Submarines: UK subs: an Astute decision | ADM November 2012

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The UK’s Astute class submarines have had their well publicised issues for both technology and schedule, not unlike the Collins class. And like the Collins class, there is a replacement already on the drawing board.

The Royal Navy operates six fleet submarines (SSNs), of the Trafalgar and Astute classes, and four ballistic missile submarines (SSBN), of the Vanguard class. All of these submarines are nuclear powered. The service also owns the LR5 Submarine Rescue System, the same system that Australia leases through James Fisher.

The Astute boats are still in the process of being built at BAE Systems Barrow-in-Furness dockyard. The yard, previously owned by Vickers, has been the site of the UK submarine and ship building for generations.

There are six fleet submarines on active duty – five Trafalgar class submarines and one Astute class submarine, HMS Astute while the second of the seven boats, Ambush is now in the water but not yet operational.

BAE Systems is the design/technical authority and lead contractor for the Astute Class submarine program, providing design, build and in-service support for seven Astute submarines for the UK Royal Navy.

These submarines are armed with the Spearfish torpedo for anti-submarine and anti-surface warfare. Some are also armed with Tomahawk cruise missiles for attacking targets on land. The Fleet submarines are capable surveillance and reconnaissance platforms. A total force of seven Astute-class submarines is planned. As of April 2012, the first is in service, the second is launched and being fitted out (Ambush), three are under construction, the sixth is ordered, and the procurement process has been started for the seventh.

Bridging the gap


This seventh boat will act as a bridge across the shipbuilding valley of death (see P18 for more on this gap in Australia) between the Astute and the Maritime Underwater Future Capability (MUFC), the UK version of the Future Submarine.

These will follow on from the Astute class, and possibly replace the Trafalgar class. Some reports have suggested that the MUFC studies may result in a single class of multi-role submarines to replace the Trafalgar class, Vanguard class SSBNs and eventually the Astute class. This would require a submarine capable of launching conventional land-attack missiles, some form of nuclear missile (ICBM or tactical nuclear missile) as well as conventional submarine munitions including mines and torpedoes.

The four ballistic missile submarines (SSBN) of the Royal Navy are all of the Vanguard class. Vickers Shipbuilding and Engineering Ltd, now BAE Systems Submarine Solutions built them all. The SSBN flotilla or bomber ‘fleet’ tends to be almost a separate entity, for example it rarely uses pennant numbers preferring to use hull numbers, thus Vanguard 05, Victorious 06, Vigilant 07 and Vengeance 08.

The four Vanguard class boats are responsible for the UK’s nuclear deterrent, and use the Trident missile system. Each boat can carry up to 16 Trident II D5 Missiles, each of which may carry up to 12 nuclear warheads. It is UK Government policy to limit the actual number of warheads carried to 48 per boat.

There has been at least one SSBN on patrol at all times for over 30 years, for a total of over 300 missions.

Speculation that the MUFC could be a combined nuclear deterrent and ISR platform have been raised but the UK government is still deciding on the best course of action. At this stage, a new generation of ballistic missile submarines is also being planned, following a December 2006 Ministry of Defence white paper which recommended that the nuclear weapons should be maintained into the 2040s. It advocated the currently preferred submarine-based system, as it remained the cheapest and most secure deterrence option available.

BAE Systems Submarine Solutions estimates that the build time for an Astute class submarine is 9.5 years from the initial cutting of steel to the launch of the boat. And while there will be some gains made through the learning curve of any such program build (the use of modular blocks where possible), the overall gains to be made through productivity and efficiency changes are likely to be minimal.

However, this modular approach for the bridge consoles saw the time involved a fit out period of 17 days for the first boat, threefor the second and now takes 1.5 days. But the boats have 10 kilometres of piping of various sizes alone throughout, the modular approach has seen some very complex pipe work go into constrained spaces.

Best of breed


As outlined by BAE Systems’ Brian Benn events manager at Barrow, 75 per cent of Astute is new technology with the remainder a best of breed solution from previous submarine building efforts (see figure right). One of the technology gains that they are most proud of is the fibre optic mast. No longer will the bridge have a huge periscope tube going up and down, a massive opportunity for design changes. A small post will pop up from the top of the boat, make a quick 10-second scan and disappear again.

Design and construction of the Astute Class is arguably the most challenging engineering project in the UK and has been described as “more complex than the space shuttle”, involving the production of over 7,000 design drawings. For the 4,450 BAE workers at Barrow, a company town in many respects, seeing chunks of submarine being trucked down the street has become a non-event in some ways.

The most startling realisation of a visit to the Devonshire dock hall (DDH), built in the 1980s for the construction of the Vanguard class, is the scale. Two Astute submarines are in varying stages of construction, are side by side. The mammoth structure of DDH and the boats inside them, swarming with workers, brings home the challenge that Australia faces in building its own fleet in country.

BAE Systems spent £204, 686, 294 last year across 2,100 companies in their efforts to build Astute class submarines.

The new assembly shop is a sight to behold. The raw material – steel plate – comes in at the far end of the gigantic building, where cutting machines produced parts for ‘kits’, which are then delivered to the welders, who construct gigantic hoops that will eventually be put together to form the pressure vessel, while also fabricating the towering surface structure (outer casing). Welding is the key skill and there is no room for error, illustrating perfectly the ‘lives at stake’ ethos that drives everyone to aspire to 100 per cent defect free work.

BAE Systems Submarines considers that it has the best welders in the world and theirs is by no means an easy job. The young men and women who weld wear rubber protective suits, masks and breathing equipment while they work in confined spaces in temperatures of 70 degrees Fahrenheit.

To put together a section of an Astute Class submarine can involve three miles of welding, consisting of hundreds of welds, all of which are thoroughly inspected not only by the welder at every stage, but also by their section leaders. The welds are X-rayed and if they are not up to standard the welders are taken off the line and sent back to Barrow’s welding school. Welding competitions and awards in the UK are populated by a lot of Barrow natives.

Skilled people


When Australia approached the UK in 2008 about support for the Future Submarine, the feeling from the UK was ‘good luck with that, we have our own hands full. Don’t steal our people’. Fast forward to 2012, and the attitude has changed somewhat. The push to collaborate where possible has been driven on both sides by a shortage of funds and people alongside a demand for more capabilities. How the two nations will work together as the MUFC and Future Submarine on finer details remains to be seen, but there is little doubt that there will be a strong working relationship between the two nations.

Note: The writer travelled to Barrow as a guest of BAE Systems.

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