Category A VERTICAL EMPIRE

Governments tend to make the announcements of the cancellation of a project as brief as possible. The Opposition and the Press will not follow up the cancellation of a project such as Black Arrow unless there is the whiff of a scandal. The Press was not interested; and in this case there was very little that the Opposition could use to attack the Government.

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One group of people that is rarely informed of the true reasons for the cancellation are those who work on the projects, and whose livelihood depends on them. Not surprisingly, urban legends or conspiracy theories begin to emerge. The cancellation of Black Arrow was no exception.

Engineers are usually conservative by nature, and often Conservative by political inclination. One of the ‘bogey men’ of the time was Tony Benn (known earlier in his career as Anthony Wedgwood Benn, but who had now adopted a more demotic name), and to those who worked on the project, part of the mythology was that it was cancelled by Benn and the socialists, when it was actually cancelled by a Tory Government!

In reality, virtually all the opposition came from the Treasury, as the following memo from February 1969 illustrates:

I have no doubt that the Cabinet will give overwhelming approval to the Ministry of Technology’s [Tony Benn] proposals for Black Arrow. At the S. T. meeting on Friday, 21st February, all Ministers from all Departments except the Treasury were not only in favour of the proposals, but emphatically so. The reservations of D. E.A. officials [Department of Economic Affairs] are not apparently shared by D. E.A. Ministers, including Peter Shore. The least enthusiasm was shown by Sir Solly [Zuckerman, Chief Scientific Adviser to the Government], but he gave qualified support and clearly did not brief the Lord President to oppose.

2. I should in fairness add that Tony Benn put his case very attractively. It clearly has some merit and while I suspect there may be a considerable degree of optimism influencing the supporters of Black Arrow, I doubt if the Treasury arguments however skilfully deployed, will sway other Cabinet members.

3. In the circumstances I would suggest that a last ditch fight by the Treasury against Black Arrow in Cabinet could be mistaken. It might undermine the Treasury’s general position on more hopeful causes. I feel a tactically more rewarding line would be for you and the Chief Secretary to say that having looked at the proposals you feel that there is merit in them (including the proposal for a British launcher) and that you do not propose to object.20

The Ministry of Aviation had been subsumed into the Ministry of Technology in February 1967. It was further reorganised with the advent of the Conservative Government lead by Edward Heath in 1970, becoming part of the new Department of Trade and Industry (DTI). But after all the attacks on Black Arrow by the Treasury, it was actually the Aviation department of the Ministry of Technology which began the process by which Black Arrow would be cancelled. The memo in question is undated, but seems to have been written around October 1970:

As I mentioned the other day, I feel there might be considerable advantage in arranging an impartial examination of the National Space Technology Programme in the light of the recent Black Arrow launch failure [the R2 launch].

It is of the utmost importance that the next firing of Black Arrow, currently scheduled for May 1971, should be successful. We, RAE and Industry are already engaged in analysing the technical causes of the failure, but we have to recognise that there are also wider implications. Another failure, and our national technological competence as well as the future of the National Space Technology Programme would be in question. Examination of the programme as a whole by an outsider of suitable qualifications could be useful in ensuring that it develops from this point on in the best possible way.

The examination would have to take as a starting point an acceptance of our primary objective in space, which is to attain the capability in satellite technology enabling us to offer space hardware, internationally and on an industrial scale. The investigation should in addition not question the broad institutional framework of the Programme-in other words it would be accepted that the effort was a joint Government and Industry one. Within these constraints, however, the investigation should be given the widest possible remit to examine the means we have employed to reach our objective.

The formal terms of reference might be on the following lines:-

To assess the relevance and appropriateness of the Programme, in its present form, to the goal of establishing a significant national competence in satellite technology.

To study in particular the role of the national launcher (Black Arrow) in the programme; the level of effort needed to develop it into a dependable vehicle; and the cost of alternatives to it.

To report on the management of the Programme, with special reference to the launcher element.

And to make recommendations.

I believe that an examination along these lines could be of a very real help to us, especially in providing the answer to two questions — is the level of spend on the Black Arrow launcher programme a sensible one, or ought it to be increased very substantially in order to achieve real gains; and, whatever the level of sensible expenditure on a national launcher programme might be, would it be preferable and more economic to use an American launcher?

The difficulty, of course, is to find a man of sufficient managerial and technical qualification within the UK who was not already involved in the space programme. We are already separately engaged in the discussion of suitable names. My present purpose is therefore to seek your approval of the terms of reference set out above, on the basis of which we might approach a suitable candidate.21

The question was who among what have been termed as ‘the great and the good’ would be willing and available, although one stumbling block was the requirement for some technical knowledge. In the event, an impeccably qualified candidate was identified and, on 1 October 1970, accepted the invitation to undertake the inquiry: William Penney.

William Penney is best known for his work on Britain’s atomic weapons, although he had many other scientific accomplishments to his name. He won a scholarship to study at the University of London, winning the Governor’s Prize for Mathematics and graduating with First Class Honours in 1929. In 1944 he joined the British mission to Los Alamos, working on the use of the atomic bomb and its effects. On his return to England, he was put in charge of the British atomic bomb project, and saw the project through to the test of the first bomb in 1952. At this point Penney was offered a Chair at the University of Oxford. Always more inclined toward the academic life, he was keen to accept this post, but he was persuaded that the ‘national interest’ required him to continue as director of the AWRE at Aldermaston until 1959. From 1954 Penney served on the Board of the Atomic Energy Authority, becoming Chairman in 1964. He retired as Chairman in 1967, and then became Rector of Imperial College.

Given these achievements, it was unlikely that his findings would be disputed, and given his expertise in running demanding experimental programmes, he would have seemed to be the ideal man for the job. Being retired from any form of Government research meant he had no axe to grind, and would be widely seen as an impartial observer.

A briefing note for the Minister after Penney had submitted his report noted that:

Lord Penney’s approach to his inquiry was informal. By meeting the people in industry and government concerned with Black Arrow, and discussing the project with them, he aimed to make personal assessment of the management of the programme at the same time as briefing himself on the details of the project. He made two visits to industry, to see the major Black Arrow contractors – British Hovercraft Corporation on the Isle of Wight, and Rolls-Royce at Ansty, Coventry. He visited RAE Farnborough on two occasions, and had a number of discussions with the staff of space division and other headquarters divisions with an interest in Black Arrow. For details of the alternative launchers to Black Arrow he relied on information supplied by the department: he made no visits abroad in the course of the inquiry.

As might be expected, the report was thorough and comprehensive, stretching to 24 pages and 68 sections. He fulfilled his brief admirably, looking at Black Arrow and its alternatives, then considering the viability of Black Arrow within the larger framework of British space policy. His conclusions and recommendations are worth quoting:

My conclusions are as follows:

The disappointing performance of Black Arrow launcher R2 in September 1970 was not due to poor project management, bad fundamental design, or low grade effort. We know we were taking a gamble in trying to make do with so few test launches, and the gamble went against us.

The cost of launching of the X3 satellite on the R3 vehicle is almost fully incurred, and the best policy would therefore be to launch X3 in July 1971 as planned. But in spite of all the work being done to follow up the R2 failure, we cannot be sure that the gamble will not go against us again on R3. The Ministry has neither the time nor the resources to build up greater confidence in Black Arrow before X3 is ready for launch.

It is probable that with the present launch rate of one Black Arrow a year, we will still not be fully confident of its reliability by 1974 when we are planning to launch X4, the second major technological satellite. Even if the Ministry agreed to fund an increase in the launch rate, only one or two extra Black Arrows could be built and launched by 1974.

There is a three-year gap between X3 and X4, but Black Arrows are being built at the rate of one a year. This mismatch between the production rates of launchers and worthwhile satellites may well continue beyond X4, and cannot easily be remedied by adjustments to the launcher programme which is already running at about the minimum level for efficiency…

The current programme gives us too few Black Arrows to establish the vehicle as a proven launcher in a reasonable timescale, and too many to meet our requirements for satellite launches. It is therefore not a viable programme at present, and there is no easy way out of the dilemma.

And on the subject of alternative launchers, he notes:

Black Arrow has no alternative use, and the nation would have much to gain and little to lose if it were cancelled in favour of American launchers. We would be abandoning a certain political independence and a guarantee of commercial security payments, but on these two points satisfactory safeguards should be available from the US authorities.

Unless a formal approach is made quickly to the inhabitants on the availability of Scouts and other launchers for our technological satellite programme, further commitments will have to be made on Black Arrow vehicles as an insurance move.

As soon as we are satisfied that we can get the launchers we need from the Americans on acceptable terms, the Black Arrow programme be brought to a close as soon as possible. However, the launching of X3 on the R3 vehicle should proceed, and there may be a need for a further launch if problems arise with X3/R3.

I therefore recommend that:

The Ministry should make a formal approach to the US authorities as soon as possible about the availability of launchers for X4 and subsequent satellites in the National Space Technology Programme, and terms on which they can be provided.

Commitments on R5 and subsequent Black Arrow vehicles should be kept the minimum possible level while the Americans are being approached, and all work on them should be stopped as soon as satisfactory arrangements have been made for the supply of US launchers.

The X3 satellite should be launched as planned on the R3 Black Arrow vehicle in July 1971; the R4 vehicle should be completed in all major respects and used as a reserve for R3 up to the launch.

If X3 goes into orbit successfully and functions as planned, the Black Arrow launcher programme should be brought to a close without further launches.

If X3 fails to go into orbit successfully or fails to work in orbit, the Ministry will have to decide whether to bring the launcher programme to a close at that point or repeat the X3 experiments by launching the X3R on the R4 vehicle. Unless they are sure that the R4 vehicle has a better chance of success than the R3, and it is worth spending кШ million to repeat the satellite experiment, a further launch should not be sanctioned.

The X4 satellite should be launched on Scout; and Scout or Thor Deltas should be bought as necessary for later satellites in the series.

The Ministry should determine at a high level the views of British industry on the value of a technological satellite programme. If no such value can be identified the programme should be brought to a stop. If it is established that the programme is worthwhile, a plan should be drawn up for a series of future satellites so organised as to give the maximum benefit to British firms in their attempts to win contracts in the international market.22

It is difficult to argue with his conclusions, or, indeed, with his recommendations. As he correctly points out, there was a ‘mismatch between the

production rates of launchers and worthwhile satellites’. Making fewer launchers was not economic; there were not the resources to make more satellites.

The report was submitted to the Minister in January 1971, and made its way up the government hierarchy, culminating in a meeting held in the Prime Minister’s room at the House of Commons at 5:15 pm on Monday 6th July, 1971.

Those present were the Prime Minister (Edward Heath), the Chancellor of the Duchy of Lancaster (Geoffrey Rippon), the Lord Privy Seal (Earl Jellicoe), the Secretary of State for Trade and Industry (John Davies), the Minister for Aerospace (Frederick Corfield), the Chief Secretary to the Treasury (Maurice Macmillan), and Sir Alan Cottrell, Chief Scientific Adviser. An excerpt from the minutes of the meeting reads:

The Lord Privy Seal recalled that on 24 May the Ministerial Committee on Science and Technology had approved the proposals by the Minister of Aerospace that the Black Arrow programme should be stopped, that we should support the full development of the X4 satellite and that for the launching of small satellites we should in the future rely on the American Scout launcher. The Prime Minister had been doubtful about the impact of this decision on future European collaboration in science and technology, particularly as the French were developing their own launcher the Diamant. Since then however the political difficulties have largely dissolved. The Diamant programme had now been deferred and the French were themselves using the Scout launcher this year.

The Prime Minister and the other Ministers present agreed that the proposals originally approved by the Science and Technology Committee in May should now be implemented. The Chancellor of the Duchy of Lancaster said he did not think that the cancellation of Black Arrow would be deemed inconsistent with anything the government had said when in opposition; there had been no commitment to back any project which was not successful.

The Minister for Aerospace said he thought that the announcement of the decision would not cause great surprise and could be done by an Answer to an arranged Written Question.

The Prime Minister agreed to this and suggested that the announcement should be as late as possible.23

Three weeks later, the following exchange appears in Hansard for 29 July 1970:

National Space Technology Programme

Mr. Onslow asked the Secretary of State for Trade and Industry what progress has been made with the review of the National Space Technology Programme; and if he will make a statement about the future of the Black Arrow Launcher.

Mr. Corfield: The first phase in the review of the National Space Technology Programme has now been completed. Plans to launch the X3 satellite on a Black Arrow vehicle later this year have been confirmed, but it has been decided that the

Black Arrow launcher programme will be terminated once that launch has taken place.

We have come to this decision on Black Arrow mainly because the maintenance of a national programme for launchers of a comparatively limited capability both unduly limits the scope of the National Space Technology Programme and absorbs a disproportionate share of the resources available for that programme.

We hope to complete our review in the early months of 1972. Meanwhile work is continuing in industry on research into basic satellite technology and on the development of the X4 satellite. X4 is planned to be launched in 1974 on a Scout vehicle to be purchased from N. A.S. A.

The curious (or perhaps not so curious) feature of the announcement is how little attention it received. True, Black Arrow always had had a low profile, but neither in Parliament nor in the press was there any great comment. Perhaps the last word should be given to the New Scientist magazine, which had this to say in August 1971:

Despite considerable success with small launchers – notably Skylark – the modern sport of rocketry evidently rouses little excitement in British hearts. The now- promised demise of the Black Arrow programme, the erstwhile Black Knight venture, is unfortunate only because its death throes have been so prolonged. Announcing last week that, after a final launching later this year when it hopefully will put the X 3 satellite into orbit, Mr Frederick Corfield, Minister for Aerospace, said that henceforth Britain’s need to pursue experiments in space technology would be met with US launch vehicles. The reason essentially is that nearly all foreseeable space applications are going to require satellites in high geostationary orbits; Black Arrow falls far short of this requirement, being able to lift some 260 lb only into a near-Earth orbit.

One measure of the effectiveness of a rocket motor or fuel combination is Specific Impulse or S. I. One way to define it is (thrust x burn time)/(total mass of fuel burnt). Another way is the thrust obtained from each lb (or kg) of fuel burned each second.

In modern units, S. I. would be quoted in Ns/kg – which turns out to be dimensionally equivalent to m/s. This is because S. I. can also shown to be the same as the exhaust velocity of the gases from the combustion chamber. Furthermore, the final velocity of a rocket (in the absence of gravity, air resistance and so on) can be shown to be:

vfinai = vexhaust x ln(mass at start/mass at end)

Hence the greater the exhaust velocity, the greater the final velocity of the rocket (ignoring all the complications such as gravity, air resistance and so on).

The difference between the mass at the start and the mass at the end is effectively the mass of fuel (unless anything is jettisoned along the way!). The skill of the designer is to build a vehicle as structurally efficient as possible – all fuel and no structure is not possible, but the structural mass must be as small as possible. Blue Streak had an unusual tank structure, being a lightweight stainless steel ‘balloon’, which needed to be constantly pressurised to keep its structural integrity. Black Knight and Black Arrow were also structurally very efficient.

The equation above only applies in ideal circumstances. The effectiveness of a rocket motor is decreased in the atmosphere, since the thrust from a rocket engine derives from the pressure difference between the pressure inside the combustion chamber and the pressure outside. In a vacuum there is no outside pressure. Another way of looking at this is to say that the exhaust velocity is reduced by the air outside. Thus S. I. is sometimes quoted at sea level and sometimes in vacuum. Vacuum S. I. is typically 10-15% higher than sea level.

The HTP/kerosene combination has a relatively low S. I., around 210-220 at sea level. Oxygen/kerosene gives an S. I. of around 245 at sea level. Hydrogen/oxygen is the most effective combination of all, some motors reaching S. I.s of at least 400. One way of looking at this is to say that there is double the thrust for the same weight of fuel.

The saga of the warhead is a story in itself. The urgency with which it was pursued is slightly puzzling in hindsight since it was not intended to deploy Blue Streak until the mid-1960s. The UK had taken the decision to develop thermonuclear devices (also known as fusion weapons or more popularly, the H bomb) in 1954, and the Atomic Weapons and Research Establishment (AWRE) at Aldermaston did not as yet have a working design. Given all the other development work that needed to be done, a decision on a warhead could have been deferred until a fusion weapon had been developed. There was a degree of risk in this: there was the possibility that no warhead could have been developed within the weight limit of one ton. On the other hand, the Blue Streak design was the largest possible for a single stage vehicle with only two motors. Designing anything larger would have led to a very unwieldy weapon.

What Britain did have was a relatively low yield lightweight fission device – Red Beard – and a design for a much more powerful warhead which incorporated fusion principles, but was not what would now be called a thermonuclear device. This was Green Bamboo – never tested, since it soon became obsolete. The snag was that this device had a weight in the region of 4,500 lb, but in the absence of anything else, it was Green Bamboo which was specified in OR 1142, entitled ‘Warhead for a Medium Range Ballistic Missile’.

Red Beard, the lightweight fission weapon, had been ruled out since its yield was only 10-20 kilotons (kT), and given the predicted accuracy of Blue Streak, this was thought to be inadequate. Green Bamboo was too heavy. Thus William Penney, then Director of Aldermaston, was asked if a lighter warhead of similar yield could be built. He replied to say this might be possible, but that ‘the figures of 1,800 lb weight and 30” diameter quoted for an unboosted fission bomb with a yield of about 1 megaton were purely estimates at this stage and could not be guaranteed.’4 After further study, he decided that ‘on current knowledge I could not guarantee to make a satisfactory warhead within the weight specified’. A weight of around 2,200 lb was more probable, and it would use around twice as much fissile material as Green Bamboo. It would be a pure fission device, but in the absence of any alternative, this warhead, now codenamed Orange Herald, was chosen, and, punctiliously, the wording of the OR was changed from ‘thermonuclear’ to ‘megaton’. (Note: there is some ambiguity here. ‘Megaton range’ meant around a megaton yield, and 600 kT would qualify since 600 kT = 0.6 MT, which can be rounded up to 1 MT.)

Given that the lightest warhead that AWRE could guarantee would weigh 2,200 lb, this decided the issue of one motor or two for Blue Streak: if it was to reach the range required it would need two motors.

A memo concerning Orange Herald sums up the position with some rather interesting comments along the way:

Orange Herald – OR1142

Your loose minute of 31 October asks what is the present status of the official requirement for Orange Herald, and whether the Minister knows of the project. I propose to answer in some detail for I think that it will be useful to record the history of the project.

2. A Draft Operational Requirement No. OR1139 (May 1955) for the Ballistic Missile was discussed at an Air Ministry Operational Requirements Committee meeting on 9th June, 1955. … In discussion of the range of the missile a warhead weight corresponding to Green Bamboo was assumed, and it seemed unlikely that the range which Air Staff desired could be met by a single-motor missile…

4. In the meantime, however, CGWL had been discussing with AWRE the penalties implicated on the missile design by the weight of Green Bamboo, and DAWRE [Director AWRE, William Penney] had said that he could develop a megaton warhead of about half the weight, although requiring more fissile material.

5. This smaller megaton warhead was considered by AWRE to be an important project, and in mid August I was asked by AWRE to arrange for an MOS [Ministry of Supply] code word to be registered for it, for AWRE use and to facilitate inter­departmental discussion. One copy of my minute notifying the choice of a code word for “A megaton warhead for the Medium Range Ballistic Missile” went to PS/Minister [the Minister’s Private Secretary] but, of course, without any description of the warhead

7. In discussion on 14th October, DDAWRE [Deputy Director AWRE] made it clear that AWRE consider it important to go ahead with the lighter warhead, that they are in fact doing so (for the present on their own initiative) and that they are considering the possibility of a trial in 1957. AWRE’s line is thus quite clear …

9. I have also consulted the CGWL side, in the person of DGGW [Director General Guided Weapons]. He tells me that they are not yet in a position to put up the missile requirement OR1139 for the Minister’s approval prior to acceptance: they still consider the project to be in the design study stage, and a meeting will probably be held in December (1955) to make a final assessment. It seems almost certain that a twin-motor design will be agreed, but whether the missile has one or two motors, they will still want the lighter warhead. I pointed out that Orange Herald has at the moment the status of a private venture on the part of AWRE, and that it seemed to me desirable that an OR should be issued to cover it. So far as DGGW is aware, the Minister has not been given any data from the CGWL side on the characteristics of

Orange Herald.

10. Thus the answers to your questions are:

(a) The present status of Orange Herald is that of a private venture by AWRE, for the present Air Staff Requirement for a warhead for the OR1139 missile refers specifically to Green Bamboo. DGGW will inform Air Staff that the missile needs a lighter warhead; this should result in a revised OR calling in effect for Orange Herald, and we can then clear with AWRE the warhead parts of this OR in readiness for the eventual submission of 0R1139/1142 to the Minister by CGWL and CAW [Controller Atomic Warfare].

(b) There is no evidence that the Minister knows anything of the project beyond the code word and its definition.

[Sgd] D. CAMERON DAW Plans. (10th November 1955)

That last line is worth repeating: ‘there is no evidence that the Minister knows anything of the project beyond the code word and its definition’. Decisions involving the expenditure of millions of pounds were authorised not by the politician in charge of the ministry, but by the senior officials running the projects – and Orange Herald probably cost close on ten million pounds (as much as Black Knight or Black Arrow) to design, build and test. Indeed, it is rare that ministers were involved in anything other than the basic decisions. Mention is made of the OR being subject to final ministerial approval. It would be unfair to say that this comprised a ‘rubber stamp’, but on the other hand, how was a professional politician able to judge whether the OR made sense or not? Ministers would take decisions on matters such as whether a ballistic missile was needed, and the rest was up to the permanent officials. Ministers do take the final responsibility – thus when Blue Streak was ultimately cancelled as a weapon, ministerial reputations were at stake. Indeed, it might be said that Duncan Sandys’ defence of Blue Streak while Minister of Defence and Minister of Aviation, even though it was his job to do so, probably hindered his future career. This memo does throw some light on the degree to which decisions involving very large sums of money are taken quite independently of the minister who is nominally in charge – and yet, in almost any system of government, this is the case.

Orange Herald was, in many ways, an extremely unsatisfactory device. It required a very great deal of weapons grade U235 – one Air Ministry paper gives a figure of 120 kilograms, although other figures have been quoted. Whether the UK had the facility to produce 60 such warheads is a very interesting question. Another memo noted that ‘Orange Herald is one of the rounds to be tested at Grapple next year. The cost of the material may be £2% million.’ If those costs were carried through to the final deployment, then the warhead cost would be 60 x 2% = £150 million!

Operation Grapple was a series of tests of atomic devices based at Christmas Island in the Pacific. Three devices were scheduled for the first series, held in mid-1957, and Orange Herald was the second. The first and third were attempts at fusion devices, which were not wholly successful, but showed ‘proof of principle’. Grapple had been described by the British Government as ‘H bomb’ tests, and the press reported the Orange Herald test as an ‘H bomb success’. Orange Herald was not an ‘H bomb’, but rather a large fission device, although one can understand why the Government did not draw attention to this. This has led some later commentators to suggest the deception was deliberate – that if the fusion tests had not worked then the Government could always claim success via the Orange Herald test, whose yield was around 720 kT.

Although as we will see, Orange Herald was never deployed in its original function as Blue Streak warhead, it did come into service in a rather indirect way. The fusion tests later in 1957 were successful, but there was still a long way to go between the testing of the ‘physics package’, as the part that goes bang is sometimes called, and deployment of a fully serviceable weapon with all its handling and safety devices. Mainly for political reasons, a high yield warhead was required for the V bombers so that the Government could say the RAF had a ‘megaton capability’. The answer was a reduced yield (400 kT) version of Orange Herald, codenamed Green Grass.

Initially, the warhead was mounted in the casing of the original British atom bomb, Blue Danube, and the resultant weapon named Violet Club. Owing to the large amount of fissile material (U235) in the warhead, there were some very considerable operational limitations. Any mishandling of the device which caused it to become damaged might result in sufficient fissile material coming into contact so as to cause a low level explosion. One safety device used to prevent this happening was several hundred ball bearings, which filled a void inside the warhead and physically kept the fissile material apart. If Violet Club had ever been flown operationally (which is unlikely), the ball bearings would have had to be removed before take-off. A later version was produced in a different casing (Yellow Sun Mk 1) which allowed the ball bearing to be jettisoned in flight! The number of Green Grass warheads produced was quite limited, partly due to the amount of fissile material needed, and, given the constraints with which the weapon had to be handled, the RAF was quite glad when it was replaced by a fusion warhead.

The testing of Orange Herald meant that RAE could now move on with the design of a re-entry vehicle for Blue Streak, but to do so meant that AWRE had to supply details of the warhead in terms of masses and dimensions. Little was forthcoming, until a slightly indignant memo in May 1958 from the Deputy Director at RAE noted that

… it was learned that no work was in progress on Orange Herald at AWRE, nor was there any intention of doing any. Newley suggested that our work, based on Orange Herald, should be stopped, and that AWRE would offer instead a two-stage warhead of similar weight… Orange Herald had very doubtful in-flight safety, and is highly vulnerable to R effects, and the new proposal is welcome in that it would be greatly superior in both these respects. Nevertheless, it seems to have emerged in a most casual fashion.5

The ‘R effects’ mentioned refer to a perceived vulnerability of warheads to neutron irradiation. Orange Herald, with its large amount of U235, would have been very vulnerable to such effects.

The two-stage device referred to would be some variation on the fusion weapons that had been tested at Grapple. These went under the generic code name of ‘Granite’ devices (e. g. Green Granite, Purple Granite etc.). Hence the RAE, who was responsible for the re-entry vehicle, dropped their work on Orange Herald, and waited in anticipation for details of the size, shape and weight of the new Granite devices.

There then followed one of the greater ironies of the British nuclear weapons programme. Nuclear co-operation with the United States had ceased soon after the end of the war, and Britain had gone it alone in the development of firstly a fission device and now a fusion device. In many ways, the achievement was quite remarkable, as Aldermaston, with its relatively small budget and limited resources, produced a working fusion design less than three years after work had begun. As a result of Aldermaston’s success, the Americans agreed to resume nuclear co-operation. The UK was given the designs for two nuclear warheads, one of them being the Mark 28, approximate yield 1.1 MT. The advantage to the UK was that the design had been fully engineered as a weapon rather than just as an experimental device, and so the Granite designs, painstakingly developed by Aldermaston, were dropped in favour of the Mark 28. The anglicised version of the Mark 28 would go into service as Red Snow.

The major problem to continuing with ‘weaponising’ a Granite design was that further nuclear testing would have been required, and public and world opinion was turning very much against atmospheric nuclear tests. Britain did not have an underground testing facility, and so the advantages of adopting the American design were that much greater. Hence if Blue Streak had been deployed operationally, then the warhead would have been the 1.1 MT Red Snow.

Whatever the warhead, it seemed that its weight would not come under a ton, which imposed its own restraints on the design. Thus Air Vice Marshall Satterly wrote in July 1955:

My views are that if we go for the single motor missile we shall always be in trouble over weight and range, and will find ourselves in the early 60’s [sic] still striving to catch up. Let us be bold and go for the twin motor and exploit any future saving in weight in the warhead, or anywhere else, by increasing the range. Let us then review the position in a years [sic] time, when we can put much more reliance on the small warhead and when we are due to consider parallel development of a second missile.6

Sir Steuart Mitchell, CGWL, ‘reluctantly agreed that two motors would probably be necessary to guarantee a range of 1500 nautical miles’. Dr William Cook, Deputy Director at Aldermaston, said that AWRE ‘had not realised how significant was the weight of the small warhead in reaching this decision.’ Reluctantly, given the uncertainties in the payload, it was realised that two motors would be needed to achieve the necessary range. A single motor missile would have been almost identical to the American Thor missile, but the heavier UK warhead coupled with the already limited range of Thor (1,500 miles with the US warhead) ruled out the use of Thor by the UK. This was summarised in a paper by Sir Frederick Brundrett, Chief Scientist at the Ministry of Defence, in June 1956:

The co-operation between the Americans and ourselves on this missile development is extremely good except that which is limited by United States laws governing the passage of information on atomic weapons. We have, in fact, considerably more knowledge on this subject than we are supposed to have and it is vitally important that the Americans are not made aware that we have the information that follows.

The warhead for Thor is being designed to a weight of atomic core of 1,500lb, but the weight of the warhead itself must include the metal sheathing designed to act as a heat sink. The total weight including this sheathing will be 2,600lb if the sheathing is of steel and 3,100lb if the sheathing is of copper. The comparable figures for our own design are 2,250lb, 3,600lb and 4,500lb…

What this means, however, is that if an arrangement could be made for the Americans to provide vehicles to which we could fit our heads, which is a technical possibility, the range of the American vehicle with our head would be reduced to something of the order of 1,100 miles…1

There is no doubt that the single motor design would have been simpler, cheaper, and would have taken less time to develop, but, in a sense, the Air Ministry had painted themselves into a corner. The missile had to be as big as it was to achieve a range of 2,000 miles with a megaton warhead. But no one appears either to have queried this requirement or even decided what the missile was for. Was it a deterrent? Was it actually intended as a weapon that could be used to win a war? Did it need a range of 2,000 miles? The Strath Report, also concluded in 1955, looked at the effect on the UK of just five megaton warheads, and was deeply pessimistic about the result. And if the intention was to ‘win’ a nuclear war with the USSR, how much destruction would have been necessary to annihilate it or, at least, force it to surrender?

The requirement could have been relaxed either in terms of range or warhead – and it does seem odd that no one ever contemplated the possibility of warheads becoming lighter. And given the range as 2,000 miles, why did it have to be a megaton warhead? Would 200 or 400 kT have been sufficient? And could Aldermaston have designed such a warhead within the new weight constraints? Further, the payload weight was pushed up by inadequate knowledge of the re­entry head. It might have been worth putting more research into re-entry before finalising the design. It is possible that a single motor design might have had a better chance of ultimate deployment, being smaller, cheaper and quicker into service. But the assumptions on which the criteria were based never seem to have been questioned in depth.

Europa was a three-stage vehicle (the Perigee Apogee System of Europa II was sometimes claimed as a fourth stage), the first stage being a modified Blue Streak, which had an overall length of 60 ft 4 inches (18.4 m) and a diameter of 10 ft (3.05 m). The take-off mass was 197,500 lb (89.4 tonnes), which included

126,0 lb (57 tonnes) of liquid oxygen and 56,300 lb (25.5 tonnes) of kerosene fuel. At the first stage engine cut-off, the mass remaining, including residual propellants and tank pressurisation gas, was 15,200 lb (6.8 tonnes).

The liquid oxygen was held in the upper tank, which was a pressurised shell without stringers or frames, constructed of welded stainless steel sections with a minimum thickness of 0.019 inch (0.48 mm). The kerosene tank was also of stainless steel but strengthened with internal frames and stiffeners and external longitudinal stringers. The two tanks were separated by a deep domed diaphragm built up of welded segments, and similar domes closed off the top and bottom ends of the tank assembly. The liquid oxygen tank was fitted with anti-slosh baffles.

The propulsion bay was attached to the tanks by a short cylindrical skirt structure which was designed to transfer the thrust loads to the tanks above. In the propulsion bay were two thrust beams from which the rocket engines were gimballed, and the ends of these beams, as well as transmitting the thrust loads, acted as support points for the vehicle in the launcher stand. The bay was of light alloy construction, and housed the combustion chambers, the propellant pump assemblies, the engine control systems, as well as the hydraulic pumps and servo – jacks for swivelling the combustion chambers. The bay was closed at the rear end by a heat shield to keep out exhaust gases and radiant heat from the rocket exhausts. Two panniers were placed on either side of the propulsion bay to house more equipment and instrumentation.

There was initially considerable technical discussion – and controversy – as to the best way to design the tanks, which were the major structural element, and the one where most weight could be saved. It was realised that the high internal pressure – about two atmospheres – required to avoid cavitation at the propellant turbopump inlets could be used to stiffen up a very light structure so that it could take heavy longitudinal and bending loads. A pressure of 30 psi over a 10 ft diameter circle represents a total force of 340,000 lb, which was quite adequate to accelerate upper stages of around 35,000 lb to an acceleration of some 7-8 g.

The liquid oxygen tank was put forward of the kerosene tank in order to bring the centre of gravity as far forward as possible with respect to the centre of pressure, so as to ease the task of the control system. A lighter kerosene tank structure could be obtained if some of the end loading were taken by stringers and frames, since the mass of the liquid oxygen tank under acceleration would need excessively high pressures in the tank.

The choice of tank material, too, was the subject of considerable study, both light alloy and stainless steel being close contenders. It was essential for the tank material to have good strength at liquid oxygen temperature (-183 °C), to be able to withstand kinetic heating, to be readily and efficiently weldable, and be available in uniform sheets of closely controlled thickness. Stainless steel was eventually chosen, made by Firth

Vickers for railway coaches, and with very good physical properties over the range of temperatures required. Individual cylindrical sections were prefabricated from 36 inch wide strips of material.

The two Rolls Royce RZ 2 rocket engines each had a rated thrust at launch of

150,0 lb, giving a take-off acceleration of 1.3 g. The original thrust rating of the RZ 2 engine was 137,000 lb, and this was used for the single stage flights. The higher rating, obtained by an increase in combustion chamber pressure, was used in the later flights.

The turbines were driven by hot gases produced by fuel rich combustion of a small proportion of the main propellants in separate gas generators, and two turbopump units supplied the propellants to the regeneratively cooled thrust chambers. The bright yellow plumes produced from the gas generators can be seen very clearly as the vehicle lifts off. The total propellant flow rate was 1,210 lb/s for the two motors. At high altitudes, the thrust of an engine increases, due both to an improvement in specific impulse brought about by a more efficient expansion of the exhaust gases, and to increases in propellant flow rates as the hydrostatic heads at the propellant pumps rise with vehicle acceleration. Sea level S. I. was around 248, vacuum S. I. was around 285.

The main function of the pressurisation system was to provide pressure in the liquid oxygen tank to preserve its structural integrity, to provide sufficient pressure at the pump inlets to suppress cavitation, and to control boiling of the liquid oxygen. The pressurisation system operated in two principal modes: ‘standby’, with the tanks full of propellants, the pressure in the liquid oxygen tank was maintained at about 9 lb/in2 and about 5 lb/in2 in the kerosene tank; and ‘flight’, when the pressures were raised to 30 and 15 lb/in2 respectively, starting about one minute before lift-off. The ‘standby’ pressures were chosen to provide adequate stability of the vehicle under conditions of ground loading, winds, etc., and the liquid oxygen in its tank would be in a state of equilibrium boiling. For ‘flight’, a low-pressure vent valve on the liquid oxygen tank was closed, and the combined effects of atmospheric heat input and of nitrogen supply from the pneumatic control unit raised the pressure to flight level in about 30 seconds. During the raising of pressure in the liquid oxygen tank, the pressure in the kerosene tank was raised so that the differential pressure across the intertank diaphragm was maintained at a safe value. The engines were then started. During flight, internal supplies of gas were needed so that the pumps did not cavitate or the tanks collapse. This was done with two heat exchangers or evaporators, one of which used the waste heat in the exhaust gases from one turbine to provide gaseous oxygen for pressurising the liquid oxygen tank, using a feed from the liquid oxygen pump discharge. The other, associated with the other engine,
evaporated liquid nitrogen supplied from a storage bottle on the vehicle to pressurise the kerosene tank.

One distinguishing feature of the flight models of Blue Streak (and, later, Black Arrow) was the spiral painted around the vehicle, which can be seen in the photograph on the right. This was for the benefit of the cameras filming the launch, and was the brainchild of an Australian mathematician, Mary Whitehead. In an interview some years later, she had this to say of the pattern:

The zig-zag pattern on the Blue Streak – that was at my request, because we were required to know whether the missile rolled as it went off [the launcher]. There were, I think, three or four cameras – they were called launcher high speed cameras – around [the launch site], so with that pattern, if the rocket rolled you could measure it really easily, depending on where that diagonal was relevant to the top and bottom stripes.

I had seen the black and white checks that were used on other missiles. I think that might have been in America, and this was the same sort of thing. But making a continuous line like that, you could measure to a degree whether or not it had rolled: as far as I know, I don’t think they did.

The interstage skirt was a stainless steel corrugated truncated cone, 1.23 m high, tapering from 2.8 m to

2.0 m, which weighed 137 kg. A small solid fuel motor was used to separate the two stages: it provided a thrust of 40 kN for 2 seconds.

The design of the second stage, also called Coralie, was constrained by several factors. Its size was set by the weight that Blue Streak could carry, and Blue Streak had been designed as a ballistic missile, not as the first stage of a satellite launcher. The 2 m (approximately 78 inches) diameter was certainly wider than the planned 54-inch Black Knight stage, which had the advantage that the vehicle was less flexible. The original brochure design had only one motor: the four motor design made control easier, particularly in the roll mode, and also meant that the interstage structure could be shorter and thus lighter.

The stage had a mass of 1,850 kg, of which 9,850 kg were fuel (100 kg of this was left at burn out) – 6,440 kg of dinitrogen tetroxide and 3,410 kg of UDMH. The chambers were pressure-fed from a gas generator, which used 41 kg of dinitrogen tetroxide together with 18.5 kg of UDMH and 98 kg of water, the water being used to lower the temperature of the gases to 350 °C. The pressure in the tanks was maintained at 18.6 bar (the combustion chamber pressure was 13.7 bar). Each chamber had a thrust of 68.1 kN (15,300lb) and a burn time of 75 seconds.

There is no doubt that choice of pressurised tanks did make the stage structurally rather inefficient. The choice was made in part to save time – the French had had little experience with turbopumps. A gas generator was lighter than simply using compressed helium gas, and a similar system had been in use on the Veronique sounding rocket. In addition, the same gases were used to drive the steering mechanism for the chambers and to generate the on-board electrical power supply.

Attempts were made to test the stage separately, with a vehicle called Cora1. The Cora 1 version used only the French Coralie stage, while the Cora 2 version added the German Astris stage. The Italian Europa nose fairing was also tested. For these tests the rocket nozzles were shortened to allow sea-level operation and four fins were added for stability. In the event, only the Cora 1 version was tested, and this failed on two out of three attempts.

The interstage structure was a cylinder 1.23 m long with a mass of 137 kg. Separation of the third stage was by explosive bolts, which caused problems in some of the early flights.

The German third stage, also known as Astris, was powered by dinitrogen tetroxide and Aerozine 50, an equal mixture of hydrazine and UDMH. This was stored in a spherical titanium tank 1.2 mm thick. The helium gas was stored in two bottles made of glass re-inforced plastic pressurised to 300 bar. The main motor had a thrust of 22.5 kN and two small control chambers of 500 N thrust (in vacuum). Since the chambers were to run in vacuum, the pressure in the chambers was a relatively low 11 bar. For a small vacuum stage where a restart capability could be useful, a pressure feed had advantages over turbopumps. The all-up mass was 3,370 kg (7,420 lb) and the empty mass was 610 kg (1,340 lb).

Germany had, of course, been the world leader in rocketry up to 1945, but the diaspora of rocket scientists and technicians, coupled with the perceived militaristic nature of rocketry development, meant that no significant work had been done since. On the other hand, there are advantages in starting again from scratch. Some of the initial German ideas for the third stage were very ambitious, and design studies for a high energy stage were outlined by Dietrich Koelle of Bolkow at a European Spaceflight Symposium in May 1963 . The paper mentioned that ‘Since 1961 intensive studies have been carried out at Bolkow Entwicklungen concerning an optimised high energy stage OPMOS’.

The three designs were ‘based on the propellant combinations H2/O2 and H2/F2 pressure-fed, and H2/O2 pump-fed. The results of the studies indicate that the payload capacity of the ELDO launch vehicle can be increased by the

introduction of a high energy upper stage from the present 220 lb to some 1,550 lb for escape missions.’ The studies were not merely theoretical: ‘Small hydrogen cooled engines have been on test for some time at the firm of Bolkow’.

The motor chamber was also distinctly unusual. It would provide 8,650 lb thrust, and used an Expansion – Deflection nozzle, where the flow is expanded radially and then turned axially. It has the advantages that it is a good deal shorter than the conventional rocket chamber, as seen in the artist’s representation above, and also allows for a greater expansion of the exhaust gases.

Calling the PAS a fourth stage was perhaps overdoing things slightly, but it was designed to enable Europa to put a satellite into geostationary orbit. It was described thus by J. Nouaille, who was the Project Management Director, in 1968:

… A lower metallic skirt attaches the stage to the top of the Europa I third stage. At the upper part of this skirt a separation mechanism releases the PAS system from the third stage when appropriate.

Four small rockets fixed on top of the perigee motor, approximately in the plane of the centre of gravity of the PAS system, spin up the vehicle, as soon as separated from the third stage, to a velocity of 120 rpm.

The perigee motor is then ignited, giving the vehicle an increment in velocity of approximately 2,450 m/s.

The main characteristics of this motor are:

empty mass 70 kg mass of propellant 685 kg

specific impulse 278 s maximum pressure 61 bar

maximum acceleration 10.3g

After burnout of the motor, a second separation occurs between the empty spinning perigee stage and the spinning satellite.

During the whole of its operation, the perigee stage is controlled and monitored by electronic equipments attached inside the upper skirt of the stage (equipment bay).

Apogee Motor.

The apogee motor is part of the satellite. It is ignited by a telecommand order at the most appropriate moment, taking into account the actual orbit and attitude data of the satellite.

Its main characteristics are:

empty mass 36 kg propellant mass 156 kg

specific impulse 270 s maximum pressure 42 bars

velocity increment 1470 m/s approximately.

The launching procedure of the ELDO-PAS satellite… includes

(a) an injection from Guiana into a parking orbit by the three lower stages of the launcher: after burn-out of the third stage, the attitude of the vehicle remains controlled by a cold gas jet system installed on the third stage. The platform of the Inertial Guidance system is used as a reference during this phase. Ground stations in Kourou (Guiana), Fortalezza (Brazil) and Brazzaville (Congo) are used to monitor the vehicle.

(b) When crossing the Equator, approximately at the longitude of Brazzaville, an accurate orientation of the PAS system is achieved, the PAS assembly is separated from the third stage, and then, immediately, the perigee motor is ignited, burnt out and separated.

(c) The satellite is spinning on a transfer orbit about 300 km perigee and 35,000 km apogee. An accurate tracking is obtained from the Gove station (Australia) and the main data on this orbit and on the attitude of the satellite are collected.

These data are transmitted to the main Control Centre in Darmstadt. The optimum time of ignition of the apogee motor is then calculated. Ignition will take place somewhere over the Atlantic, either at the second apogee of the transfer orbit or more probably at the fourth apogee.

Two stage. Launched 24 August 1962 at 21:08. Apogee 356 miles.

BK16 was the proving trial of the Black Knight vehicle for the further re­entry physics experiments, Project Dazzle. It was a two-stage vehicle powered for the first time by a Gamma 301 engine, and a transistor control system was also tested for the first time. Ignition of the second stage was timed to occur at about 1,000,000 ft, and the head was separated from the second stage at an increased velocity in order to achieve re-entry of the head well separated (15,000 ft) from the rest of the vehicle. The head was a 15o semi-angle copper cone, shape GW20, a type to be flown later in the Dazzle programme. As with BK15, limited ground instrumentation was available to obtain some re-entry data. Dynamics and head temperature measurements during re-entry were also included in this trial.

Propulsion was very good, a re-entry velocity of 14,600 ft/second being achieved at

200,0 ft. Telemetry was successful: all engine

pressures, control system parameters and guidance data were successfully recorded

Once again, as with BK15, difficulties with guidance telescope tracking necessitated a change back to radar information for guidance until telescope tracking was

resumed.

All the aims of the trial were achieved. The Gamma 301 engine and the transistor control system were both proved in flight. Separation and ignition of the second stage and separation of the head were achieved according to plan. The FPS.16 radars

which the trajectory and all events (second stage separation, spin and ignition and head separation) were determined. The range at Woomera was provided with an excellent opportunity of rehearsing for the re-entry physics experiments to follow. The head tape recorder was recovered and data on re-entry dynamics and temperatures was obtained. The trial confirmed the expected re-entry characteristics of an uncontaminated low-drag head.

Inevitably, there were a variety of improvements suggested for Black Arrow24,25, some more realistic than others. As mentioned in the chapter on rocket motors, BSE carried out a programme to produce an improved HTP motor. The chamber that was test fired was both lighter and more efficient than the Gamma chamber used in Black Arrow, and had a higher thrust rating. This inevitably gave rise to the proposition that if the vehicle were fitted with the new chambers, then the tanks could be extended, improving performance.

The BSE report which detailed the ‘Larch’ programme suggested the following changes:

The proposal seems to have reduced the weight of the third stage: quite how is not obvious. It is easy enough to vary the amount of propellant in a liquid fuel stage, but to do so in a solid fuel stage would need some considerable redesign.

The payload increase is more than 50%, so this does seem to be a worthwhile improvement. This particular programme seems another example of the left hand not knowing what the right is doing: the RAE were making various attempts to upgrade Black Arrow yet never appear to refer to the Larch motor at all. Given that a lot of work had already been done on the chamber (but not on the full scale motors), it might seem a particularly cost-effective method of upgrading.26

The other proposal which RAE were working on at the time of cancellation was to attach four solid fuel Raven boosters to the first stage, with the empty cases being jettisoned after use. Again, the idea is similar – use the extra thrust to stretch the tanks.

Original: Proposed:

First Stage Burn time 127 seconds 200 seconds

Second Stage Burn time 117 seconds 180 seconds

In this case, both the first and the second stage tanks have been extended. The result is an increase of payload to 470 lb, which is effectively double that of the unboosted vehicle. The graph in Figure 118, showing the acceleration of the vehicle, is rather interesting.27 At 34 seconds, the acceleration falls to zero! This is presumably when the Raven boosters have burned out, and the upwards kink in the graph after that is a consequence of the empty cases being jettisoned. It showed that the RAE had stretched the vehicle as far as it can possibly go, and any further weight increase would have been a considerable embarrassment!

One final suggestion on improving Black Arrow came from Saunders Roe: a vehicle called SLAVE.

Rather mundanely, this abbreviation stood for Satellite LAunch VEhicle. It was a Saunders Roe proposal dated around 1970, produced independently of RAE, and suggested using four of the large Stentor chambers for the first stage. The first stage could then be stretched correspondingly.

The idea was similar to BSE’s proposal of some years previously, although there was no other connection between the two ideas. The second and third stages would have been unchanged.

This would have probably given the greatest payload of the three proposals outlined here, although developing the four chamber motor for the first stage would not have come cheap. It also had the advantage that there was still some ‘stretch’ left in the design.

On the other hand, none of these ideas address the basic issue: what was the point? If there were no satellites to be launched, then there was little point in ‘stretching’ a vehicle which had run out of uses. The whole Black Arrow saga shows the confusion running through British space policy, and how a rather dubious decision taken in 1964 limped on for another seven years before being cancelled. Again one is tempted to say: do the thing properly, or don’t do it at all.

This book would not have been possible without the help given by very many people.

Ed Andrews, the Central Services Manager of Westcott Venture Park.

Alan Bond of Reaction Engines.

Roy Dommett CBE, of the RAE and DERA, who was involved in much of the work detailed in this book, and whose sharp and percipient comments have thrown light on many of the ideas outlined.

Wayne Cocroft of English Heritage for his help and assistance with the Spadeadam and High Down sites.

Andy Davis for the photograph of the VC 10 as a Skybolt carrier.

Guy Finch for his encyclopaedic knowledge of aircraft, Blue Streak and the rocket interceptors.

Professor Edward James, who set me on this search following an interview when I applied for his MA course in Science Fiction at Reading University, and after reading his book Science Fiction in the Twentieth Century, where he notes that Dan Dare ‘gave a whole generation of British boys… a totally false impression that Britain was going to dominate the space race.’

James Macfarlane of Airborne Engineering Limited, Westcott Venture Park.

Doug Millard, Space Curator at the Science Museum, who with great kindness started me on my research by allowing me access to his filing cabinet. He also was the first to put the idea in my mind: why do you want to launch satellites anyway?

Kate Pyne, official historian at the AWRE, Aldermaston, for answering blundering questions with tact.

Dave Wright, who has pursued Blue Streak with dogged perseverance, and without those endless telephone conversations this book would not have been possible. Many of the ideas outlined in this book originated from him. Thanks too to his wife Lesley for her patience!

The staff at the Public Record Office in Kew, the ELDO section of the Historical Archives of the European Union at the European University Institute of Florence, the Coventry History Centre and the Science Museum at Wroughton.

Thanks also to David Cheek of GKN Aerospace, Susan Kinsella, Tom Lukeman, Sean Potter and Barrie Ricketson, for their help and suggestions. Any mistakes are entirely due to me.

Images and copyright:

Thanks to GKN Aerospace for supplying images. Also images from the Defence Evaluation Research Agency: © (British) Crown Copyright, 2000 Defence Evaluation and Research Agency, reproduced with the permission of the Controller Her (Britannic) Majesty’s Stationery Office.

The image of the ‘underground launcher’ on page 122 is by kind permission of English Heritage, and is copyright English Heritage. It was drawn by Allan Adams, and I am grateful to Wayne Cocroft for his help in obtaining the image.

The hot gases that exit from the rocket motor provide thrust. Rockets are (usually) launched vertically. The thrust must be bigger than the weight for the vehicle to start moving upwards. Usually, the ratio of thrust to weight is about 1.3, which means the initial acceleration is 0.3 times that due to gravity (the force driving the rocket upward is thrust minus weight). As fuel is burned off, the weight (and mass) decreases and the acceleration increases. The final velocity is governed by two factors: the speed of the exhaust gases (another way of expressing S. I.) and the ratio of the total weight of the rocket to the final, empty weight, as in the equation cited above. This latter figure becomes very important for satellite launchers, where the payload may be around only 1% of the initial weight. A small increase in weight can have a considerable impact on payload.

Thus if the Blue Streak motors could provide a total thrust of 300,000 lb, its maximum lift-off weight would be around 230,000 lb. If Blue Streak itself weighs 183,000 lb, then 47,000 lb is left for the upper stages and payload, only around 25%. A satellite launcher usually consists of three stages, and as each stage burns out, it is discarded. To make this staging as efficient as possible, the first stage should be around a half or two thirds of the total. Blue Streak was designed as a ballistic missile, and so was not as efficient a satellite launcher as it might have been.

The same problem applied to the early American launchers, but one way of overcoming the problem is to add strap-on solid fuel boosters to augment the thrust for the first part of the flight. These boosters might then provide extra thrust for the first 30 seconds or so of flight, whilst fuel from the main stage is being burned off and so reducing its weight.

A report from Westcott dated December 1956 considered the ‘Application of Solid Propellant Motors to Medium Range Ballistic Missiles’8. Its summary states that

The studies are based chiefly on the studies of motors with plastic propellant charges of maximum length 25 ft and maximum diameter 3 ft 6 in. These maximum dimensions are considered feasible with radial burning plastic propellant charges… and are within the pressing limits of facilities already planned and requested… For a missile carrying a 4,000lb warhead, fitted with clustered motor units, the ranges calculated for single stage and two stage propulsion are respectively up to 1,300 miles and up to 2,500 miles.

Not surprisingly, given the lack of experience with solid fuel motors of such size, the report is somewhat lacking in precise detail, but instead takes various arrangements of mo tors and makes an estimate (or guess) at the range obtainable from each one.

The individual motors shown in the sketches are also very generic: other than being 3 ft 6 inches diameter and 29 ft 2 inches long, there is very little information about them. Quite why these particular dimensions have been chosen is not obvious.

It is clear that the option of using solid fuel motors was not taken very seriously – there is no mention of them at all in policy papers, and it is quite possible that the study was undertaken so as to be seen to have covered all possibilities. It does not appear from the report that there had been wide consultation with those who were actually producing solid fuel motors – the limits imposed on the dimensions seem to have been rather arbitrary. Certainly there is no discussion of the degree of practicality of building motors as large as these or larger.

The payload used in the calculations is given as 4,000 lb –

Figure 36. Proposed solid fuel missile. given the later reduction in the

weight of the payload it might have

been worth revisiting some of these ideas. Unfortunately the idea of a liquid fuel missile had become too firmly entrenched by then – which is, in many ways, a pity. For comparison, let us look at the American solid fuel Minuteman missile.

The US Air Force began looking at the possibility of solid fuel motors in August 1957, in response to the Navy’s Polaris missile. The task was given to Colonel Edward Hall, who calculated that ‘the ICBM version of Weapon System Q [i. e., Minuteman] would be a three-stage, solid-fuel missile approximately 65 feet long, weighing approximately 65,000 pounds, and developing approximately 100,000-120,000 pounds of thrust at launch’. The missile would be stored vertically in underground silos and ‘would accelerate so quickly that it could fly
through its exhaust flames and not be significantly damaged’. The system was approved in February 1958 and the first successful launch was in February 1961, when the re-entry vehicle travelled a distance of 4,600 miles. Its design range was 5,500 miles. The first stage was 65 inches in diameter and 22 ft high; the whole missile was 55 ft tall – in other words, shorter than Blue Streak, almost half the diameter, a third of the weight, and it could deliver its payload near three times as far! The warhead yield was 1.2 MT and the re-entry vehicle plus warhead would have weighed in the or der of 1,000 lb.

Even though the US was considerably ahead in the design of solid fuel motors, developing a British solid-fuelled missile would have been quite feasible, and probably no more expensive or time consuming than developing Blue Streak, but the idea was taken no further.

The outlines of the design were now beginning to emerge: liquid fuelled, two motors, all up weight approaching 200,000 lb. It took some time for a more detailed design to emerge, however. Thus Joe Lyons of the RAE wrote in February 1956:

It had been agreed in principle that it would be a thin steel missile with propulsion at rear and the warhead at front. Titanium had been considered for the skin but was not promising. A cylindrical structure of about 10 ft diameter and length of about 60-70 ft was generally agreed. It was probable that fins would be fitted but this was not completely certain yet.9

Even the use of the NAA motors was still to be debated. A note from Serby, DG/GW (Director General/Guided Weapons at the Ministry of Supply) in March 1956 reads:

Should the missile be designed as a single-stage weapon using 2 x 135,0001b NAA motors since the AUW (All Up Weight) could be reduced and the requirement for thrust control could be eliminated if a number of smaller motors could be used?10

The thrust control issue arose from the use of large rocket motors: towards the end of the flight, when almost all the fuel was consumed, accelerations became unacceptably high. Thus there was a proposal to throttle back the motors: not an easy task.

The firms detailed to do the work had been decided back in 1955.

It is proposed that Messrs de Havilland should be responsible for the airframe and general weapon co-ordination, Rolls Royce for the rocket motor and fuel system design, Sperry for the internal inertial ‘guidance’ and autopilot, Marconi for the ground radar launching system.

Whilst relationships between the firms and the Ministry were usually good, this was not always the case with de Havilland, particularly in the early days. There were considerable cost overruns at a time of financial stringency, and at one stage the Ministry went as far as sending in Cooper Brothers, a firm of accountants from the City, to check the costs and management. And with reference to talks with Rolls Royce in 1958, the Ministry noted that

they share the view with everybody else that de Havilland can be extremely difficult and very unsatisfactory, but have no complaints to make over their immediate contacts in this particular connection. Indeed, at the working technical levels, they have a very high opinion of the de Havilland staff, but, here again, they fully share the general view about de Havilland top level people.11

To be fair, we are not given de Havilland’s views on Rolls Royce!

The debate as to the missile structure had been effectively settled by April 1957, when Wing Commander Bonser of the Ministry of Supply noted that:

A list of equipment required for the building of the ‘Blue Streak’ airframe has been submitted by the De Havilland Aircraft Division…

The equipment is required to reproduce that used by Convair for the production of the same type of pressurised structure for an American Ballistic missile. This type of structure is unique to Ballistic missiles and consists of a series of rings in stainless steel and seam welded. These rings are then welded together and fitted with stainless steel domes to form the main tanks for the liquid oxygen and kerosene. The resulting structure is of such strength that it must be kept under pressure in order to retain shape.

This very light structure and the method of production has been developed by Convairs over a very long period (5-10 years) and to save time is to be copied by De Havilland. So important is this feature of the ‘Blue Streak’ programme that it has been decided that the British missile shall have the same diameter as the American one. This means that the tools, jigs and fixtures can be reproduced with the minimum loss of time – a most important feature as the first structure is required by mid-1957.

It might be thought that work could now go ahead on Blue Streak without any further problems, but with Blue Streak that was never the case. There was constant opposition to the project throughout its life within Whitehall. This surfaces most clearly in the Treasury, but other ministries such as the Admiralty, were also against the project, as we shall see. Indeed, even the Permanent Secretary at the Ministry of Supply, the Ministry whose job it was to develop Blue Streak, was against the project. Sir Roger Makins of the Treasury, one of the ‘Great and the Good’ of the 1950s and 1960s, reported a conversation thus:

Sir Cyril Musgrave, of the Ministry of Supply, came to see me on 14th November [1956], to talk about the Medium Range Ballistic Missile. His primary objective was to talk about Spadeadam, and when I told him the Chancellor had made a decision, the main point of his visit was lost. However, he did say that the Ministry of Supply was having great difficulty in holding De Havillands at arm’s length, particularly now that the American Government had approved the contract with Convair.

I explained that the Chancellor had felt it desirable to hold up his approval of this transaction until he had an opportunity of considering the future of the M. R.B. M. in relation to the rest of the air weapons programme. On this, I believed that the Ministry of Defence were on the point of producing a paper. I would certainly do what I could to accelerate both its appearance and consideration. Sir Cyril Musgrave turned out to be a bitter opponent of the M. R.B. M. and a passionate advocate of the supersonic bomber [the Avro 730, cancelled in 1957]. He evidently relished locking horns with the Ministry of Defence on this subject.12

The transaction being referred to was the licencing by de Havilland of the technique for building the tanks – the decision had been taken to use the same construction method as the Atlas missile, with its ‘balloon’ stainless steel tanks. The passage about Musgrave is, on the face of it, extraordinary – the Ministry of Supply was simply a procurement ministry, and was not supposed to decide military policy. It demonstrates how blurred the lines can become at times.

The Chancellor certainly did hold up his approval. That conversation was in November 1956, the proposal had been made and put to the Americans; the Americans had agreed, but still the Treasury held out. The proposal reached the Chancellor himself (‘Rab’ Butler) on 4 July 1957 – eight months later. The memo began:

This is a proposal that de Havillands should buy from the American Company Convair some ‘knowhow’ for the development and production of a British intermediate range ballistic missile (Blue Streak). This knowhow will cost $700,000.

There is no doubt that if the Blue Streak project were finally agreed there would be no question of not approving this purchase. But although Ministers have taken decisions which go a long way towards the final decision to go ahead with Blue Streak, that final decision has not yet been taken.. ,13

Butler’s response was scrawled beneath in pencil:

No action. Anything could happen in this field in the next 6 weeks. America might offer us the knowhow. Russia might agree to a halt in atomic tests. Everyone might agree that we should not make more fissile material. We might decide not to make a British missile.14

This is misleading in so many ways that it is difficult to know where to begin. A halt in atomic tests would not make the slightest difference in the military need for a missile, nor would the amount of fissile material. The Americans might have given the UK the ‘know-how’ free (unlikely, and that avenue had probably been explored already), but not all the $700,000 was just for ‘know-how’ – it included specialised welding equipment for the tank sections.

In correspondence which took place last summer, the Financial Secretary agreed that work on the MRBM should go on but asked that expenditure and commitments should be kept down to the minimum essential until the United States Government had replied to an approach regarding the sharing of information on this and other defence R & D subjects. As far as I can gather the prospects of obtaining substantial US Government help in this field are not at all encouraging. Further, they are least encouraging in the spheres of atomic weapons, of which the M. R.B. M. is, of course, one. It is not necessary here to discuss the rights and wrongs of this state of affairs as between the US Government and her most important ally; but it is worth considering what courses of action are open to us:

(i) we can drop the whole MRBM project. This would mean either that we ceased to contribute actively ourselves to the strategic deterrent or that we did so only during the lifetime, now relatively restricted, of the bomber.

(ii) we can proceed as at present, buying (with the US government’s permission) what American information we can, but in the main relying on our own brains and effort (but knowing we are far behind both the Americans and the Russians in the ballistic missile field).

(iii) we can try to regain as much lost ground as possible, by pressing the Americans, by every means within our power, to let us have the information, or the weapons, or both, that we require.15

This is an extraordinary memo. First, it recognises the dilemma that would face Whitehall for the next four years: no missile, no deterrent. In practice, the Treasury would have been more than happy to abandon the deterrent – in the mid-1960s, it thought it had succeeded. (The Foreign Office and the Ministry of Defence were described by the Treasury at one stage as the ‘last two remaining retentionist [sic] departments’. It was the politicians of the Wilson Government that wanted to keep British nuclear weapons.) The other extraordinary feature is the way the Americans are regarded as some kind of fairy godmother. There were no ‘rights or wrongs’ in this case: there had been some controversy with regard to nuclear information in the 1940s, but that certainly did not apply to missiles. The word ‘sponging’ comes to mind on reading memos such as these.

Part of the uncertainty with regard to the MRBM was due to the uncertainties in British defence policy, and Suez had a part to play in this, as Sir Cyril Musgrave noted in November 1956:

I believe, however, that Suez has once more put the Policy Review into the background and it becomes necessary to decide immediately whether we should authorise de Havillands to sign the agreement or whether we should reveal by our continued refusal that the future of the project is in doubt. This means revealing the matter to the Americans.16

The outcome of the Suez debacle was a further rethink in defence policy under the new Prime Minister, Harold Macmillan, who appointed Duncan Sandys as the new Minister of Defence with increased powers. Part of Sandys’ policy rested on missiles and nuclear weapons, which should have made Blue Streak more secure – although, paradoxically, this proved not to be the case.

The licencing of the motor proved to be much more straightforward. Rocketdyne had been set up by North American Aviation (NAA) soon after the war to build rocket motors. There were links between NAA and Rolls Royce dating back to the Second World War, when NAA had developed the Mustang fighter. The Mustang had originally been powered by an Allison engine, which was replaced by the Packard V-1650 – a variant of the famous Rolls Royce Merlin engine. Lord Hives of Rolls Royce and NAA President ‘Dutch’ Kindelberger were thus old friends, and the agreement for Rolls Royce to licence the Rocketdyne S-3 rocket motor was relatively informal (Rolls Royce had difficulty locating the contract in the early 1960s when ELDO was being formed; Val Cleaver, the chief rocket engineer at Rolls Royce, said that Hives and Kindelberger had probably signed the deal ‘on the shake of a hand’). The agreement provided ‘for the exchange of Technical Information on Rocket engines over a period of 10 years on payment by Rolls Royce to NAA of a capitol sum of $500,000 and an annual payment of $100 000.’17

Rolls Royce initially copied the S3 design and then refined and anglicised it, so that the motor could be built with purely British components. The S3 was being developed for the American Thor and Jupiter missiles, having evolved from the original V2 design via the Navaho missile. This motor burned kerosene and liquid oxygen, standard for the time, but a combination that might, in retrospect, have appeared out of date by 1960, although this is still a matter of controversy. A copy of the design, designated the RZ 1, was built by Rolls Royce and tested at Westcott. From this, the anglicised design, the RZ 2, evolved.

Each flight model of Blue Streak was

numbered F1, F2, F3, and so on. The first

three launches – F1, F2 and F3 – were to be

just of Blue Streak itself, with a dummy

Figure 71. The Perigee Apogee nosecone weighted to simulate a payload. System, or PAS.

F4 and F5 had all dummy upper stages; F6/1 and F6/2 had live first and second stages; from F7 onwards all stages were live.

F1

F1 reached Australia on 18 January 1964. It was set up in the launch gantry, and was static fired (that is, the tanks filled and the engines ignited, but the vehicle remained tethered to the ground and not released) on 30 April. The weather caused delays to the launch throughout May, and after other delays, the launch date was set for Friday, 5 June.

A report prepared by HGR Robinson of RAE states:

The vehicle was successfully launched at 9.11 a. m. after an extremely smooth and efficient final count down, both as regards vehicle and range… The vehicle lifted off
and programmed downrange according to plan, its flight path and walking impact point following closely to nominal. At about 130 seconds, however, telemetry records indicated the commencement of incipient instability. This became marked at 140 seconds, developing into an uncontrolled corkscrew at 145 seconds. At 147.5 seconds the engine ceased thrusting, some six seconds before the planned time for engine cut. The termination of powered flight has been diagnosed as arising from fuel starvation caused by the manoeuvres of the vehicle during its final period of instability.3

The problem lay in what was called ‘fuel sloshing’ – that is, the vibrations of the vehicle caused the remaining fuel in the tanks to slosh from side to side. As the ‘slosh’ built up, the control system was unable to cope, and the vehicle corkscrewed then tumbled. It was not a difficult problem to solve – the control system could be adapted to cope, and in any case, the vibrations would be different when the upper stages were added. Figure 72 shows three frames from the film of the flight showing the last few seconds.

Velocity at engine cut: Height at engine cut: Impact range:

Impact time:

Apogee height:

(n. m. = nautical miles)

F2 and F3

Repeats of F1, F2 was launched on 20 October 1964 and F3 on 22 March 1965. Both flights were extremely successful, meeting all objectives.

Modification of the autopilot reduced the sloshing on F2 to a low and stable value; additional anti-sloshing baffles were installed in the liquid oxygen tank for F3.

F4

This was a simulation of the complete vehicle, but with dummy upper stages, and the first launch to have the motors uprated to the full 150,000 lb thrust. F4 was launched on 24 May 1966 with a planned first stage boost duration of about 144.3 seconds and with the cut-off was to have been by exhaustion of the liquid oxygen. The flight was terminated after 135 seconds by the Range Safety Officer when it appeared that the vehicle was straying outside the range boundaries. This was a somewhat controversial decision, particularly when it was found that the vehicle had been inside limits; the range officer had acted on false tracking data caused by large cross-polarisation of the tracking transponder signal.

F5

F5 was a repeat of F4, and was launched on 15 Nov 1966. The flight was a success.

F6/1

Launched on 4 August 1967, the first and second stages were live, with a dummy third stage and satellite. The first stage performance was as planned, but the explosive bolts of the first/second stage separation system fired prematurely and the second stage failed to ignite. This was thought to be caused by an electrical fault which caused the second stage electronic sequencer to be reset. This meant the command to open the main valves was not given and the motors did not fire even though the main tanks had been pressurised by the gas generator.4

F6/2

This was a repeat of F6/1, launched on 5 December 1967. Again, the first stage performance was as planned, but this time the first and second stages failed to separate.

F7

The RAE report on F7 was as follows:

This vehicle was launched on the 30th November, 1968 … The most important defect during the trial was the complete failure of the 3rd stage immediately after separation from the 2nd stage. Final assessment has been unable to establish the cause of the failure but it has highlighted three areas which may have been either singularly or in combination responsible for the failure. These are firstly the pressurisation pipes which were of rigid construction. These may have fractured and for F8 a flexible element is included. Secondly, unscheduled operation of the break up system due to spikes appearing in the signal from the WREBUS system in the second stage; filters are being fitted to F8. Thirdly, the failure could have been occasioned by a rupture of the tank diaphragm which separates the two propellant liquids. This diaphragm may have been weakened during the preparation phase, and it appears that this is the most likely cause of the failure.

F8

A paper in the ELDO archives has this to say about F8:

Following the F7 trial, the Secretariat tried to inculcate a greater awareness of the need for better technical discipline and control of operations during a trial. Meetings and discussions took place with Member States on the subject of inspection and defect reporting in particular. During the F8 trial, some improvement was obvious, but it is still apparent that these disciplines are not accepted as having the importance attached to them which the Secretariat would wish. The supply and control of spares was also still far from satisfactory in the upper stage areas.5

F8 was launched on 3 July 1969. Both the first and second stages functioned correctly, but after the signal was sent to separate the third stage, it appeared to explode. The RAE report suggests that the failure was identical to that of F7, and was not a mechanical malfunction but an electrical malfunction.

F9

The subsequent RAE report describes the flight thus:

On the 12 June 1970 the vehicle was launched at 10.40 am local time… The first stage functioned correctly as predicted in the flight plan, and the second stage separated and performed as predicted. The third stage separated from the second stage and its engines ignited correctly. After engine ignition occurred the third stage helium tanks lost pressure progressively which caused the third stage engines to lose thrust and also to give intermittent thrusting. These factors gave rise to uncovering of the fuel depletion sensors and a premature engine shut down before all the propellants were used up and before orbital velocity was achieved. The satellite did in fact separate correctly from the third stage when the engine cut off signal was given.

A second major fault which occurred during the flight of the vehicle was the non-jettisoning of the satellite fairings during second stage thrusting. This fault occurred due to the unscheduled separation of a plug and socket connection between the third stage and the satellite. This plug and socket was in the circuit which should have carried the command signal to ignite the fairing jettisoning device; the continuity of this plug and socket was monitored and a disconnect was registered at +78 seconds.

The failure to achieve orbit was a combination of these two faults. Post flight calculations show that an orbit would have been achieved by the satellite even with the under-performance of the third stage had the fairings been jettisoned. On the other hand had the third stage performed correctly the complete third stage and satellite with fairings attached should have acquired orbital velocity.

A later report pinpoints the cause of the plug failure:

Investigation has shown that upon assembly of the connector, air was sealed into the cylinder at 1 atmosphere by two toroidal seals on the piston. Upon reaching a less dense atmosphere during flight, the differential pressure was sufficient to operate the piston and to separate the plug and socket. The device operated correctly in F7 and F8 because the cylinder and piston were dismantled several times before final assembly for flight. This had the effect of slightly damaging the toroidal seals and allowing a slight air leakage to occur.

There was also a problem with the pressurisation of the third stages tanks, meaning that the thrust in the last part of the flight became irregular.

F10

For budgetary reasons, there was no F10.

F11

F11 was the first and only flight from Kourou in South America. It was launched on 5 November 1971.

During the first stage burn, the vehicle went out of control and broke up due to a failure of the electronic guidance mounted at the top of the third stage. As the vehicle accelerated, air resistance caused the temperature of the fairings to rise, and at the same time, an electrostatic charge built up on the fairings. Air at low pressure and a high temperature can conduct relatively easily; there was a discharge from the fairings to the main third stage body which disrupted the electronic systems, leading to a loss in control.

F12 and F13 were never launched: the Europa programme was abandoned on 27 April 1973. Blue Streak never flew again.

Eleven Blue Streaks were launched: F1 to F9 (there were two F6s, F6/1 and F6/2) and F11.

F12 is at French Guiana, or parts of it are. The stainless steel tanks (which would not corrode in the equatorial heat and rain) are being used as a chicken coop.

F13 is at the Deutsches Museum, Munich.

F14 is at the Aircraft Museum at East Lothian, outside Edinburgh.

F15 is at the Euro Space Centre, Redu, Belgium.

F16 was not finally completed (and is now on display at the Space Museum at Leicester).

F17 and F18: by the time of the final cancellation these vehicles were only parts, and not fully assembled.

In addition to these vehicles, several non-flight prototypes were built. These included D1 to D4, some of which were for trials at Hatfield, others were taken to Spadeadam for static firings. Another, designated DA, was shipped to Australia before the flight vehicles, and set up on the launch site for static testing. This was to test the Woomera site and give experience to the Australian team. DB was static fired at Spadeadam to check the engines. In addition, there was a further prototype vehicle, DG, used to prove the Blue Streak launch site at Kourou, in French Guiana.