The Secret Listeners

by Sinclair McKay

  But the fact was that the Cairo listeners and the cryptographers were largely under the aegis of MI8, and of Bletchley Park too. This was not just a matter of concealing from the enemy that you had tapped into his radio signals, for he would assume that you had done so. It was a matter of concealing the fact that you had then either decrypted his messages on site in Cairo, or sent those messages, in their impenetrable codes, back to Bletchley Park, where they had been unlocked. For any commander to act on information gained thereby, the source obviously had to be concealed, or faked.

  Internal tension was therefore inevitable. There were occasions when the military accused the codebreakers of ‘holding back’ vital information concerning German tanks; the Heliopolis station vehemently denied doing any such thing. Then there were the unsubtle accusations that the station personnel were behaving almost like spoiled children. ‘I have had a series of periodic wails about a shortage of staff . . .’ declared one military memo. ‘It is difficult to be moved by the story of the hard work being done at Heliopolis. Other “Y” troops are working just as hard in the field, and under most uncomfortable conditions. Heliopolis still finds time for its vague and long letters.’ The memo concluded saltily: ‘If Jacob would stick to co-ordinating the crypto work of the three Sections and leave it at that, things would be easier. No-one questions his crypto ability.’

  But then one day in 1942 came the panic-stricken evacuation of the British operatives from Cairo to Palestine, and it was noted that, for those who had been in the city for any length of time, news of the move – caused by Rommel’s seemingly ineluctable progress – came as a heavy blow. The day became known as ‘Ash Wednesday’, when, in the face of the Afrika Korps’ advance, GHQ in Cairo burnt all vital documentation and the ashes of so many secret documents formed billowing clouds in the air. Harold Everett’s wry observations turn a scene of undignified panic into something closer to Keystone Kop comedy:

  Ash Wednesday – the famous day on which the British Embassy burnt its secret papers and showered ashes on Cairo is well known, but running the embassy burnings a close second was the incineration that took place at the School [Heliopolis]. Every piece of paper on which there were any indications that intercept was the School’s ‘business’ was to be burned. I was one of a group of NCOs entrusted with this task. I burned paper until I was up to my ankles in ash and had succeeded in burning my mini-puttees. Others armed with india-rubber were ordered to erase all call-signs or other revealing graffiti that was written on walls, tables or chairs. An unfortunate few were detailed to the latrines to remove, if necessary, any secret waste which, contrary to standing orders, had been used as toilet paper.

  We were somewhat cheered up in our task by a rumour that the electrically obsessed captain had given himself a shock trying to dismantle some of the wiring which had so fascinated him. Every sign of our existence was to be expunged. Like Baloutha the walls were to be left desolate.4

  According to another Cairo officer, Lieutenant-Colonel Sayer, who later that year wrote a long letter – now held in the National Archives – on the subject, it was quite an achievement to keep the Y Service properly operational during the crisis. ‘The “flap” was terrific, with “evacuation” the slogan,’ he wrote, adding sardonically:

  Many an awkward file must have disappeared in the holocaust, which became one of the jokes of Cairo. Our plan was simple. To get away as much of our ‘Y’ resources as we could, so that we could build up and start again somewhere else. While order followed order, we quietly slipped across the Canal . . . B sections, a large part of the Special Wireless Group . . . this lot made me feel that, if the worst came to the worst, we could get going again in Syria or Iraq in next to no time.

  The subsequent embarrassing evacuation of Cairo – embassy staff, refugees, escaped politicians from Greece – sounds, from Harold Everett’s account, extraordinarily chaotic. There were scenes of confusion and distress at the railway station as a disparate population of expats were corralled on to trains for destinations such as Gaza in Palestine. Sayer, in an informal dispatch sent back to London, subsequently contrived to see the lighter side of it:

  Sarafand [in Palestine] was standing room only. Most of 5 IS got parked in the camp of a Weapon Training School, where they ate the bread of idleness for many days. Then the O.C. School decided that it would be good for them to have some training in bayonet fighting. And they had to do it. This was one of the more humorous incidents.

  He was also robustly rude about a couple of the female Y Service operatives, who ‘have an enormous sense of their own importance, although they haven’t produced anything worth fourpence since east Africa. Well, they were told one morning that all women employed by the Army were to be temporarily enrolled in the ATS in order to facilitate control during evacuation . . .’ But these women, according to Sayer, had their own condition to lay down: that they be enrolled automatically as captains. ‘Imagine it, mon cher . . .’ wrote Sayer to his unnamed correspondent. ‘Rommel bowling gaily towards Alex[andria]; the smoke of the burning GHQ papers clouding the sky . . . and these two damn women arguing that their positions in 5 IS would be jeopardised if they were evacuated as privates ATS and not officers.’

  Having been informed by the First Secretary at the Embassy that her association with King Farouk was unsuitable, ‘cipherine’ Barbara Skelton herself left Egypt, and found herself in Jerusalem. ‘After buying some Syrian silk stockings,’ she wrote of her introduction to the city, ‘I boarded a car loaded with Wrens who never stopped chattering about their mothers’ dogs, other Wrens’ young men or dances. The driver and I exchanged desperate glances.’

  But she took to the city, and to Palestine, very quickly. Indeed, it seemed to come as something of a relief to her sensibilities. She admired the strong-looking women with baskets of fruit on their heads, and even the healthy-looking donkeys, which she compared favourably to their ‘wiry’ Cairo counterparts. Overall, she found much more colour here, even in the occasional bad meal, with fish that tasted ‘like drains’. The idyll was not to last; a matter of weeks later, while she was sunbathing in Haifa, a ‘very dilapidated’ bus with the word ENSA stencilled on it drew up; the drivers assumed that she was an ENSA girl and as a result, they drove her all the way back to Cairo.

  Even in the aftermath of the chaos, there were more uplifting moments in Cairo; one such was the trapping of a German spy, who had been operating with an illicit aerial, some poor counterfeit currency, and codes deriving from Daphne Du Maurier’s Rebecca. Wireless intercept operators were able to pick up the spy’s lame transmissions and in the end, he was cornered on a boat by a British major. The spy tried to escape by throwing a ‘grenade’ which turned out to be a pair of rolled-up socks. Sometimes it is difficult to know with the Abwehr whether such gambits were purposely bathetic.

  In terms of security, British communications back home appeared to be reasonably watertight, though there were doubts, precisely because of the intense secrecy, that the military top brass in the desert were getting the full benefit. Because the work of Bletchley was known only to a very few in Whitehall, Ultra information had to be parcelled out in ways that obscured its source. In mid-1942, Churchill himself instructed the head of MI6 to make sure that the full text of two German situation reports was sent to General Auchinleck, so that he could be in no doubt that he had access to genuine intelligence, as opposed to what he might have seen as suppositions from various agents. Bletchley Park until that point had been careful to paraphrase such information to muddy the source; after this, according to the Bletchley official history, they were more relaxed about sending precise messages – though in the summer of 1942, as Rommel’s eastwards rampage continued, these were of limited value.

  The difficulty was that although the messages were being decrypted, interpreting them was another matter; and Rommel was adept at disguising his plans and misdirecting his enemies. Thus, just before the Battle of Gazala in May 1942, even though his forces – the artillery,
the tanks, the divisions – could be heard massing via the build-up of radio traffic, no one among the British could work out how these were to be deployed. Rommel’s messages were so carefully couched that even once the code was broken, the terms he used remained elliptical – a challenge that no codebreaker can surmount without direct access to the relevant glossary of code terms – and his plans could not be immediately divined.

  Rommel had one other hugely useful secret weapon at his disposal; the Germans were in receipt of decrypted messages sent from the US military attaché in Cairo back to Washington DC. As a result, during the Battle of Gazala, the Germans were rather better informed than the British. The British fought back fiercely, forcing the Germans on to the defensive for a time, with heavy losses on both sides; but Rommel counter-attacked, and the British were forced on to the back foot and ultimately had to retreat from Gazala. And now Rommel’s forces advanced inexorably upon the Allied positions at Tobruk, creating carnage. Here, however, Bletchley Park and the Y units were able to provide a constant stream of Enigma decrypts; possibly thanks to these, the British Eighth Army retreated in time. Nonetheless, Tobruk surrendered. Rommel was made a field marshal. Allied anxiety was profound: were Rommel’s seemingly unstoppable forces on the edge of seizing Egypt? In June, the British had created a new line at El Alamein; Rommel’s intention was to smash right through it.

  However, in one of those smoke-and-mirrors reverses that seem to characterise the intelligence world of Bletchley and the Y Services, the intercepts eventually picked up messages showing that Rommel had been reading the US military attaché’s reports. One particular dispatch stated that the British were pretty much beaten; this in turn led Rommel to believe that now was the right time to take the Nile Delta. It is thanks to decrypts from the Y Services at Heliopolis and Bletchley that the British, in turn, were able to note Rommel’s plans and predict the date of his assaults.

  In fact, the interception services were getting sharper; it also helped tremendously that in August, Rommel’s field Signal Intelligence Unit was captured, leaving his forces a little vulnerable. The exhausted General Auchinleck was replaced by the then Lieutenant-General Bernard Montgomery, and just days after he took command, a crucial Enigma message was decoded; it was, broadly, an outline of Rommel’s attack plans. The line at El Alamein was strengthened, while Montgomery encouraged even greater fluidity in the flow of Y intercepts and Bletchley intelligence to the front, asking that reports be shorn of jargon so that they could be understood by all those who needed to see them.

  Thanks to these decrypts and interceptions, Montgomery was able to build up a brilliantly accurate picture not merely of Rommel’s land forces, but also of the air power being mustered between the Germans and the Italians. When at the end of August Rommel’s fresh advance was launched, the British forces knew exactly what to expect, and countered it expertly. ‘During Rommel’s attack in August, we had him “taped” the whole time,’ wrote Lieutenant-Colonel Sayer in a letter back to London in November. ‘The El Alamein line gave us our first chance to use Loop D/F.’ Direction finding with a loop aerial was to prove especially effective at picking up the sources of enemy transmissions. ‘It was immensely valuable.’

  The Germans drew back; and at this point, the desert war started to turn decisively. Decrypts and intercepted messages showed within a couple of days that Rommel was concerned about his lines of supply, and about the transport losses the Afrika Korps had suffered before its retreat. This intelligence allowed Montgomery the breathing space he needed to put his forces through ever more intensive training. The work of Heliopolis and Cairo had given Montgomery the opportunity to plan with much greater effectiveness, even in the face of pleas from Whitehall that he should go on the offensive before Rommel had the chance to summon stronger defences. The Second Battle of El Alamein would come just a few weeks later – a battle in which the Y Service was to operate at the very peak of its power.

  As the USA finally entered the war in December 1941, with her forces materialising throughout 1942, the question of just how much the British could share of the secrets of Bletchley Park was raised. It was not merely a matter of pooled intelligence; there was again the altogether more vital question of security. Even by this point, very few people outside Bletchley Park knew the extent to which the codebreakers had been taking the Enigma codes apart. And no matter how staunch an ally the US was, there was an understable initial hesitancy when it came to sharing their deepest confidences.

  But from the start, Bletchley’s relations with their counterparts in the US military were friendly, and there was a great deal of mutual respect; respect that was not often mirrored in political circles. And as a small party of Americans were inducted into the secrets of Alan Turing’s bombe machines – the advanced electrical contraptions, standing eight feet tall, at Bletchley and its associated out-stations, that crunched through potential Enigma permutations at industrial speed – so too was US command taking a strong interest in the way that the British had organised its Y Service. And much as the military forces were fighting side by side, there was interest in setting up American Y bases on English soil. Early in 1942, the Y Committee invited Captain Brown of the US Army Signals Corps to take an overview of the entire operation, from Hampshire all the way to Mombasa. His subsequent report, lodged in the archives, makes for fascinating reading – he was especially impressed with the thoroughness of the training that each of the new recruits was put through. ‘At the conclusion . . . the students are given a practical exercise,’ he wrote. ‘Linguists, log readers and check clerks’ would be assembled:

  [Then the] background of a certain military situation is explained to all concerned and the exercise begins. From messages intercepted on the headphones and operation orders delivered by ‘dispatch riders’, the syndicates are expected to deduce the enemy intentions and report them to the instructing officer . . . Misleading and irrelevant messages are interposed between those containing valuable information and this information is in turn given sometimes in terms which should be obvious to the dullest intellect and sometimes in a more subtle or indirect form. ‘Noises off’ such as of dive bombing and shell fire are introduced into the microphone in an attempt to simulate active service conditions as closely as possible.5

  What impressed Captain Brown particularly was the care with which each recruit was selected and graded before being assigned to particular Y Service duties; from dexterity with complex messages, to the ability, in battle situations, to screen out the tumult and focus in the face of disorientation and danger, on the signals coming through. All this required both special techniques and special character.

  It should be remembered that the US military at that time lacked the breadth of experience in wireless interception that the British had gained. And so Captain Brown concluded by recommending that ‘the American Signal Intelligence Service maintain the closest contact and co-ordination with the British Y Service to the end that our units may be quickly trained to penetrate the complexities of the German system’.

  But there were still delicate security considerations – and matters of diplomacy – for the Y Committee to debate. Any American listening base established in Britain would be passing its material both to Bletchley Park and to US headquarters in London. The Americans wanted a prime site at which to train their own secret listeners; the Y Committee felt that the base already established at Trowbridge in Wiltshire might be ideal. In the archival memos of the Y Committee, we see a fascinating – and fleeting – deference shown towards the British. The Americans were happy to tug at the sleeve of MI8 to ask advice on such matters as the security implications of sending raw material via teleprinter. And MI8 was also on hand to help out with ‘suitable lists’ of call signs and frequencies.

  In fact, the amount of hand-holding that went on in the early stages now makes for charming reading; just as Y Service operatives such as Pat Sinclair and Marjorie Gerken were later to be amused by the influx of American personnel, with th
eir hilariously direct ways, so the British authorities were pleasantly helpful, especially when it came to smoothing ruffled feathers. One such case involved the proposed US listening site in Trowbridge; in order for them to move in, the British company already there, headed by Colonel de Cros, would have to be shunted out. The Americans were anxious that MI8 do the talking to de Cros; they thought it would sound better coming from them. The British were happy to oblige.

  A few weeks later, though, it turned out that, for technical reasons, Trowbridge was not what the Americans were after. Could they instead move to another base they had had their eye on – Tidworth? Again, the Y Committee was pleased to be of service. But the novice Americans were in turn anxious not to cause offence. Pleased with British offers that training officers be sent out to the US to bring operatives there up to speed, they were equally keen not to cause diplomatic strains regarding the destination of their intercepted signals; the Americans’ Colonel Bicher informed the Y Committee that of course all traffic should be sent through to Bletchley Park, and that everything would be done to ensure that the Americans and the British did not simply end up duplicating each other’s work. It was the start of a beautiful friendship; one which, in the aftermath of the war, would become uneven and strained.