious	S122	Late 2007	?	?
[A-05]	S123	Planned	?	?
[A-06]	S124	Planned	?	?
[A-07]	S125	Planned	?	?
[A-08]	?	Subject to cost [13]	?	?

[edit] General characteristics

• Sensors:
  • Thales Underwater Systems Sonar 2076
  • Atlas Hydrographic DESO 25 depth-finding echosounder
  • Two Thales Optronics CM010 periscopes
  • Raytheon Systems Ltd Successor IFF system

[edit] External links

• Royal Navy official site
• Photos from the roll out / launch (BBC)
• ThisIsLondon article "Britain launches massive submarine that can hear a ship from across the Atlantic" (June 8th, 2007)
• Navy Matters - Astute Class
• BAE Systems: Murray Easton Interview

[edit] References

v • d • e Astute-class submarine Astute | Ambush | Artful | Audacious List of submarines of the Royal Navy List of submarine classes of the Royal Navy

v • d • e Current & future SSN classes  Rubis; Barracuda ·  Victor III, Sierra I & II, Akula; Graney ·  Los Angeles, Seawolf, Virginia ·  Swiftsure, Trafalgar; Astute ·  Type 091, Type 093

v • d • e Groundbreaking submarines Drebbel's submarine (1620) · Turtle (1775) · Brandtaucher (1850) · H.L. Hunley (1863) · Plongeur (1863) · Ictineo II (1864) · Flach (1863) · Submarino Peral (1888) · Gymnote (1888) · USS Holland (1897) · German Type XXI submarine (1943) · USS Albacore (1953) · USS Nautilus (1954) · Zulu class SSB (1955) · USS Halibut (1960) · USS Narwhal (1967) · Alfa-class SSN (1977) · Gotland class submarine (1992) · Type 212 submarine (2005) · Astute class submarine (2007)