The Bletchley Park Codebreakers

by Michael Smith

  In July 1944 Whitehall began consulting at Bletchley Park about what material they wished to scoop up from what would soon be occupied Germany. Suitably briefed, by early 1945, Intelligence Assault Units were moving into Germany with the forward elements of Allied formations, looking for all kinds of German documents, experimental weapons and atomic plant. Combined Anglo–American Target Intelligence Committee (TICOM) teams were despatched from Bletchley Park to Germany to seek out cryptographic equipment and Sigint personnel. They were not disappointed. Stopping at various German headquarters along the way they ended up at Hitler’s Berchtesgaden, where they found a Luftwaffe communications centre and a large amount of communications equipment. Eventually German POWs were persuaded to lead them to a vast haul of materials buried nearby and four large German lorries were loaded to capacity with the contents that were then unearthed. The team returned to Bletchley Park – which was increasingly referred to as ‘GCH Q’ – with its booty on 6 June 1945.

  GCHQ relocated and reorganized at the end of 1945. Some of its wartime equipment was constructed at the laboratories of the Post Office Research Department at Dollis Hill in north London, and it was no coincidence that the Director of GCHQ, Sir Edward Travis, chose to move the organization to a temporary site at Eastcote near Uxbridge in north-west London, only a few miles from Dollis Hill. Here it remained until 1952, when his successor, Eric Jones, oversaw the move to two permanent sites in Cheltenham.

  One of the most important battles won by GCH Q during 1945 was its struggle with the Treasury. In the autumn, while Travis was in the United States seeking to sustain the Anglo–American Sigint alliance, one of his deputies, Captain Wilson, was busy arguing for exceptional financial measures to help retain the best senior staff beyond the end of the war. Wilson warned that ‘there is a grave danger of us losing key personnel which are irreplaceable’. Accordingly, an early tranche of money was released while officials argued over the request for 260 officers as part of a core GCH Q staff of 1,010 (this compared with a wartime allocation of 8,902 staff). Travis returned in late November 1945 to join the fray. He explained that the large quota of senior staff was essential for a new ‘Sigint Centre’ at Eastcote, from which he would be able to provide a better service to Whitehall. His blueprint for the new GCH Q at Eastcote envisaged six main groups: Technical (Interception and Communications), Traffic Analysis, Cryptographic Exploitation, Cryptographic Research, Intelligence, and Cipher Security.

  By mid-December 1945, Travis had won the argument and had reached a deal with the Treasury that was ‘on the whole most satisfactory’. But in conveying these feelings to the Treasury he did not miss an opportunity to lecture them on the importance of affording good staff and facilities for GCHQ:

  The war proved beyond doubt that the more difficult aspects of our work call for staff of the highest calibre, the successes by the Professors and Dons among our temporary staff, especially perhaps the high-grade mathematicians, put that beyond doubt. We cannot expect to attract many men of that calibre but we should have suitable conditions with which to attract them.

  From his remarks I do not think Winnifrith [a Treasury official] realizes how in some spheres our work is akin to that of the scientific services. For instance, one of our mathematicians has evolved, and made mostly with his own hands, a prototype model of a telephone scrambler of a unique system, and one which gives very great security, and yet of a size that could be used in an aircraft or a car. Although very much wanted, this is a project on which Government scientific establishments have so far failed. Again, the theory on which some of our very secret instruments have been constructed must surely be regarded as a very considerable scientific achievement.

  Travis had rightly anticipated the shape of the main challenge that awaited GCHQ in the 1950s and 1960s, namely to stay ahead in a field that increasingly required cutting-edge developments in physics and electronic engineering, something that was likely to place intense strain on GCHQ’s budget.

  In the late 1940s, the key target for GCHQ was the Soviet A-bomb. The British Chiefs of Staff were fascinated by the problem of Britain’s relative vulnerability to attack by weapons of mass destruction and wanted forecasts on this crucial issue. The JIC ordered Britain’s codebreakers to focus their efforts upon this, together with other strategic weapons systems such as chemical and biological programmes, ballistic rockets and air defence. Although the JIC placed these subjects in a special high category of priority, it was to no avail. The Soviet bomb took the Western allies by surprise in late August 1949. Other Soviet activities, including espionage and diplomatic initiatives, constituted second and third priorities for GCHQ, but here too there were thin pickings. Many Soviet messages employed one-time pads which, if correctly used, could not be broken. The extent to which Britain was surprised by the Tito–Stalin split in 1948 underlines the limited success enjoyed against its diplomatic targets. Secure Soviet ciphers were only part of the problem. Moscow and its satellites used landlines, which could not be easily intercepted, instead of wireless transmissions.

  The limited headway that Britain and the United States had made with Soviet Bloc communications by the late 1940s, including the Venona programme, which attacked KGB intelligence traffic, was soon nullified by the espionage of William Weisband. Weisband was serving with the US Army Security Agency and was privy to most of what the West was obtaining from Soviet channels. As a result, on Friday, 29 October 1948, the Soviet Union underwent a massive change of code and cipher security, eliminating most of the channels that the West could read, including some machine-based, mid-level military systems. In part it was this catastrophe that prompted the British to follow the Soviets down the path of more extensive physical bugging in the mid-1950s. It also prompted the British and the Americans to accelerate their efforts to intercept Soviet telephone landlines by tunnelling under the Soviet sectors of Berlin and Vienna. Several tunnels are known to have been dug in these locations, but it is not unlikely that there were others.

  Difficult Soviet targets aside, GCHQ was nevertheless providing Whitehall with large quantities of material in the late 1940s, albeit of a secondary and tertiary order. They continued to attack the communications of many states with vulnerable cipher systems. Some neutral states were persuaded to adopt Enigma or Enigma-type machines previously used by the Axis, in the belief that these machines provided a secure means of communication. This was a belief that GCHQ did nothing to undermine. The JIC had requested material on subjects such as Arab nationalism and the relations of Arab states with the UK and USA, the attitude of the Soviet Union, France, Italy and the Arab states towards the future of the ex-Italian colonies, especially Libya. GCHQ was also urged to focus on the Zionist movement, including its intelligence services. These subjects proved more accessible. In 1946, Alan Stripp, a codebreaker who had spent the war in India working on Japanese codes, suddenly found himself redeployed to the Iranian border. During the Azerbaijan crisis of 1946, he worked on Iranian and Afghan communications (but not Soviet communications) with considerable success.

  Although GCHQ was always the largest postwar British secret service, much of its activity was hidden by the use of the signals units of the armed services for interception. Each of the three services operated half a dozen sites in Britain. GCHQ also had a number of civilian outstations including a Sigint processing centre at 10 Chesterfield Street in London, a listening post covering London at Ivy Farm, Knockholt, in Kent and a listening post at Gilnahirk in Northern Ireland. GCHQ had overseas stations hidden within Embassies and High Commissions overseas. There were also service outposts. In the Middle East, the base of Ayios Nikolaos, just outside Famagusta on Cyprus, became a critical intelligence centre, receiving further Army and RAF Sigint units as they gradually departed from Palestine, Iraq and Egypt. Further east, the Navy maintained its intercept site at HMS Anderson near Colombo in Ceylon, and the Army began reconstruction of its pre-war Sigint site at Singapore. But the main British Sigint centre in Asia after 1945 wa
s Hong Kong, initially staffed by RAF personnel. Here, together with help from their Australian counterparts, they captured Chinese and Soviet radio traffic.

  Despite London’s decision to give GCHQ the lion’s share of British intelligence resources and the tendency to bury some of the programme in other budgets, it was difficult to meet the expanding costs of Sigint. On 22 January 1952, the Chiefs of Staff had met together with the Permanent Under Secretary of the British Foreign Office to review plans for improving British intelligence. GCHQ came out on top in this exercise. Its cutting edge programmes, mostly in the area of computers and ‘high speed analytical equipment’ for communications intelligence, were given ‘highest priority’. The Chiefs of Staff continually reiterated the ‘very great importance’ of speeding up development and construction in these ‘very sensitive’ areas. By November 1952 a major review of British intelligence was underway. The process was prolonged by the primitive nature of available managerial instruments. Nevertheless, all were clear that in the short term the emphasis should be ‘for Sigint’. Eric Jones, the Director of GCHQ in the 1950s, reported that he was busy filling the 300 extra staff posts recently authorized. GCHQ had proposed a further increment for an extra 366 staff to follow. GCHQ was moving from strength to strength.

  As early as 1945, most English-speaking countries had committed themselves to postwar Sigint co-operation. Policy-makers at the highest level had come to expect a world in which a global Sigint alliance rendered enemy intentions almost transparent. They were not about to relinquish that privilege willingly. In the autumn of 1945, when Truman was winding up the Office of Strategic Services (OSS), America’s wartime secret service organization, he was also giving permission for American Sigint activity to continue and approved negotiations on continued Allied co-operation. All desired the maximum option. Yet the way ahead was strewn with obstacles and the package of agreements, letters and memoranda of understanding, often referred to as the UKUSA treaty, that sealed this alliance, was not completed until 1948. As this agreement emerged, Britain derived considerable benefit from her dominance over Commonwealth partners.

  The semi-feudal relationship which London enjoyed is no better illustrated than in Australia where Sigint operations were controlled by London. Only in 1940 did Australia establish her own separate organization. When this became the Australian Defence Signals Bureau, formed at Albert Park Barracks in Melbourne on 12 November 1947, it remained in the shadow of GCHQ. Four Australian applicants for the directorship were rejected in favour of Britain’s Commander Teddy Poulden, who filled the senior posts with twenty GCHQ staff and communicated with GCHQ in his own special cipher. During the winter of 1946–7, a Commonwealth Sigint conference was held in London, chaired by Edward Travis, during which each country received designated spheres of activity. Canada’s Sigint organization, under the long-serving Lieutenant-Colonel Ed Drake, suffered similar treatment. On 13 April 1946 the Canadian Prime Minister, Mackenzie King, authorized the consolidation of a number of wartime organizations into a small postwar unit of about 100 staff, known as the Communications Branch of the National Research Council (CBNRC). Again, the senior post was filled by staff seconded by GCHQ, prompting Canadians to say that CBNRC stood for ‘Communications Branch – No Room for Canadians’.

  Although GCHQ representatives were often over-awed by the scale of American Sigint resources, matters looked quite different from Washington. With the war over and an economizing Republican Congress controlling the federal purse-strings, resources for American communications intelligence (Comint) interception activities were remarkably tight before 1950. This led to a state of parlous under-preparedness prior to the Korean War. It also prevented the European expansion that American Sigint had hoped for. In 1949, US Army Security Agency interception units in Europe were still passing their product to GCHQ, rather than back to Washington, for analysis. In the late 1940s and early 1950s, GCHQ retained primary responsibility for areas such as Eastern Europe, the Near East and Africa. This period also saw the development of spheres of influence. For example, relations with Norway were an American responsibility, while relations with the Swedes belonged to GCHQ, although this demarcation was not strictly adhered to. GCHQ enjoyed the benefits of a panoply of bases provided by Britain’s imperial and post-imperial presence. Although the empire was shrinking, the very process of retreat often rendered the new successor states more willing to grant limited base facilities to the departing British. These facilities seemed innocuous, being termed ‘communications relay facilities’, but the reality was often different. Many countries, such as Ceylon, were unwitting hosts to GCHQ collection sites. Island locations, including Britain, were intrinsically attractive because they would be slower to be overrun by the enemy in wartime military operations.

  In the 1950s, Anglo–American relations were made easier in the Comint field by the arrival of the National Security Agency (NSA), which imposed some order upon the squabbling of the US armed services. In 1952 the Brownell report had recommended to President Truman the creation of a strong centralizing force. The three separate American armed services fought a desperate rearguard action against the creation of the NSA. General Samford of US Air Force intelligence denounced ‘strong central control of the national COMINT effort’ as a ‘major error’. He also warned darkly about Comint slipping away towards civilian control under the office of the Secretary of Defense. But Truman’s mind was made up and the NSA began to reshape American Comint. The efforts of the NSA to extend its control over electronic intelligence (Elint), the interception of electronic signals like radar, and to ‘fuse’ it with Comint processes would be more troubled and stretched on into the 1960s. American officials often envied the more centralized British model.

  The closest Anglo–American intelligence relationship during the immediate postwar period was probably that developed between RAF intelligence and the US Air Force. General Charles Cabell (later Deputy Director of the CIA) was head of US Air Force Intelligence as the USAF became fully independent of the US Army in 1947–8. While establishing an expanded intelligence organization and getting to grips with being a fully independent service, the Americans found RAF intelligence to be an ideal partner. RAF intelligence was headed by the convivial Lawrie Pendred, who was anxious to cement the Anglo–American relationship. This growing friendship also reflected the fact that GCHQ had identified air power as a critical area for Sigint, especially those arcane forms of Sigint associated with strategic bombing. Sigint in the air was one of the major growth areas of the early intelligence Cold War.

  Air intelligence was keen to develop Elint. It was invaluable for the operational planning for air attack against the Soviet Union. It was equally invaluable to anyone planning peacetime ‘spy-flights’ over Soviet airspace and looking for gaps in Soviet radar cover. Thus, in this area, air intelligence collectors were also consumers, not least to protect the security of their own missions. Elint was first developed by the Allies in the face of radio-guided German air raids during the Second World War and was later sited at the Central Signals Establishment at RAF Watton. Towards the end of the war, it continued to be refined against Japan.

  Initially, the RAF was ahead in this new field. By 1947 a fleet of specially equipped Lancaster and Lincoln aircraft patrolled the East German border, monitoring Soviet air activity. This was complemented by a programme of monitoring of basic low-level Soviet voice traffic by ground stations at locations such as RAF Gatow in Berlin. British ‘Ferrets’ began their first forays into the Baltic in June 1948 and the Black Sea in September 1948. In that year they began to be supplemented by American prototype B-29 Ferrets flying missions from Scotland to the Spitzbergen area. B-29 Ferrets were also supplied to the RAF under the Mutual Assistance Act from 1950. By 1948 much of the perimeter of the Soviet Union was covered. A British undercover team was operating in northern Iran, monitoring Soviet radar in the Caucasus as well as Soviet missile tests at Kasputin Yar on the edge of the Caspian Sea. The team conducting this wa
s posing as archaeologists, a favourite British cover for intelligence work.

  The Comint and Flint effort against the Soviet Air Force and associated strategic systems was one of GCHQ’s key areas of achievement in the first postwar decade. The arrival of the first Soviet atomic bomb in 1949 may have eluded them, but its subsequent operational deployment certainly did not. During the early 1950s the Joint Intelligence Bureau in London and the USAF target intelligence staffs had been busy exchanging sensitive data on ‘the mission of blunting the Soviet atomic offensive’. This involved the early counter-force targeting of Soviet nuclear forces in the hope of destroying them on the ground before they could be used. Senior officers in London had given particular attention to this matter because of the vulnerability of the UK. The Americans were impressed by the ‘considerable progress that London had made on the counter-atomic problem’. GCHQ and the RAF had amassed ‘a significant amount of evaluated intelligence, particularly in the special intelligence field, which would be of the greatest value’. Most of the airfields and the operational procedures for Soviet strategic air forces in the European theatre had been mapped by 1952. The full Anglo–American intelligence exchange in this field was somewhat ironic given the different views held in London and Washington on nuclear strategic issues at this time. However, full intelligence exchange on targets continued regardless.

  Between 1956 and 1960 several ‘incidents’ reverberated upon intelligence-gathering from seaborne and airborne platforms. In each case ministers in London reacted more strongly than their counterparts in Washington, constraining the nature and frequency of subsequent operations. For the practitioners, this underlined the value of working with allies. In the late 1940s and early 1950s the British had been more relaxed about forward operations, such as over-flights, and had passed their dividends to Washington. After 1956 the situation was reversed. London’s hesitancy in the face of various flaps and shoot-downs accelerated the shift of momentum in the world of Sigint towards the United States.