by James Jinks
The importance of Walter’s work was immediately apparent to the Royal Navy. Creasy noted that ‘We stand on the threshold of very considerable technical development and the submarine of the future may differ profoundly from the submersibles of the present and past.’32 The British hoped to capture all three Type XVIIB U-boats, but when they arrived at the Blohm and Voss shipyard they discovered that they had all been scuttled. On 17 July 1945, a meeting chaired by the Third Sea Lord and Controller of the Navy, Admiral Sir Frederic Wake-Walker, concluded that U-1407 should be raised and brought to the UK and that an experimental high-powered unit that was discovered in one of the occupied factories should be ‘bench tested’ in Germany and then brought to the UK for further research and development along with the essential German personnel.33
Although the UK and the US were still allied with the Soviet Union, the British government was very concerned about Walter’s HTP technology falling into Russian hands, even more so when Walter and his fellow scientists made it clear during their interrogations that they were ‘indifferent whether they worked for us or for Russia, as long as they were permitted to work somewhere’.34 There was, Cunningham noted, ‘no question that by bringing them over here we prevent the Russians getting at them and also taking advantage of their brains and knowledge’.35 Despite a concerted effort to prevent the Russians obtaining any of the advanced German technology, Soviet forces had occupied a facility in the town of Blankenburg that had been involved in the design of the Type XVII as well as Walter’s hydrogen peroxide drive.36 They had also captured the plans for the Type XXVI Walter-boats. In July 1946, Cunningham warned that the Walter propulsion system was ‘known to other powers and it is essential that we should have, as soon as possible, experience in the construction and use of such submarines’.37
MODERNIZING THE WARTIME FLEET
What the British found in Allied occupied Germany had a profound impact on the Royal Navy’s future submarine policy. In February 1945, Creasy had concluded that the Royal Navy’s future submarine construction should proceed in two directions. First the construction of an experimental submarine to investigate requirements for what was called a ‘true submarine’. He envisioned a submarine based on the ‘A’ class design, but with improved battery capacity to enable short speeds of up to 20 knots to be achieved. Second, he envisaged the construction of three improved submarines in 1945, based on ‘A’ class, but with a redesigned Control Room to incorporate new radar equipment, a modified snort mast that could be raised and lowered in the same way as a periscope, and a new hull, built from improved steel to allow greater diving depths.38
However, in August 1945, Creasy informed the Secretary of the Admiralty that ‘as a result of further consideration, including study of German policy and design’, his ‘view on the development of the submarine of the immediate future’ had ‘undergone some changes from those expressed’ in his February 1945 memorandum. In particular, his initial conclusion that the Royal Navy should construct an improved ‘A’ class submarine had ‘changed profoundly’.39 ‘The decision that has to be made,’ Creasy wrote, ‘is whether to perpetuate the present policy of high surface qualities and go for improvement on these, which was broadly speaking my original intention, or whether to accept that no future submarine construction would be justified that was not based on the tactical use of the “Snort” and on high submerged performance.’40
Creasy concluded that the overriding requirement was for a submarine capable of high submerged performance. Strategically this was ‘required in order to enable a submarine to move rapidly from one area to another or to traverse a danger area in the minimum of time’. Tactically, high submerged speeds were required for three reasons. First, to enable an attacking or intercepting position to be reached in the face of air opposition, something that could not be achieved while a submarine was snorting due to the amount of wake caused by the snort tube. Second, for evading surface craft after an attack, primarily in a patrol area close to an enemy’s base where a large concentration of anti-submarine operations could be expected. Third, in order to attack surface ships and later, as we shall see, submarines.41
Creasy no longer considered it ‘desirable to proceed with the design of an improved “A” class’ and recommended a ‘radical change’: a new submarine built around the ‘ “Snort” at the sacrifice, where necessary, of surface qualities’ in order to increase submerged speed. This, in effect, replicated the German policy with the Type XXI U-boat. But Creasy was far more ambitious when he argued that the Submarine Service ‘should be prepared to go further than have the Germans in subordinating the attributes required for surface performance to those requisite for submerged performance’. This, Creasy explained, meant ‘the surrender of gun power, acceptance of comparatively moderate cruising speed on the surface, and probably of reduced sea-keeping qualities and manoeuvrability on the surface’. Nevertheless, he felt it would be a mistake ‘to embark on such a design before we have completed first-of-class trials of the Type XXI submarine and are so able to gain maximum value out of the German mistakes as well as out of the merits of the German design’. He also questioned ‘whether it would be justifiable to proceed with the design before we know more about the performance of the Walter engine’. He recommended constructing an experimental ‘true submarine’ as well as three additional submarines equipped with both the Walter drive and with normal diesel and battery propulsion.42
In reaching these conclusions Creasy was well aware that ‘requirements change and will continue to change, so that no design can ever be considered more than up to date at the moment of its acceptance’.43 He believed that the Royal Navy’s ‘ultimate aim must be to produce the “true submarine” with all surface qualities sacrificed to submerged qualities, with a really high submerged speed, and the ability to remain submerged up to the greatest maximum depth for an indefinite period. This was my view eight months ago and this is my view today.’44 At the same time, he recognized that such a development depended ‘entirely on the production of an engine of the closed-cycle type’. Yet nothing he had learned from German sources convinced him that such an engine was ‘yet in sight’ and he did not believe that one could be developed ‘for a long time yet to come, even if the possibilities of atomic energy are taken into account’.45 (A few weeks earlier, the United States had dropped the atomic bombs on Japan; the power of atomic energy was on everyone’s minds.)
Creasy’s mention of atomic energy as a possible means of propulsion was prescient. Individuals within the Admiralty recognized the potential of using atomic energy to propel submarines. ‘The atomic reactor is well suited to submarine propulsion, developing full power under all conditions, and quite independent of whether the submarine is on the surface or not,’ noted Jack Daniel, a young naval architect from the Royal Corps of Naval Constructors, in a 1947 paper to the Royal Institute of Naval Architects.46 Between 1946 and 1950 a small team of up to two naval Scientific and two Engineer Officers was incorporated with the Atomic Energy Research Establishment at Harwell to keep under study the possibilities of applying atomic energy to ship propulsion. A few officers from the Naval Staff Divisions and Technical Departments were, under special security restrictions, kept informed of relevant research and development in the atomic field with the aim of guiding and stimulating thought within the Admiralty to the same end. Progress was reviewed at meetings convened from time to time by the Deputy Controller (R&D) but very little was achieved.47 ‘Although such a system appears a possible development, it seems very unlikely that fissile material would be economically employed in a submarine rather than in atomic bombs,’ noted one 1947 Admiralty paper on submarine development.48
Due to lack of fissile material, facilities and trained personnel, it was impossible to institute anything more than the sketchiest preliminary investigations. These identified the problems associated with applying atomic energy to submarines, such as a need for new submarine designs and an extensive testing programme. ‘Difficulties a
ssociated with the introduction of an entirely new propulsion system would undoubtedly arise,’ noted the same 1947 paper. The Navy recognized that ‘eventual success is not an unreasonable expectation’ but concluded that ‘Such a vessel is many years away and so little is known about it that there seems little point in discussing the matter further at this stage except to say that 30 knots for six months does not seem an unreasonable figure for its mobility. (Six times round the world!!)’49 This early dismissal of atomic energy would plague the Navy and the Submarine Service for years to come. With atomic energy, as well as other types of propulsion systems a distant prospect, Creasy recommended that the Royal Navy ‘should proceed with the building of the experimental type “true submarine” for the purpose of answering all the problems that will arise in building a craft that will take the engine when it does materialise’.50
The Royal Navy’s focus in the immediate post-war period developed along two lines: first, the continuation of Walter’s work, the development of a Hydrogen Peroxide programme; and, second, the modernization of the Royal Navy’s wartime submarine fleet. Both were aimed at developing a submarine with a high submerged speed. Experiments with captured German HTP propulsion units had produced ‘satisfactory results’. By 1946 all the important components at the Walterwerke had been transported to Vickers in Barrow, where Walter and seven of his key staff and their families were taken to work. The Royal Navy’s Engineer-in-Chief considered that it was ‘essential that this research should proceed, as the whole future submarine policy depends on the successful development of these engines; this matter is of outstanding importance and urgency’.51 As the Navy’s knowledge of the technology improved, many in the Admiralty besides Creasy began to believe that HTP was the answer to developing a true submarine. At a February 1946 meeting to review progress, the Admiralty’s Deputy Controller (R&D), A. P. Rowe, argued that ‘next to the atomic bomb’ the hydrogen peroxide propulsion system and the true high-speed submarine, ‘would present the greatest threat to the Commonwealth in war’.52 In a July 1946 memo to the Cabinet, the First Lord of the Admiralty, George Hall, added that the ‘development was revolutionary and will have far reaching effects on submarine warfare’.53
HTP development progressed in two directions. The first involved refitting the raised German U-boat, U-1407, in order to obtain high-speed trials data. The Americans took U-1406 but did not operate her. U-1407’s refit was completed at Vickers under Walter’s supervision in 1947. In 1948 the submarine was commissioned into the Royal Navy as HMS Meteorite and put through rigorous sea trials off the west coast of Scotland. While the trials illustrated that the ‘operational possibilities of a very fast moving submarine are obviously enormous’, they also revealed a number of disadvantages. The most serious was the high cost of HTP, at least £300 per ton. It was also in short supply and Meteorite required a storage ship to carry it as well as a full-time escort, which added further to the cost. The submarine was also very unstable on the surface, unable to stop quickly in an emergency and very noisy. Yet the trials report concluded that:
It is realized that the disadvantage of expense of an HTP submarine is undoubtedly large. But while it remains the only proven method of very high speed propulsion, it is considered that the disadvantage is outweighed by the speed/time factor. This speed would probably be used mainly for escaping after an attack. With its help big changes of direction and depth could rapidly be made whilst at the same time, large distances are being covered, thus increasing by enormous proportions the difficulties of an escort vessel.
Full-scale trials took place between 17 March and 30 April 1949 and Meteorite’s Captain, Oliver Lascelles, concluded that the submarine was ‘an outstandingly difficult boat to handle on the surface’ but that she was ‘outstandingly easy to handle dived’.54
Meteorite’s trials confirmed what many in the Admiralty already believed, that the Royal Navy’s existing submarines ‘for all practical purposes’ had reached the ‘maximum limit of speed and endurance’. ‘It is clear,’ argued one Admiralty paper at the time, that an HTP-powered submarine:
would have a very considerable advantage over a battery driven submarine, both in reaching an attacking position and in evading A/S [anti-submarine] hunting craft after an attack … In order that our submarine fleet should maintain not only its offensive potential relative to other nations but, equally important, its value in the training of our A/S forces, it is most necessary that a practical form of such a propulsive system should be developed as soon as possible.55
Two experimental submarines, E14, Explorer, and E15, Excalibur, both equipped with HTP machinery, were included in the 1945/6 and 1947/8 naval building programmes and the Admiralty had tentative plans to build fourteen such vessels to act as fast underwater targets for the Royal Navy’s anti-submarine forces.56 However, concerns about the cost and supply of HTP remained. In wartime Germany adequate supplies of HTP had been produced regardless of the cost. In post-war Britain the circumstances were very different. The capital cost of constructing a plant in the United Kingdom capable of producing 1000 tons of HTP a year was estimated at around a million pounds, while the manufacturing cost of HTP was now around £200 a ton. Once operational, Excalibur and Explorer were expected to use 30 tons of HTP an hour when operating at full power while submerged. Assuming both submarines ran at full power for 100 hours each year, their combined annual consumption of HTP was expected to be around 6000 tons, a high proportion of the planned total manufacturing capacity of the country, which was expected to reach a maximum of 7700 tons a year in 1952–3. This was insufficient by a substantial margin to support a large HTP-fuelled submarine fleet.
In September 1949, a paper produced for the Ship Design Policy Committee recommended that because of the problems with HTP, work on Explorer and Excalibur ‘should proceed as scheduled, but that no consideration should be given at the present time to proceeding with further HTP-driven submarines unless a sudden emergency demanded reconsideration of this policy’.57 The Admiralty Board agreed and effectively rejected HTP as a means of propulsion for operational submarines.58 The twelve additional HTP submarines were cancelled, while work on the two experimental craft, Explorer and Excalibur, was to proceed as planned as submarines capable of ‘speedy evasion or attacks from under a convoy followed by rapid escape were possibilities of such danger to our seaborne communications that it was imperative for us to produce submarines of comparable performance, so that effective counter measures could be developed by our A/S forces’.59 Due to financial constraints brought on by the 1949 devaluation of sterling and the rearmament programme stimulated by the Korean War, which broke out in June 1950, construction of HMS Explorer and HMS Excalibur did not begin until July 1951 and February 1952.60
The decision to cancel the twelve HTP submarines was the correct one. There were simply too many unknowns. The US Navy, which had been conducting its own experiments with HTP since the end of the Second World War, had also concluded that HTP’s economic and logistical problems rendered its use in operational submarines impracticable.61 Both Navies continued with their HTP research programmes well into the 1950s, but they also explored other means of submerged propulsion which would give comparable results at greatly reduced running costs. Both the Royal Navy and the US Navy concluded that after HTP the most promising means of propulsion was one that used oxygen instead of HTP as the oxidant.62 The British considered waiting for the results of the American development programme in order to ‘adapt to our use the most satisfactory of their designs’, but this was dismissed by the Navy’s Ship Design Policy Committee because of differences in technical requirements, submarine design and specifications.63 In November 1949, a UK Working Party on Submarine Propulsion was formed to ‘survey the whole of the research and development programme relating to underwater propulsion of submarines by means of stored oxygen, and to direct effort into the most practical channels’.64
The United States Navy was also investigating the possibility of using
atomic energy to power its future submarines, but up until the late 1940s its efforts consisted of a series of haphazard projects spread across various research laboratories in the United States.65
FOSM’S EMPIRE
During the war Admiral (Submarines) and his staff were accommodated in three floors of a modern block of flats in Northways. When the war ended Creasy transferred his headquarters back to the pre-war home of the Submarine Service at Fort Blockhouse in Gosport, next to Portsmouth Harbour. By 1948, the Admiral (Submarines) title had been replaced with the new title of Flag Officer Submarines. In the immediate post-war years the Royal Navy’s submarines were organized into five flotillas, which were later known as divisions and eventually renamed squadrons with the adoption of NATO nomenclature in 1952. The flotillas consisted of the 2nd Flotilla, based in Portland and operated from a depot ship, HMS Maidstone; the 3rd Flotilla operating from a depot ship, HMS Forth, at Rothesay; and the 5th Flotilla in Portsmouth.66
Admiral (Submarines) also possessed a far-flung empire of Submarine Flotillas stationed in the Mediterranean and Far East, and later in Australia, Canada and Singapore. The 1st Submarine Flotilla was based in Malta and was serviced by the submarine depot ships HMS Wolfe and later HMS Forth. Its submarines were painted ‘Mediterranean Blue’ as the sea was often so clear that an aircraft could visually track submarines operating at depths of up to 100 feet. Submarines assigned to the flotilla spent much of their time conducting anti-submarine exercises with foreign navies such as the Americans, French and Greeks. The 4th Submarine Flotilla, serviced by the depot ship HMS Adamant, spent the immediate post-war years moving around the Far East, with periods in Hong Kong and Fremantle, Western Australia, before it finally settled in Sydney in 1949. There it comprised two or three submarines which provided anti-submarine training to the Royal Australian Navy and Royal New Zealand Navy. By 1955, only twenty-six out of the forty available operational submarines were based in the UK.67
