by James Jinks
Once the SBS team was safely in the ‘lurking area’, the casing diver hit the Torpedo Loading Hatch five times to signal to the submarine that the team was ready. Inside Walrus, one of the crew informed the Control Room and the CO gave permission to release the stores. Outside, the casing diver waited for permission to cut a ring main to allow the stores to float to the surface. On hearing taps from inside the submarine, he replied with his hammer, and then cut the ring main with a diving knife. The stores, with pent-up buoyancy, shot towards the surface, still linked to the submarine by a long towline. With their stores floating the SBS team moved out of the lurking area and began to swim to the surface:
In pairs, we went up the towline and, whilst the Casing Diver waited in the lurking area, we inflated the Capella and got in and stowed the rucksacks and thankfully got the engine (a Johnson 40hp) running. We gave a red torch signal to the periscope and the Casing Diver was given the signal to cut the towline; he then re-entered the submarine.125
Once separated from Walrus the SBS team moved to the side of the fjord, where they lifted their Capella ashore, capsized it and stowed the engine and unwanted diving equipment underneath. They then made their way towards the target, which was located in an anchorage. The Marine continued:
We watched the vessel come in and anchor and, during the evening prepared our diving sets. The CO2 canisters had been compressed a bit during the submarine’s passage but apart from that all was well. We donned our wooly bears and dry suits … and whilst our two ‘mules’ [SBS1] and [SBS2] waited on land, [SBS3] and [SBS4] entered the water shortly after dark and dived. It was not a long swim and having placed our limpets on the hull we then returned to the shore and got into our skiing clothes ready to exfil. Rather than carry our diving kit, we cached it and made our way on skis throughout the night back to a position close to the cached inflatable.126
The SBS team then waited until nightfall before they prepared to row back to Walrus. The Marine described how:
We had the painful business of donning very cold dry-suits and wet-suit hoods and gloves that had frozen solid. Amazingly, again the outboard motor started and we headed towards the submarine RV in Bals Fjord. Using our pinger, once we were in the estimated position, the dived submarine homed in on us. We snagged the periscope and, shortly afterwards, the Casing Diver came to the surface and in pairs we dived down the fin along the casing to the lurking area. Recharging our RABA both in the fin and in the lurking area, in turn we re-entered the submarine via the SET.127
With the SBS having re-entered the submarine the casing diver stored the remaining equipment, slit and sunk the Capella inflatable and then re-entered the submarine.
These operations required extensive training and there were plenty of opportunities for incidents. One of the Marines taking part in ‘Cold Shoulder’ had a particularly close call on another exercise in waters off Gibraltar while standing on the casing of a submarine. Suddenly an Iranian frigate began to head straight for the submarine. The submarine CO ordered an emergency dive, leaving the SBS soldier on the casing. He was eventually ripped away, passed the propellers, which he narrowly missed and was dragged into their vortex. Eventually he stopped spinning and was left floating underwater. Fortunately the exercise was taking place during daylight hours and the Marine was able to swim to the surface, where he found himself facing the bows of the frigate, which passed him by yards.128
In January 1977, the same Marine was also involved in a tragic accident with HMS Orpheus, which was fitted with a new five-man chamber specially designed for exit/re-entry operations. On 15 January, Orpheus was conducting exercises with the SBS in Loch Long, in blustery and cold conditions. Orpheus was dived to 73 feet with her W/T mast raised and three SBS divers in the special chamber. Just as the SBS team prepared to exit and begin the exercise, Orpheus cruised into a patch of fresh water and the sudden change in water density caused the submarine to dive uncontrollably and speed up to maintain depth.129 As Orpheus continued to dive the safety diver, who was attempting to hold himself in position on the submarine’s casing was pulled off like a puppet by the tension on his communications line. On the surface, an SBS team sitting in a Gemini inflatable was pulled vertically downwards by Orpheus’s W/T mast as the submarine increased depth. The bowline then tore off completely.
The first Marine had already left the chamber when Orpheus hit the patch of fresh water. He attempted to return to the chamber to warn the other two members of his team but soon realized that he stood little chance of making it. He reluctantly pushed off the submarine’s casing and inflated his specialist suit. Orpheus was now so deep that for the first 15–20 feet of his ascent, the first Marine’s suit inflation had no effect whatsoever. It was only through his own vigorous swimming effort that he managed to start moving upwards. When he eventually surfaced he was quickly recovered by the SBS in the Gemini Inflatable. When Orpheus surfaced after blowing ballast to give the submarine positive buoyancy there was no sign of the other two Marines. After a surface search had been conducted it was clear that the two divers were missing. As the search continued most people believed that the two divers were alive, that they had swum ashore to find a telephone or make their presence known to someone. But the next day, they were found 10 yards apart in 221 feet of water. One had managed to get rid of some of his equipment, but in a frantic attempt to swim had lost one of his fins. Both Marines had died from drowning following HMS Orpheus’s dramatic dive.130
A naval Board concluded that the two Marines probably left the casing when the submarine was at approximately 105 feet, two minutes after the upper hatch indicated shut. It appeared that they were free of the chamber and on the casing breathing off their special RABA sets. They then tried to make it to the lurking area to recharge their breathing apparatus but when Orpheus’s ballasts blew they were swept off the casing as the submarine suddenly accelerated towards the surface. A diver could comfortably move about the outer casing, but only if the speed of the submarine did not exceed half a knot. Any faster and he would need to concentrate on holding on. If the speed exceeded 2 knots, he would no longer be able to hold on because of the force of water pushing against him. If he let go, there was a danger that he would pass through the propellers. Both divers had opened up their inflatable suits, but because they were so deep there was little air. They were also negatively buoyant. Lessons were learned. After the incident a special life jacket was designed for SBS divers that, when pulled, inflated a massive air bag capable of pulling a man in full operational equipment from a depth of 100 feet. The maximum speed for exit and re-entry was also reduced.131
THE ‘SWIFTSURE’ CLASS
On 27 November 1976, Vice Admiral Sir Iwan Raikes stood down as Flag Officer Submarines. His successor, Admiral Sir John Fieldhouse, was the first ‘post-war’ officer to hold the post, and the first to have held a nuclear command. Fieldhouse was very much a product of the Cold War, and the nuclear age, having served as First Lieutenant on board HMS Totem, which as we have seen conducted the Royal Navy’s first submarine intelligence-gathering operation against the Soviets. He had also commanded HMS Acheron, HMS Tiptoe, HMS Walrus and HMS Dreadnought and was responsible for the Polaris force during its formative phase in the late 1960s. He also held various posts on the Staff of Flag Officer Submarines at HMS Dolphin, all of which meant he was well versed in submarine matters and well prepared to take up leadership of the service.132
Fieldhouse recognized that if he did not move to Northwood he could lose control of his submarines. In early 1978, he therefore relocated the Headquarters of the Submarine Service from its traditional home in Fort Blockhouse, Gosport, to Northwood and assumed direct control of Commander Task Force 311 (CTF 311). There was now complete control over the submarine operational broadcasts; CTF 345 was next door and water could be divided between SSN and SSK operations and Polaris patrols. In order to test the new combined and integrated submarine operations centre Fieldhouse ran an exercise called Operation ‘Gratitude’ and o
rdered Royal Navy submarines to target any Soviet submarines that happened to be at sea at the time.133
Fieldhouse also supervised the introduction of an entirely new class of nuclear submarine: the ‘Swiftsure’ class. Work on the new boats began in the early 1960s, while ‘Dreadnought’ and the ‘Valiant’ class were building. However, as we have already seen, design work was interrupted by around three years because of the Polaris programme and it did not resume until the mid-1960s.134 This additional time allowed the naval architects ‘to consider the new design more carefully and to feed in the lessons learnt from operating Dreadnought, building the “Valiants” and the first SSBNs’.135 Known as the ‘Swiftsure’ class, its design team was led by a brilliant naval architect, the Assistant Director of Warship Design at Bath, Norman Hancock. Hancock was so determined to produce a submarine that was faster, stealthier and deeper diving than any contemporary vessel that disbelieving naval staff in London had to repeatedly revise their expectations. Hancock rejected the American teardrop hull form and used one of equal diameter throughout, which combined a longer pressure hull within a shorter overall length. According to Hancock, the class was ‘probably the biggest single step forward we have made in nuclear submarine design’.136 His design philosophy was to:
make all improvements which were practicable within existing technologies, with existing materials and without extensive research or development. This necessarily precluded large changes in reactor technology, but permitted redesign of the hull and of the layout of the weapons in the front-end as well as of the machinery in the back-end. Our aims were to simplify wherever possible by cleaning up and removing all unnecessary duplication and to introduce the necessary improvements which would produce a faster, stealthier, safer, deeper diving and more easily maintainable weapons platform.137
The design condensed the machinery to such a degree that in order to maintain Swiftsure’s longitudinal centre of gravity, Hancock had to introduce an empty space aft of the engine room, known as ‘Hancock’s hole’.
With a submerged displacement of 4922 tons, and a deep surface displacement of 4478 tons, the overall length of the ‘Swiftsure’ class was 271 feet with a maximum diameter of 32 feet 3 inches. The final design was 14 feet shorter and one foot less in diameter than the ‘Valiant’ class and the diving depth was increased from 750 to 1250 feet. The external shape of the submarine was cleaned up and compacted to reduce hull resistance. The bridge fin was also reduced in size and the forward hydroplanes made retractable. The first of class, HMS Swiftsure was fitted with a series of highly secret special sophisticated swept-back conventional propellers designed to reduce cavitation, which gave a submerged speed of approximately 28 knots, and a surface speed of approximately 12 knots. Subsequent submarines of the class were fitted with a pump jet driven by two steam turbines, which contributed to the much fuller and blunter stern of the submarine design.138 The class was powered by the same PWR1 nuclear reactor used in the ‘Valiant’ and ‘Resolution’ classes, but it featured a new, more advanced and longer-lasting core, known as Core B, which had double the life of and a maximum power rating approximately 20 per cent greater than the Core A.139 The class was also significantly quieter than earlier British SSNs. Propulsion turbines, turbo generator sets and main gearbox were all mounted on a moveable raft which was noise-isolated from the pressure hull. At full power radiated noise in the ‘Swiftsure’ class was reduced to a level comparable with the quietest main machinery mode of the ‘Valiant’ class.
The class was also fitted with an improved version of Type 2001 sonar and the main array was repositioned at the fore end of the submarine in a downward position to exploit what was known as the bottom-bounce technique, a method of using the ocean bottom to increase the range of sonar. Other sonar outfits included the Type 2007 long-range low-frequency passive sonar and Type 2017 frequency analysis equipment, as well as the normal range of echo sounders, U/W telephones and cavitation indicators. The class also differed from previous Royal Navy SSNs in that it was fitted with five torpedo tubes in a modified arrangement, instead of the six in the ‘Dreadnought’, ‘Valiant’ and ‘Resolution’ classes, with a total of twenty torpedo stowage positions – all of which were capable of accepting the new Mark 24 torpedo.
The first of class, HMS Swiftsure, commissioned on 17 April 1973, and was followed by five others: HMS Sovereign in July 1974; HMS Superb in November 1976; HMS Sceptre in February 1978; HMS Spartan in September 1979; and HMS Splendid in March 1981. Once again there were construction problems. HMS Superb was to have been built with the new QI(N) high-yield steel. However, as in previous programmes the British steel industry struggled to meet the demanding build schedule and the Royal Navy was once again forced to turn to the Americans for supplies of the American-made HY80 steel. Strikes, overtime bans, lockouts, the energy crisis of 1973–4, and demarcation disputes, as well as a lack of steelworkers, electricians, outfitters and pipe fabricators, contributed to other delays. However, as more of the class entered service, they came to be universally recognized as one of the most successful of all post-war nuclear submarines. Most operated out of the 2nd Submarine Squadron in Devonport.
The ‘Swiftsure’ class was also the first Royal Navy nuclear submarine designed with under-ice operations in mind. Since Dreadnought’s patrol to the North Pole in 1970, the Royal Navy had kept a close eye on the icy waters of the Arctic Ocean. In the early 1970s, the Americans placed acoustic arrays in the ice cover, which provided regular scientific and operational intelligence and demonstrated that the Russians were deploying their submarines under the ice. The polar ice cap of the Arctic Ocean was now an area of utmost importance to both East and West, an area that neither side could permit the other to dominate. The US Navy recognized that scientific data, operational experience and simple presence in the Arctic had to be accrued, developed and maintained so as to understand the geographical and strategic aspects of the environment. In 1973, the first ever war game between two US Navy SSNs, USS Hawkbill and USS Seadragon, was conducted in the Bering Sea. ‘The game was on,’ wrote the chief architect of the US programme, Dr Waldo Lyon, ‘two of us in the shallow water under the ice, and that’s when we learned … no way … we don’t know how to do this.’140 In order to address this deficiency the US Navy started to send an SSN under the Arctic ice cap every two years.
The Royal Navy was still relatively inexperienced with under-ice operations and in October 1976 Fieldhouse decided to send one of the new ‘Swiftsure’ class submarines to the North Pole. HMS Sovereign, under the Command of Commander Michael Harris, departed Devonport on 1 October and in cooperation with HMS Narwhal took part in Exercise ‘Brisk’, travelling to the North Pole in order to conduct geophysical survey work and collect data on the underwater profile of the ice cap.141 The first stage of the operations centred on the ice edge, where the extraordinary and unstable water conditions, combined with the high background noise level in anything other than flat calm weather conditions, made it an ideal area for remaining undetected. However, for nuclear submarines, the ice edge was a more awkward area in which to operate than either the open ocean or under the Arctic pack ice and Sovereign spent a considerable amount of time dodging growlers and icebergs. Conditions under the Arctic ice were far more stable and when Sovereign surfaced at the North Pole on 23 October, the submarine was wedged into a comfortable and secure berth in the ice sheet. While on the surface Sovereign was unable to establish contact with the UK due to faults with the submarine’s communication masts and the now well-known high-latitude communication problems first encountered by HMS Dreadnought in Exercise ‘Sniff’. After three days, Sovereign’s failure to establish communication created something of a media storm back in the United Kingdom as the press got hold of the story and incorrectly concluded that the submarine was lost beneath the ice.
Despite these relatively minor problems the patrol confirmed that the ‘Swiftsure’ class could easily handle the operational aspects of under-ice operations. The Ca
ptain of the 2nd Submarine Squadron in Devonport, Richard Heaslip, concluded that ‘any “Swiftsure” Class SSN can be deployed at very short notice for under-ice operations’.142 This, according to Fieldhouse, was ‘highly significant’ as the ‘S’ class could now be sent to conduct an ice patrol without special training or modification.143 Sovereign’s CO recommended deploying a Royal Navy SSN to the Arctic at least once every five years in order ‘to keep the art alive’ and that on the next occasion at least two SSNs should take part in operations in order to improve knowledge of how Royal Navy sonars performed under the ice.144 Fieldhouse agreed and in August 1977 he opened discussions with the United States about participating in combined US/UK under-ice exercises, using HMS Sovereign and a US SSN in April 1979.145
The ‘Swiftsure’ class was also fitted with new technology that significantly enhanced the capability of Royal Navy submarines to track Soviet submarines. In the early 1970s, the Admiralty’s Underwater Weapons Establishment (AUWE) at Portland was tasked with producing the first computer-assisted Tactical Data Handling System for the ‘Swiftsure’ class. The first system, known as the Tactical Data Handling System, or DCA, was capable of accepting and displaying information generated by active and passive sonars and was fitted in HMS Swiftsure in 1973, with tactical trials in 1975. In combination with advanced mathematics, these new computers were able to automate the manual processes for tracking contacts, removing the need to depend on a myriad of manual plots, slide rules, calculators, stopwatches and position-keeping devices that previously placed big demands on a submarine’s manpower. One of the most important advances was the realization that the same complex equations used in US guidance and navigation systems developed by an American control engineer, Rudolf Kalman, could be adapted and applied to more accurately determine the movement of a submerged submarine contact.146 The DCA system was subsequently fitted in the next two ‘Swiftsure’ class submarines, HMS Sovereign and HMS Superb and it was also used as the Command part of a new Target Tracking and Fire Control system known as DCB, which was first fitted to HMS Sceptre.