GCHQ. Richard Aldrich
the scale of Soviet activities and ambitions in the region, helping to trigger robust counter-pressure by President Truman.[8]
How the main target lists for sigint were drawn up was of central importance. In theory, they were created by the JIC. However, much of the preliminary work was undertaken by more shadowy committees working under the London Signals Intelligence Board, Britain’s supreme sigint authority. These enjoyed strong military input. When diplomats complained that political and colonial subjects were not getting enough attention, they did not get an enthusiastic response. Many felt that undue weight was being given to defence priorities, and to nuclear warfare in particular. The overwhelming emphasis given to defence had profound implications for the shape of British sigint. It accelerated the development of a revolutionary new kind of sigint that focused on equipment and military formations.[9]
During the Second World War, Bletchley Park’s primary emphasis had been the interception of communications signals for intelligence purposes. However, as the war progressed, there was growing interest in another kind of sigint that was derived from intercepting electronic signals, such as radar, which had been developed during the Second World War. A related field of interest was the growing use of radio waves to create missile guidance systems. Examining these enemy radio signals was known as electronic intelligence, or ‘elint’. Elint revealed a great deal about enemy weapons, and was also essential for conducting ‘radio warfare’, which involved jamming enemy signals and radar. The first example of this had been the successful efforts of Professor R.V. Jones to divert the beams used to guide the German bombers attacking London. These techniques were refined during the war against Japan. An elaborate elint unit was set up within Mountbatten’s South-East Asia Command under the improbable cover name of the ‘Noise Investigation Bureau’. In the summer of 1945, elint-equipped aircraft called ‘ferrets’ patrolled the night skies over Rangoon listening to Japanese radar.[10] Elint and radio countermeasures, conducted jointly by GCHQ and special units of the RAF, were a massive growth area after 1945, partly because they were so closely linked to strategic weapons. One great advantage of elint was that it rarely required the reading of complex enemy codes.[11] Increasingly, the business of signals intelligence would consist of two branches, the familiar one of communications intelligence or ‘comint’ and the new one of elint.
Britain had excelled in the use of both comint and elint during the Battle of Britain, and later in bombing raids over Germany. One of the architects of this system was Arthur ‘Bill’ Bonsall, who would become Director of GCHQ in 1973.[12] This success had made a deep impression on American intelligence officers in Europe, who felt admiration and not a little envy.[13] In early February 1945, the US Army Air Force held a conference of all senior air intelligence officers (A-2s) across Europe, at which ‘every A-2 expressed his disappointment at our utter dependence on the R.A.F.’ in sigint matters. The US Ninth Air Force had deployed some very effective converted Flying Fortresses as airborne listening stations, but the British had controlled the flow of strategic sigint. The lesson was clear. Colonel Robert D. Hughes, Director of Intelligence for the Ninth Air Force, told Washington that he wanted his own air sigint units with control over sigint policy and sigint research: ‘We feel that you should demand, and organize under your control, for peace as well as war, an organization similar to that of the R.A.F. … Unlike other highly technical forms of intelligence, in which our American Air Forces have shared, we have continued to depend entirely on the R.A.F. for this level of work in “Y”.’[14]
Elint formed one of the closest parts of the Anglo–American sigint relationship during the immediate post-war period because it focused on the Soviet military target. Exchange on elint was not initially linked to the Allied sigint agreements reached at the end of the war, but in 1948 it was being brought within the growing body of Western intelligence pacts that formed UKUSA. GCHQ approached Washington with a proposal to ‘extend the present British–US Comint collaboration to include countermeasures, intercept activities and intelligence’ in the field of elint. This meant coordinated patterns of ‘ferret’ flights – effectively a division of labour – with the resulting intelligence being swapped ‘via Comint channels’.[15] By the 1950s, GCHQ had achieved control over elint in Britain, and so was managing relations with all the various American outfits in this field. This had meant redrawing GCHQ’s charter to include not only comint but also elint, something which had not pleased everyone. R.V. Jones, who was Director of Scientific Intelligence at the Ministry of Defence in the early 1950s, strongly resented losing this part of his empire; the benefits of having all activities superintended by GCHQ were nevertheless overwhelming.[16]
Anglo–American sharing was important, because elint was an expensive business. Many of the target Soviet signals were short-range and could only be collected from ‘ferrets’, which were effectively flying intelligence stations. 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 ground stations at locations such as RAF Gatow in Berlin listening to basic low-level Soviet voice traffic. British ‘ferrets’ made adventurous forays over the Baltic in June 1948 and the Black Sea in September 1948. Remarkably, they were soon crossing Iran to reach the Caspian Sea, thus flying perilous missions close to the very heart of the Soviet Union.[17] On the ground, a British undercover team was also 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. The team conducting this work were posing as archaeologists, a favourite British cover for all sorts of intelligence work. Once a week they drove from the Iranian border with the Soviet Union to the British Embassy in Tehran to deliver their precious tapes.[18]
Early Western elint efforts in the air were spurred on by the knowledge that the Soviets had launched their own secret ‘ferret’ programme. In April 1948 an American radar station in Germany reported that it was being probed by ‘ferret’ aircraft, and in November a Soviet plane circled a US radar station at Hokkaido in Japan collecting signals for an hour, and then escaped without interception due to bad weather. Defectors also brought tantalising snippets. In May 1948 Baclav Cukr, General Secretary of the Czech Air Force Association, escaped to the West bringing knowledge of a group of Dakota-like planes at Zote airfield outside Prague. These mysterious aircraft were kept under constant guard in special hangars, and had ‘several special antennae on the outside’, a sure sign that they were elint collectors.[19]
During the war the vested interests of many different RAF commands had made it difficult to create a single coherent elint organisation.[20] Post-war rationalisation allowed the fusion of these elements. RAF Watton in Norfolk was selected as the new home of elint, and collected the remnants of many wartime units into 100 Countermeasures Group.[21] The result was a weird menagerie of aircraft which were one-off flying laboratories adapted for various special tasks. The mainstays were twenty ageing Handley Page Halifax bombers. There were also B-17 Flying Fortresses, Lancasters, Mosquitoes and Avro Ansons, together with an Airspeed Oxford and a Percival Proctor. The unit at Watton soon received some new Avro Lincolns, effectively updated Lancasters. All were stuffed with unique items of electronic listening equipment and primitive wire recorders for collecting voice traffic.
Christened the Central Signals Establishment, or ‘CSE’, Watton boasted a Signals Research Squadron, a dedicated sigint unit known as Monitoring Squadron and a Radio Countermeasures Squadron. The Avro Lincolns were the best aircraft available, and they were given over to radio countermeasures and radar jamming, since they would have to work closely with RAF bomber formations in any future war with the Soviet Union. The Lincolns would soon be fitted with the revolutionary new carcinotron, or ‘backward wave oscillator’, in effect an electronic gun that produced powerful microwaves of the same frequencies used by radar, giving them enormous onboard jamming power. By contrast, some of the other airframes used for listening were antique. However, it was a venerable Halifax from Monitoring Squadron that was despatched on sigint collection duty over the Soviet Zone of Germany during the early stages of the Berlin Blockade in 1948. This was the first sign of a possible ‘hot war’ between East and West, and GCHQ decided it was time to share the lessons of sigint more widely. For the first time lectures on radio countermeasures and tactical sigint were given to officers passing through the RAF Staff College at Bracknell. A handbook on tactical sigint was prepared for all staff officers, albeit no mention was made of