Connect with us


The nuclear submarine that can remain underwater for 25 years



astute nuclear submarine - The nuclear submarine that can remain underwater for 25 years

In a Barrow-in-Furness shipyard, Stuart Godden, the director of engineering for BAE Systems’ submarines division in Cumbria, is narrating a slide show and comparing the UK’s latest submarines programme – the Astute class – to Nasa’s Space Shuttle programme. “They’ve got a crew of five to seven, we’ve got 97 or so,” he says. “They go out for a couple of weeks, we go out for 90 days.They typically went on 100 missions, we’ve got 25 years to operate.

“In terms of the environment, they’re 200 miles up, we’re hundreds of meters beneath the sea. It’s very benign up there, because there’s no pressure or corrosion, whereas it’s very high pressure and very corrosive under the sea.”

Eventually, he concedes some ground to the Shuttle programme: “Albeit, in getting there they have a very explosive force as they transit into outer space – clearly they’re a hell of a lot faster than we are.”

Godden’s mission is to communicate the scale of what’s been achieved with the delivery of Astute: the sub isn’t a more complicated ship, it’s a completely different realm of engineering. It will operate beneath the sea for months on end, during which time it may be attacked. Throughout its lifetime it will have a nuclear reactor onboard alongside missiles and close to 100 submariners.

Britain’s submarines could previously remain at sea for a maximum of 15 years before refueling. The new iteration will last for a quarter century – the only reason it will need to resurface is to take on food. But does Godden really think Astute was harder to build than a Space Shuttle? “They are two of the most challenging projects the world has ever undertaken,” he says. “It’s hard to be objective. All I’m trying to say is it’s at least as complex from my perspective.”

The Astute is the quietest submarine in the world. Almost every mission it will take part in will require stealth: eavesdropping in hostile waters, covertly delivering special forces (while submerged), tracking enemy vessels and aircraft, hunting enemy vessels and quietly hiding while waiting to launch its Tomahawk missiles (while submerged) at an onshore target that might be more than 1,500 kilometres away.

Although there are no definite dates, the seven Astute-class submarines are likely to be the Royal Navy’s only attack submersibles in the next decade, taking over from the Swiftsure class (all decommissioned) and Trafalgar class (decommissioned within ten years). The only other submarines the Royal Navy will operate are the four nuclear-powered Vanguard-class boats, which currently carry Britain’s nuclear weapons, and which will be superseded by the Successor class if the Government gives the go-ahead in 2016. Thirteen-hundred people are already working on Successor at Barrow’s shipyard.

Godden, 44, has been director of the engineering function, which supports the Successor and Astute programmes, since 2010. He joined the Barrow shipyard as a mechanical-engineering graduate 23 years ago, when it was owned by Vickers. The yard has built all the Swiftsure, Trafalgar and Vanguard class, as well as the Royal Navy’s first submarine, the HMS Holland 1, in 1901. Now it is owned by engineering firm BAE Systems. There are 3,500 people working on the Astute submarines, at a total cost of £10 billion. They have faced significant challenges. For instance, silencing a 97-metre-long, 7,400-tonne piece of metal with 100 people inside. Or equipping it with listening devices using arrays of hydrophones attached to all exterior surfaces of the submarine and some that trail behind when the sub is at sea (the loud pinging sonar you hear in films is rarely used because it reveals position).

“We created computer models of structures involved in the propulsion and pipework systems,” says Godden, “and then modelled how we thought noise would be transmitted through those structures and pipe systems to the hull, and then obviously we tried to damp those noise paths to make the boat as quiet as we possibly could.”

The full article can be found here.


Most Popular Last Week