BAE officially names second Astute class submarine

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Yesterday saw the official naming of HMS Ambush, the second of seven Astute class hunter-killer submarines being built for the Royal Navy by BAE Systems in Barrow-in-Furness.

Armed with Tomahawk land-attack missiles and Spearfish torpedoes, the 97m-long stealth submarine is claimed to surpass its predecessor - HMS Astute, which was launched in 2007 - in terms of its levels of completion.

Unlike HMS Astute, Ambush will not return to land once she is rolled out of BAE’s 25,000m2 Devonshire Dock Hall.

Speaking at the naming, John Hudson, managing director, BAE Systems Submarine Solutions, said Ambush is in an excellent state of readiness, an achievement attributed to all involved in her construction.

Hudson told The Engineer that delivering a programme as large and complex as Astute requires both an evaluation of technical solutions and the method of build that will bring about efficiencies for the company and an acceptable final product for the customer.

‘It’s several years ago since we chose the equipment and made the decision around the design,’ said Hudson.

He also said the company is looking at bringing in components that can be introduced to the submarine more easily, making it more cost effective. He noted that progress in electronics means elements of the combat system can be bought at a more cost-competitive price.

An innovation from the agricultural industry is to be integrated into the programme, namely a low-pressure (LP) blower, which is used to remove moisture from grain.

This off-the-shelf kit would be employed to fill the buoyancy tanks that enable the submarine to surface and flush out the air supply in the case of fire.

‘It sounds funny to say we used something from the agricultural industry but it is quite a sophisticated machine - it is an LP blower that has electro-magnetic bearings, so it’s quite quiet as well,’ said Hudson. ‘We were able to look at that machine and see that it would actually meet those requirements for Astute class.’

Another notable efficiency gain is said to have been won during diesel generator trials, which began the commissioning of the propulsion systems. The trials began in May 2009 and were completed in seven days, compared with three weeks with HMS Astute.

Parallel to this are the added pressures on public spending to reduce costs.

‘There’s a huge challenge on all lines of public spending to reduce costs and defence is no different,’ said Hudson. ‘Submarines are big and expensive defence products and they attract a lot of attention, so we are under a great deal of scrutiny to see how we can deliver this fantastic capability in a more affordable price.’

Hudson added during the naming ceremony that the company remains committed to ensuring its apprenticeship, training and graduate recruitment schemes are able to keep the Astute programme on target for the Royal Navy.

The naming of HMS Ambush by Lady Anne Soar, the wife of Admiral Sir Trevor Soar, will be followed by the submarine’s rollout onto the ship lift and lowering into Devonshire Dock where it will begin the next phase of commissioning.

Ambush Facts

Advanced nuclear technology means Ambush will never need to be refuelled.

Ambush is able to circumnavigate the world without surfacing and her dived endurance is only limited by the amount of food that can be carried and the endurance of the crew.

Ambush can manufacture its own oxygen and fresh water from the ocean.

The Astute class is the first Royal Navy submarine not to be fitted with optical periscopes – instead the vessel employs high-specification video technology. The images are delivered into the submarine via fibre-optic cables.

Armed with Tomahawk cruise missiles, Ambush can strike at targets up to 1,000km from the coast with pinpoint accuracy.

Ambush’s Sonar 2076 sonar suite has the processing power of 2,000 laptop computers. It has the world’s largest number of hydrophones, providing the Royal Navy with the ’biggest ears’ of any sonar system in service today.

The command deck module, on which the sonar suite sits along with the other combat systems and platform control systems, was shipped into the submarine hull in four days, compared with 17 on the first of class Astute. This involves inching the 220-tonne heavily outfitted module into the open submarine unit with, in places, just centimetres of clearance.

Source: BAE Systems