Breaking cover: Nuclear-powered submarines have been used by the navy since the 1960s
It’s hard to argue with experience. The managing director of BAE Systems’ submarine business had the ideal preparation for his role: 28 years in the Royal Navy, many of which were spent onboard subs themselves. Thus Tony Johns knows firsthand what he is talking about when he says life on a submarine is “not without its sacrifices”.
Johns, who has been at the helm of BAE Systems Submarines in Barrow-in-Furness, Cumbria, since last year, went straight from comprehensive school to sea as a submarine marine engineer, serving on HMS Splendid, a nuclear-powered Swiftsure-class submarine that was launched in 1979 and supported British forces around the globe, and HMS Trenchant, a Trafalgar-class submarine commissioned 10 years later.
He was also the first marine engineer officer of the Trident submarine HMS Vengeance, which was completed at Barrow in 1998. Johns is a chartered engineer and IMechE member.
Submarines in Britain fall under two types: hunter-killers, which carry out a variety of roles, and subs designed to carry the country’s nuclear deterrent, Trident. The latter are known as SSBNs, or ballistic missile submarines.
The most recent hunter-killer type to be built is BAE’s Astute class while the current SSBNs form the Vanguard class. Both types are nuclear-powered. The first British nuclear-powered submarine was commissioned in 1960.
BAE Systems launched Artful, the latest Astute-class submarine into the dock at its site in Barrow-in-Furness, in May. The first of the class, called Astute, was launched in 2007 and commissioned in 2010, and the second, Ambush, was launched in January 2011, and commissioned last year. HMS Artful is the third of seven Astute-class submarines.
“Would we like to ultimately be involved in a programme to replace Astute?” asks Johns. “Of course. But that is a decision for the government.”
There exists a technology roadmap known as the Maritime Underwater Future Capability Programme, which outlines potential future submarine designs for the Royal Navy. The initial blueprints for this will be developed in about seven years, and it is not certain they will be a straightforward replacement for Astute. Unmanned vehicles could be involved, it is thought.
Future vision: Successor will one day carry the UK's nuclear deterrent and is at the design stage
The design programme for Successor, the programme to replace current SSBN, will last for five years, and is three-and-half-years down the track. BAE has started to buy long lead time items for the programme with a view to construction beginning in 2016. “It’s all systems go and we have 1,400 people working on that programme,” says Johns. He adds that BAE has learnt a lot of lessons from Astute, which he concedes has had a “troubled history”.
BAE Systems was forced to issue a profit warning in December 2002 as a result of the cost overruns and delays it was experiencing with the Astute class as well as the Nimrod MRA4 maritime reconnaissance attack aircraft, which was cancelled in 2010 as a result of the Strategic Defence Review.
The delays were caused primarily by problems using CAD design software. Johns says: “Launching Astute boat three was a great day for us. The programme still has challenges, like any nuclear submarine programme. Inevitably, you get more experienced. We aim to get even better.”
Dan Allin, a consultant at engineering design firm Frazer-Nash in Bristol, worked for some time at Devonport Royal Dockyard, now part of Babcock International, on programmes to refit nuclear submarines. He now specialises in nuclear submarine design, civil nuclear decommissioning, research initiatives for military aircraft, and providing engineering management advice to the MoD. About half his time is spent on submarine design projects including the Successor programme.
The primary emphasis in design is on safety, but the MoD also wants to reduce cost and improve submarine capability. “Any technology that can improve these three things is of interest to the MoD,” says Allin.
For example, lessons from the automotive industry could inform submarine battery technology. There are likely to be increasing levels of automation and some replacement of mechanical systems with electronic ones in the future, he believes, although mechanical systems are favoured because they have a proven safety record.
“Today’s technology isn’t necessarily able to deliver the required safety, security and integrity levels,” he says. “It is one of the key things holding it back for submarines. Engineers tend to err on the side of caution and go for mechanical designs.
“If a safety system has been proven to work for 30 years in service, there isn’t a good reason to change it. Having said that, there is a need to keep improving capability to keep one step ahead of the enemy.”
Part of this is down to reducing a submarine’s acoustic signature, which can be done by modifying the shape of the hull, the design of the propulsion system, and the design of the control surfaces. Mounting equipment inside the sub on a rubber raft means there is just an isolated rubber connection between kit and hull, which dampens vibration and cuts down on noise.
Powering submarines by nuclear reactors gave them the ability to operate indefinitely, a characteristic sailors obviously do not have. “The limiting factor became people’s sanity and carrying enough food,” Allin says. Submarine living conditions have improved over the decades with better, but rather misleadingly titled, “hotel services”, such as atmosphere control, which pumps in oxygen and removes methane and carbon dioxide, and individual accommodation. Conditions inevitably remain extremely cramped, although they have improved since the 1960s, when submariners would be expected to crawl around many spaces. In terms of conditions, an analogy can be made with going into space.
“The old joke was that people were the last thing to be considered in the design of a submarine.” Allin says.
Johns remarks: “In the end, you are constrained by space. In terms of habitation I’m not sure there has been a massive change. It is marginally better.”
A submarine patrol tends to last a maximum of three months. Allin says: “That is the timeframe that works best in terms of people not going crazy.”
Addressing the challenges of submarine design is a good one for the engineer, both agree. “Submarines are the ultimate challenge because you’ve got so many systems that are all interrelated. One system can have a big impact on another so it is important to be able to understand the interdependencies,” Allin says.
“You can get involved in the most complex product the UK produces. It’s a fantastic place for engineers,” says Johns.
The Astute and other BAE programmes are certainly providing opportunities, with some 200 engineers due to be recruited at Barrow this year. BAE’s apprenticeship programme for submarine engineers has also been expanded. “For people who want exciting, challenging careers that can last for more than 20 years, there is a great opportunity,” says Johns.
High overheads: Subs such as HMS Torbay are very expensive to design and build
BAE is keeping quiet on the notion of unmanned submarines being used widely in the future but it seems the impact UAVs has made on military aviation has perhaps inspired submarine designers too. Remote vehicles are already obviously used widely in civilian roles in oil and gas, for example. It is possible remotely operated underwater vehicles could be launched from submarines and used for surveillance or mine clearance.
“The key challenge for submarines is recovering an unmanned vehicle – that’s a knotty problem,” says Allin. “The challenge is in how you guide it back on board, and having got it back on board, how you ensure it hasn’t been tampered with. Getting things out of the submarine has been done for decades because they fire torpedoes. Getting them back into submarines is a new problem.”
Part of the difficulty lies in piloting submarines at a low speed, which is challenging. In addition, if an unmanned vehicle is released in proximity to the propulsion system, it potentially increases the submarine’s acoustic signature. But the potential is there.“Unmanned vehicles could allow submarines to detect anti-submarine warfare ships on the surface without getting too close,” Allin suggests.
Johns says he feels privileged to have served in the navy and gaining his engineering qualifications at sea. The practical emphasis of the job made him a better engineer, he says. “I was a better student and a more rounded engineer as a result.
“Being in the boat took my understanding of engineering to a higher level. There is something wonderful about operating the submarine. You get an innate feel for the boat and its foibles. That is satisfying as an engineer.”
Astute thinking informs sub design
HMS Artful, a 97m long, 7,400-tonne nuclear-powered attack submarine, began edging out of BAE Systems’ giant construction hall on 16 May and was lowered into the water the following day.
Artful, the third of seven Astute class submarines being designed and built for the Royal Navy, will now begin the next phase of its test and commissioning process ahead of sea trials next year. It will undergo a series of complex tests to prove the safety and operability of its systems before it departs BAE Systems’ site for the trials. The defence giant is the prime contractor in the Astute programme, and the UK’s only designer and builder of nuclear-powered submarines.
The first two submarines in the Astute class – HMS Astute and HMS Ambush – have been handed over to the UK Royal Navy, while the remaining four are in various stages of construction. BAE Systems is also leading on the design of a replacement for the Vanguard class of submarine, working alongside the Ministry of Defence, Rolls Royce and Babcock in a programme that employs more than 2,000 people – of whom approximately 1,400 are with BAE.
This number is expected to grow significantly throughout 2014 as the programme continues to gather momentum.
The Vanguard class is a class of nuclear-powered ballistic missile submarines, or SSBNs, in service with the Royal Navy. Each submarine is armed with up to 16 Trident II nuclear missiles.
The class was introduced in 1994 as part of the government’s Trident nuclear weapons programme. The class includes four boats: Vanguard, Victorious, Vigilant and Vengeance. They were built at Barrow-in-Furness by Vickers Shipbuilding and Engineering between 1986 and 1999. All four vessels are based at HM Naval Base Clyde west of Glasgow.
Show time for defence deign in Coventry
The latest digital design packages used for the development of the smallest consumer products right through to vital subsystems found on the largest structures like submarines, will be on show at October’s Engineering Design Show, which will take place at the Ricoh Arena in Coventry. The show was created to champion British engineering design and is entirely targeted at design engineers, many of whom work for defence firms such as BAE and consultancies like Frazer-Nash.
Last year more than 3,000 attended over two days and this year closer to 4,000 are expected to visit the show, for which there are already more than 200 market-leading engineering supplier companies signed up.
The show features a conference, free practical workshops and an exhibition demonstrating and promoting cutting-edge technology and innovation. Professional Engineering is a media partner for the show, which was created by Findlay Media.
Engineering Materials Live is a section within the Engineering Design Show specifically dedicated to the use and application of materials. Visitors will get the opportunity to attend an exhibition illustrating innovation and encompassing all aspects of the materials world.
As part of the event, the Electronics Design Show will provide exhibitors and visitors with an opportunity to take part in an event aimed exclusively at electronic design engineers.
Meanwhile, the Embedded Design Show offers a more focused event for the industry.
The Engineering Design Show takes place on 22 - 23 October in Coventry. For ticket details go to www.engineering-design-show.co.uk.