Most Secret War

by R. V. Jones

  The rocket parts with the courageous Pole arrived at Hendon on 28th July, but he could speak no English, and he refused to let anyone see the parts until he had authority from one of the only two Polish officers in Britain whom he knew. One was General Bor, and the other was a Polish colonel. He sat on his sack, and drew a knife whenever one of our Intelligence Officers made any move towards it. This scene continued for some hours, reaching peaks of embarrassment whenever he wished to fulfil one of his natural functions, while we searched for the General and the Colonel. One of them, I think that it was the Colonel, was either ill or out of London, and finally we had to get the General himself to come along and tell our gallant Pole that it was alright for him to talk to us and show us his treasures.

  He endeared himself to us by telling us that had the Russians not advanced, he had organized enough of the Polish Underground Forces to try to capture Heidelager, and so gain all the information that we wanted. This was now going to be impossible, but he still wanted to get back. He told us that he reckoned he could stay in London about three weeks, but that was about as long as he thought that he could leave his organization. He explained that he had left quite a good man, a colonel, in temporary charge. He had previously told us that he himself was only a corporal.

  One item of information that he gave us was that the rockets often exploded high in the air, and that the Germans were very annoyed when they did so. It turned out that this fault had only been recognized after the firing range had been moved to Poland; the rockets fired from Peenemünde had carried bags of dye which coloured the sea on impact, and until the move to Blizna this was the only evidence that the Germans had of how and where the rockets had fallen. As we had predicted, after the Peenemünde raid Hitler himself had ordered the rocket trials to be transferred from Peenemünde (about the beginning of September 1943, according to General Dornberger in his book V-2) and as soon as firings from Blizna were started at the end of 1943, it became clear that something was wrong at the far end of the trajectory. It took the Germans a long time to discover the cause; one of the fuel tanks appeared to be exploding. This was partially prevented by lagging the tanks with glass wool but, as Dornberger said, ‘it was not until the closing months of the war that we found the final solution by reinforcing the front of the hull with riveted sheet steel casing’.

  The arguments in Whitehall concerning the weight of the rocket lasted throughout July and well into August. Herbert Morrison was near panic: on 27th July he was wanting the War Cabinet to plan immediately for the evacuation of a million people from London—he had already tried on 11th July to have our Invasion forces diverted to land in the V-1 launching area. But I was beginning to get near the truth as regards the weight of the warhead for, based on what I had told him, Lindemann wrote to Brendan Bracken on 1st August, ‘The intelligence evidence such as it is indicates one ton or a bit more. The more pessimistic scientists say this is impossible, they themselves, they claim, could make a rocket of the desired characteristics carrying five to seven tons.… The answer seems to me that none of them so far as I know has ever made a rocket that flew at all.’

  More information was coming in from Normandy, where we had captured many of Oberstleutnant Beger’s papers, and where we found one of his storage sites at a quarry at Hautmesnil, between Caen and Falaise. In the tunnels there, we actually found a great white wooden dummy rocket, which had clearly been used to give the troops experience in handling the missile around the bends in the tunnels, and I have sometimes wondered what would have happened had we found this dummy earlier, since Lord Cherwell had for a long time contended that what we had been photographing at Peenemünde in 1943 were simply dummies left out in the open to hoax us. But before we found the dummy, we also found the trolleys on which the genuine rockets were to be supported, and one of these was sent back to Farnborough. There again, some of our experts saw it, and immediately complained that I had misled them because the curvature of the supporting cradle was much less (4 feet 8 inches) than I had stated the diameter of the rocket to be. The experts took this opportunity to reduce their weight estimates accordingly, but I telephoned Farnborough and asked them to take a second look at the cradle because I was sure that the diameter of the main body of the rocket was about 5 feet 7 inches, as we had said. The discrepancy could be explained if, by bad luck, what had been sent back was one of the cradles supporting the rocket not somewhere along its main diameter but on a reduced diameter nearer the nose-cone, in which case I would expect the inner surface of the cradle to be chamfered to match the slope of the nose-cone. Someone at Farnborough went off and looked, and came back to report that the chamfer was indeed there, and they had previously failed to notice it. Even so, the experts did not put their weight back to their earlier estimates, but brought it down to 24 tons.

  To Charles Frank, Bob Robertson and me, the naïveté of our ‘experts’ was incredible. They were all eminent, some very eminent, in particular fields of science or technology, and yet they were completely out of their depth when dealing with the rocket. I can remember a Fellow of the Royal Society, for example, saying at one of the meetings that he was amazed at the accuracy with which the Germans would have to set the rocket before launching it. He had calculated the angle to which the rocket would have to be tilted in order to give it maximum range, and found that this was only half a degree off true vertical. If it were fired vertically upwards, it would of course fall back on the heads of those who had fired it, and so the whole of the range was determined by this small angle off vertical, which would have to be very accurately determined. What he had in fact calculated, quite possibly correctly, was the trajectory of a rocket fired, as on 5th November, with a stick attached, and launched in the familiar way from a bottle, where the rocket gradually curves over in its trajectory under the influence of gravity. Almost in chorus, Bob, Charles and I shouted out, ‘gyroscopes!’, because we knew that the Germans were using gyroscopic control, with information about the attitude of the rocket being transmitted via servo mechanisms to graphite rudders that were placed in the main jet so as to deflect the stream of incandescent gases and thus turn the rocket on to a pre-set trajectory both in bearing and in elevation. We had known this and reported it ever since the Ultra traffic on Blizna became available, because it contained reference to ‘Strahlrüder’ which, as far as we could translate it, meant ‘jet-rudder’: it was a basic invention that made advanced rocket technology possible. As we explained the system, our scientist looked Heaven-wards and said, ‘Ah, yes, gyroscopes! I hadn’t thought of them!’ And that was about the level of the better contributions from the experts.

  By 6th August, a week after they had given the weight as 24 tons, they said that this figure would now be the upper limit. I myself thought this would still be an overestimate, and I decided to look at all the available evidence over again. We had had many reports about prospective weights come through our Intelligence system, but many of these had been coloured by the mishandling of the system from the time the panic had started in April 1943, and it was almost impossible to assess the reliability of individual reports, and to allow for the fact that many of them may have been feeding back to us information which had unwittingly been provided in previous briefings. I therefore decided to accept only those reports which had mentioned liquid air or liquid oxygen as one of the fuels. This provided a touchstone, since it showed that any report which mentioned it had at least one element of truth, and might therefore reflect the knowledge of someone who had had a fairly direct contact with genuine information.

  The effect of applying the touchstone was remarkable. Out of the many reports on our files it selected only five, as follows:

  Date Origin Length Diameter Total Weight Fuel Weight Warhead

  15.2.44 Agent 14 m — 7 — 1 ton

  22.2.44 Agent 12 m 1/1½m 11/12 tons 8 tons 2 tons

  3.4.44 Agent 12 m 1½m 11 tons 8 tons 1 ton

  21.5.44 P/W 1 more

  than

  9 m 1½m —
— 1, 1½ tons

  2.8.44 P/W 1 16 m 1½m 8 — 1 ton

  They all pointed to much lower weights both for the rocket as a whole and the warhead in particular than those favoured by the experts. The last report had come from the interrogation of a prisoner-of-war, and Charles Frank and I went out to Latimer, the Interrogation Centre, to see him. Talking things over with Charles on the way back, I said—as we went round Shepherd’s Bush—that I was now prepared to call everyone else’s bluff, and declare for a rocket of 12 tons all-up weight with a 1 ton warhead. I was the more ready to do so because there were references in the Ultra traffic between Peenemünde and Blizna to items called ‘elephants’ which normally weighed one ton, and which, as far as I could tell, seemed to be something in the nose of the rocket. If these were warheads shaped to fit into the slender nose-cone, they might conceivably suggest an elephant’s head or trunk. There was also mention of a material called ‘A-Stoff’ for which the normal requirement for a rocket was 4.3 tons. On the assumption that this was liquid oxygen, and that another main fuel, ‘B-Stoff’, which might be a liquid such as alcohol, was involved, the total fuel weight would probably be around 8 tons.

  I informed Sinclair, Portal and Cherwell as soon as I had come positively to the conclusion regarding the weight of the warhead, on 6th August. The question now was: how should I make my statement more widely to secure maximum effect and to show up the follies of calling in men who were certainly experts in their own fields, but as regards Intelligence were utter novices compared with Charles and me? The opportunity presented itself almost immediately for, despite having been deposed by Inglis, I was still a member of the Prime Minister’s Crossbow Committee, and its next meeting was at 6 p.m. on 10th August. Inglis was not a member of the Committee, but Easton was now there, to speak instead of me, and the meeting was rather more crowded than usual, so that it was possible for me to sit so that I was not easily visible from the chair. This I wanted to do, because there was a delay in Churchill’s appearing; Herbert Morrison explained that the Prime Minister had been held up, and that he was to take the chair in the meantime. I particularly wanted to make my statement about weights in Churchill’s presence, and so I sat as obscurely as possible through the first half-hour or more of the meeting, in the hope that he would ultimately appear. But, as luck would have it, he had had an urgent call to go out to Italy, and as time went on it became clear that he would not be taking over the meeting. At last, someone remembered that I should be there, and asked for my comments on the statements of Easton and Charles Ellis, the Scientific Adviser to the War Office. The former’s statement was limited and factual, the latter’s conjectural, and trying to excuse some further lowering of the expert estimate of the weight of the rocket in the last week because the diameter was now known to be 5 feet 7 inches instead of 6 feet. Even so, the weight was still around 20 tons. So I then gave my own figures of about 12 tons total weight with a one ton warhead, which met with a generally incredulous reception, and the Committee’s minute ‘took note with interest of the above statements, but recorded their view that it was too early to draw a firm conclusion regarding the smaller size of the warhead of the rocket’.

  The following morning Cherwell telephoned me and told me that he was very worried on my account, because I had made such definite statements about the weights, when he himself could not see how such a large rocket could possibly be so light. He added, ‘They are all waiting for you to make just one mistake, and I am afraid that you have made it now!’ He advised me to provide myself with a correcting statement which would allow me some loophole of escape, but I told him that I had done as honest a job as I could in assessing the evidence, and that all I could say was that the weights that I had stated were what the evidence pointed to. He then told me that he was going later in the day to look at the pieces of the Swedish rocket which were now at Farnborough, and which the Establishment were trying to reassemble. On the visit he was accompanied by Edward Wright, who had formed a friendship with him when Wright was a Student of Christchurch. After Farnborough, they went on to Oxford for the weekend.

  On his return, Wright told me that the Farnborough reconstruction had vindicated what I had said. The only trouble was that they could not make the weight of the warhead more than about 1,300 to 1,500 lbs., compared with the one ton with which I had surprised the Crossbow Committee. By this time I was so sure of the weight that Frank and I went to Farnborough the next day to look at the warhead for ourselves; it was an odd experience now to have to convince the Farnborough experts that their estimate was too low, having had only a few days before to argue with the Whitehall experts that their estimates were much too high. The Farnborough estimate depended on the piecing together of the rim of the warhead at its wider end, i.e. the end further away from the nose. This was in several segments, and I managed to show the Farnborough engineers that there was a segment missing which, if they had included it, would have increased the size of the cone significantly; when they made the appropriate correction, the warhead weight came out at 2,000 lbs.

  A sidelight on the vehemence with which the battle of the warheads had been waged has been provided by Professor W. W. Rostow, the American economic historian who in the 6o’s became Special Assistant to the President of the United States. As an American Army Air Force officer he had been assigned in 1943 to British Air Intelligence, and was asked by Sir George Thomson, the Scientific Adviser to the Air Ministry, to examine the arguments on both sides regarding the weight of the warhead. Having talked to me in, as he says, my ‘marvellously dishevelled office’. he then listened to those who believed in the ten-ton warhead and finally called a meeting of both sides. ‘Although,’ he wrote, ‘I was at that time relatively young (27), I had acquired some experience with both academic and government bureaucratic structure and their capacity for bloodless tribal warfare. But I had never been present at, let alone presided over, a meeting with more emotional tension than that centred on the size of the V-2 warhead.… What emerged was a reasonably solid Intelligence case for a one-ton warhead.

  ‘I concluded that the evidence Jones had mustered was essentially correct; called on Sir George Thomson and informed him of my conclusion: the warhead would be about one ton. He looked up at me with a twinkle in his eye and said: “You are a lucky young man. A few days ago a V-2 mis-fired from Peenemünde and landed in Sweden. We flew it back in the bomb bay of a Mosquito. We have now measured the venturi. Obviously it could not develop more thrust than that required for a one-ton warhead.” After some exchange on the curious way that essentially rational problems of intelligence and science could generate emotional attachments of great strength, I departed.’

  As for the heights to which emotions could rise, I had received a warning shortly after the meeting of 18th July, when I had alarmed Churchill by telling him that I thought that at least a thousand rockets had been made, based partly on my recognition of the rocket on the Blizna photograph. A few days later Inglis showed me a letter that had been sent to him by Douglas Kendall, one of the Chief Photographic Interpreters at Medmenham, protesting that I had told the Prime Minister that I had found the Blizna rocket, and that I ought not to have done so before I had asked Medmenham to confirm my observation. This was clearly a sore point for, having missed the rocket on the Peenemünde photographs, the Medmenham interpreters had now missed it at Blizna. It would never have occurred to me to criticize them for this, for I regarded myself as a fourth phase interpreter to supplement what had been done in the first three phases of interpretation at Medmenham, and I had the advantage of being in closer touch with other forms of Intelligence, of necessity, than the normal interpreters were. It was hard enough to be criticized by Duncan Sandys and his Crossbow colleagues on the one hand for withholding information, and on the other hand by the interpreters for giving it out prematurely, but when the criticism, as in the latter case, came from friends, who in their letter to Inglis described me as an amateur interpreter (and added that what I had seen on the
Blizna photograph was more probably a locomotive), this was a warning that feelings were getting out of hand. I told Inglis that the best thing would be simply to acknowledge the letter but that in the interest of good relations, I would not reply and reprove them, as I could have done, for once again missing the rocket.

  A fortnight or so later they provided me with an opportunity for a riposte. Evidently stung by the fact that they had not detected the rocket, they scanned the Blizna photograph again for signs of the launching equipment for the rocket. Actually, this involved no more than a platform of wooden railway sleepers, and even concrete was unnecessary—General Dornberger indeed deplored the waste of effort that had been involved in making concrete platforms in France. A prisoner had told us that to protect the wooden platforms from the flame of the rocket jet during the first few seconds a conical deflector was placed below the rocket to deflect the hot gases sideways. Our experts elaborated this slightly by suggesting that the device would have four pads arranged at the corners of a square, on which the tail fins of the rocket would rest. The resultant structure would look something like a large lemon squeezer, and so it was called (it can be seen in Plate 28(c) mounted at the tail of the rocket on its trailer). The dimensions stated by the prisoner were somewhat increased by the experts, and somehow between them and Medmenham ‘feet’ got transposed into ‘metres’, so that the squeezers instead of being 3 to 4 feet high became 3 to 4 metres high. Medmenham therefore looked at the Blizna photographs for such objects, and quickly found them. They then produced an urgent interpretation report, No. BS780 announcing their discovery.