Blue Steel air-launched cruise missile

In November 1954, the United Kingdom Department of Supply issued a memorandum stressing that by the end of the 1950s, the capabilities of the USSR air defence system were projected to increase to such an extent that attempts by British long-range bombers to break through to their main targets in order to engage their free-falling thermonuclear bombs would be doomed to failure. To solve this problem it was proposed to develop a cruise missile with a powerful thermonuclear warhead, which could be used either to directly hit the target or to neutralize important air defense facilities with further penetration to the target and destruction of its bombs. The firing range of the new missile was to be at least 90 km.

The requirements for new weapons by the Air Force were specified in September 1954 following the release of Operational Requirement OR.1132. Among the requirements were: a maximum speed of the order of M = 3, a compact and powerful thermonuclear BC, the possibility of using the missile all three types of British long-range bombers class V (Valiant, Victor, Vulcan). In 1955, the Department of Supply announced the lead contractor for the development of a new missile - it became the Weapons Research Division of A.V. Roe & Co Ltd, better known as Avro. The competitor's variant, Vickers Armstrong, was rejected. Subcontractors were chosen: the development of the control system - Elliots (Elliot Brothers Ltd.) in conjunction with the Royal Aircraft Establishment (Farnborough) with the assistance of Kearfott (USA), the creation of the power plant - the Power Division of British engine builders Bristol Siddeley, the design of auxiliary onboard power supply, as well as the main power plant for the prototypes was engaged in the Guided Missile Division of de Havilland. The thermonuclear warhead was traditionally developed in the UK by the Aldermaston Atomic Weapons Research Establishment under Operational Requirement OR.1141 (codenamed Green Bamboo). During the course of the project, Avro envisaged further development of the concept of a new missile called Blue Steel. The choice of two parts (Blue + Steel) of the code designation of the project was made from special lists (so-called Rainbow Codes) of the Ministry of Supply at random in order to ensure secrecy, ie generally speaking, the name Blue Steel itself does not carry any particular semantic load. Modifications were designed to achieve longer maximum range (up to 1700 km) and higher maximum speed (up to M=4.5), but all these ideas were never realized, both for technical and financial reasons.

The direct development of the missile began in March 1956, after signing the contract with the lead contractor. The creation of the new weapon was accompanied by numerous problems. One of the most significant obstacles faced by the developers, was the inability to quickly assess the mass dimensional parameters of a promising thermonuclear warhead, which had an extremely detrimental effect on the assessment of possible characteristics of the missile itself - the inability to create a proper British thermonuclear warhead led to a delay in the creation of the missile for a period of 2 to 3 years. In 1957 the Green Bamboo BC was no longer considered a standard for the new SLCM - by 1958, scientists and engineers were already developing BC for the SLCM based on the Granite device. An important problem was the problem of selecting suitable structural materials to create the proper means of delivery for this BC. Difficulties were also encountered in creating its inertial navigation system - it was not possible to achieve acceptable accuracy and reliability. The developers also faced significant system problems in integrating all weapon systems into a single whole.

It is estimated by British scientists and engineers that it would not be possible to create a prototype of a suitable thermonuclear BC in-house before 1958, which could have a detrimental effect on the programme as a whole. The advent of a full-fledged serial BC would take several more years. Due to the circumstances, in November 1958 it was finally decided to cancel OR.1141 and to purchase a license for the production of thermonuclear BC W-28, originally intended for the American ALCM Hound Dog, from the United States under OR.1171. The changes made by the British in the American development were minimal and concerned primarily the use of their own design materials and safety options. This choice of BC was influenced by the assessments of specialists from AWRE, from whose researches an unambiguous conclusion was made - the prospective "national" BC will be larger and heavier than the "English" W-28, which was named Red Snow. In addition to the Blue Steel missile, the new BC was used on the free-falling thermonuclear bomb Yellow Sun Mk2. After determining the mass dimensional parameters of the BC work on the missile sharply accelerated.

The first mass scale models (designation W102) of the new ALCM were manufactured to a scale of 2/5 of the original and used since 1957 for drop tests over the area of the Cardigan Bay range in Wales. Mock-up throws were made from aboard Valiant and Vulcan bombers. The first batch of 6 large-scale models was subcontracted by Air Service Training from light alloys. Later, according to the results of the first stage of testing, it was decided to start manufacturing and launching of 2/3 scale models (designation W103), already equipped with RDTT and autopilot with Elliots prototype INS. After the flight program was completed, they self-liquidated. Then, a model (designation W103A) was developed, equipped with a parachute to save it after it was dropped from the carrier, an advanced prototype of the INS and the Havilland Double Spectre (according to some reports, due to unpreparedness of this Double Spectre, RDTT was also used first). These prototypes were made of aluminium alloys due to problems with the production of the required stainless steels. By the end of 1959 their testing was mostly completed. In the course of these tests the aerodynamic characteristics of layouts, operation of control system and LCD, integration with carriers were checked.

By this time, testing on the Cardigan Bay Range had ceased due to its limited size and capabilities. All further tests, including firing at maximum range, it was decided to move to Australia (a member country of the British Commonwealth), to the Woomera Missile Range, preliminary preparation for the new weapon testing began in 1956. Storage and preparation of missiles was held there, based on the so-called Weapons Research Establishment (Salisbury). To support the tests in 1957 at the Avro plant in Woodford was formed the 4th Joint Test Service Unit. It was a mixed unit of UK Air Force and civilian organisations including RAE and Avro, while Elliots, EMI, Handley Page, Hunting and the Weapons Research Establishment joined the project later, at different times. The first commander of the unit was Lieutenant Colonel Underwood, until he was replaced by Lieutenant Colonel Fennel in January 1964. The aircraft assigned to the group were Vulcan B.2 and Victor B.2; Vulcan B.1 was used occasionally.

Test planning in Australia and the preparation of equipment for the site were developed during three British field missions between 1956 and 1957. The objectives of the preliminary tests were to investigate problems related to aerodynamic stability, control and kinetic heating at supersonic speeds. Large-scale models would also be sufficient for these studies, according to experts. However, since Blue Steel was an airborne launch vehicle, its tests had a "complicating factor" for the launch vehicle, so all three types of "Series V" bombers - the alleged carriers of the new missile - had to take part in the tests at different times. The first group of specialists, the Valiant bomber and the W102 mock-up arrived in Australia directly for testing in July 1957. Subsequent departures were initially planned to continue one per month, but the next mock-up (series W103A) was launched only in February 1958. By this time the model received a solid fuel engine with a burning time of 25 seconds, which allowed to provide a range of about 60 km from the point of discharge above the range. The prototype had two telemetry sensors, and the Valiant bomber was equipped with cameras in the bombshell and on the wing tips to photograph the starting point. This was Australia's first "Blue Steel" flight with an engine and it ended in a very promising way: the engine and control system worked well and the missile, after completing the main flight program, dropped smoothly by parachute into the assembly area of the test equipment.

Until the end of 1958, 5 more models were launched. From 6 launches of the program in 1958 only half of them were recognized as successful. By that time, the experimental base of the range had undergone a serious upgrade, which helped to relatively successfully fulfill the program of launches in 1959 - out of 9 launched prototypes of the W103A prototype series only 2 did not perform the flight program. It was decided not to arm the new Valiant bombers, as the latter were to be converted into air tankers for refueling Victor and Vulcan bombers. Actually Blue Steel was planned as a temporary phenomenon, until the entry into service of British long-range bombers promising U.S. missile Skybolt.

In 1959, after the selection of BC brand, for tests prepared a model of a new series (designation W100), full-size, made of stainless steel and equipped with a Stentor LCD. The following year, the products of the W100A series were produced, equipped with the first samples of the standard INS. Due to the ongoing modernization of the technical base of the range and the fact that the appearance of carrier aircraft Victor and Vulcan was expected at the range, the testing program in 1960 was, in fact, frustrated - by the end of the year there were only two launches of W102 models to test new carriers and facilities of the range. A total of 60 full-scale mock-ups and serial missiles were planned to be launched before they were put into service. The launches began on February 22, 1961 and by the end of the year their number had reached 14, including both models of new series and serial missiles Blue Steel Mk1, designated W105. The total number of fully successful launches in 1961 did not exceed 5. In 1962 the situation slightly improved - out of 15 launches completely successful, according to British data, were "about half".

However, in September 1962, the missile was recognized by the Royal Air Force as "suitable for the task", after which serial copies began to arrive in service units. And in October 1962, British long-range bombers Vulcan B.2A (there was also the designation B.2 (BS)) have already begun to carry out an experimental - combat duty with new weapons on board. In February 1963, the first Vulcan bomber unit officially reached full operational capability. Given the low reliability of the new missile, we can assume that this decision was purely political, demonstrative: in late December 1962, the U.S. closed the Skybolt program, which was a shock to the British military and politicians. As a compensation, the US offered to provide Britain with large-scale scientific and technical assistance in developing its own maritime strategic nuclear forces, but these plans could be implemented at the maximum tension of all national forces not earlier than the late 1960s, which made long-range bombers with the Blue Steel ALCM the only national means of so-called "nuclear deterrence" for a relatively long period.

Taking into account the current situation in the field of national nuclear weapons, British scientists and engineers from the very beginning proposed a program of gradual deep upgrading of the Blue Steel missile, which was to gradually get more powerful BC, longer range, higher speed, etc. However, since the most significant part of the funding of the United Kingdom's Department of Defense was spent on financing the development of the nuclear missile submarine fleet and infrastructure, there are practically no funds left to finance Blue Steel modernization programs. The only modification of the original version was the Blue Steel Mk1A ALCM (Blue Steel Low Level Project, designated W105A), which was able to be launched at low altitudes - by the end of the first half of the 1960s, the British military, following the example of their U.S. counterparts, concluded that only the "withdrawal" of bombers from the stratosphere at low altitudes when overcoming the air defense system can increase the probability of "breakthrough" aircraft to potential targets. If the Mk1 ALCM modification was separated from the carrier at an altitude of 15.2 km, then the Mk1A version of the ALCM could, according to some reports, be used from an altitude of about 150 m. All Mk1 versions of the AEC were upgraded to Mk1A. Production costs of the Mk.1A version were 0.25 million FTL (all costs of adapting the "V-series" bombers to low altitudes were 2.2 million FTL). After Blue Steel's low-altitude launches at the Australian range "proved 100% effective", the Wittering bomber wing reached initial operational capability in 1964. Missile refinements were not particularly extensive - the main difference was that the two combustion chambers were now launched and worked together. A 30-meter-long halyard was used to initiate the launch of the WRD. The launch range under such conditions was reduced to 40-80 km instead of 280 km at high altitude, and at the launch point the bomber had to increase the pitch angle to give the missile enough space to reach the altitude. After launch, the altitude was in the order of 5.2-12.2 km, where the Stentor engine was turned off and the missile diveed to a target with a theoretically achievable CWO of 275 meters. As the lower launch boundary of Blue Steel increased, the range of its flight increased slightly. Work on promising modifications of the Blue Steel ALCM (Mk1D and Mk2) was phased out by early 1960 in favor of the never implemented Skybolt program.

In September 1963, Victor B.2's long-range bombers came on combat duty with new weapons. Three Vulcan bomber squadrons based in Scampton (617th, 27th and 83rd) and two Victor bomber squadrons at Wittering Air Base (100th and 139th) were added to the new ALCMs. Testing in Australia, meanwhile, went ahead - in 1963, 14 missiles were tested, 2 of them in the Blue Steel Mk1A version. According to published British data, all launches were "fully or partially successful". Further, only W105A missiles participated in flight tests, and all previously manufactured W105s were upgraded to W105A. By this time, weapons and equipment testing (without launches) involved in the so-called Blue Ranger operation and bombers of combat units - flying from the ALCM on external sling from their bases to Australia and back (sometimes through the U.S.).

In general, the testing of new weapons over the Australian range, although it sometimes presented a lot of surprises to the technical staff and required considerable effort, still did not do without tragic accidents. The only serious incident that nearly cost the life of the crew of a Victor bomber with Blue Steel on board occurred on August 17, 1962 (see memoirs of John Saxon, a direct participant in the incident).

All 5 units equipped with bombers and new ALCMs reached full operational capability only in 1964. In March of the same year the flight tests of the missile were completed - after 3 launches of W105A series products (1 of them failed) it was decided to start the finishing and acceptance tests, in which 11 more missiles were fired on different trajectories until October 1964, all "fully or partially successful". These were the last test launches of this ALCM. Then, in January 1965, the test program was shut down by the Labor government with the preservation of the site - it was envisaged that it could resume operations with this AESC until the end of 1965. According to some reports, 49 W105/W105A series missiles were launched during the tests, of which only 25, or 51 percent, were fully successful, demonstrating the low reliability of the new weapon. According to published materials, each serial missile was worth "more than 1 million pounds".

Originally it was planned to rearm six squadrons - three with Vulcan bombers and three with Victor - with a new missile, but delays in upgrading the latter to version B.2R led to the fact that on February 10, 1964 the third squadron of Handley Page bombers was reoriented primarily on intelligence tasks. In total, 21 Victor missiles were upgraded to the B.2R version. It should also be noted that the orientation of the British military on the promising American missile Skybolt has dealt a serious blow to the welfare of the Handley Page company. Based on the fact that each Vulcan could carry two U.S. missiles without the need for serious modifications and solving the problem with the small sub-body space of the carrier bomber, it was considered quite justified, without affecting the combat effectiveness of the bomber aviation command, "cut" the order for Victor bombers option B.2 from 57 to 32 pieces. The price of this decision was the projected savings of 14 million pounds in 1960-1965.

The contract for mass production of missiles from December 15, 1960 provided for the production of 75 copies, but later the order was reduced to 57 missiles in regular equipment (designation W105/W105A), which was enough to equip 48 bombers - each aircraft carried on the external sling under the fuselage of one SLCM. At least one bomber in each bomber squadron was maintained on constant ground combat duty. In addition, this number of ALCMs made it possible to guarantee the availability of a certain reserve in the so-called "operational reserve". For training purposes, the United Kingdom Air Force received 16 W103A missiles in the training package (without tanks, LRBMs and BC, but with a full SC) and a number of products designated W100A, suitable for launch, and intended, in British terminology, "for familiarization purposes.

At the same time, the value of these weapons as a means of carrying out combat duty and keeping nuclear deterrence forces on constant alert cannot but be questioned. When a Blue Steel aircraft was on ground combat duty, no hydrogen peroxide was poured into the suspended missile for security reasons. From the moment the take-off order was received, at least 1.5 hours had to pass to refuel it and perform other necessary procedures. Such precautions could only be lifted in the event of national alarm (this level of preparedness in the United Kingdom was introduced only once, during the 1962 Caribbean crisis). That is, in the event of a surprise nuclear attack, the main armament of the British Air Force Bombardment Command would be simply undetected! It is worth noting, however, that with the increased readiness of the United Kingdom's strategic nuclear forces, the number of bombers of each squadron on combat duty doubled. On high alert, bombers from the ALCM could be launched into the air 15 minutes after receiving a command. Repeated exercises were conducted for the withdrawal of combat-ready forces from a nuclear strike with ensuring the highest readiness, i.e., combat duty of crews right in the cockpits of fully prepared for take-off bombers from the ALCM on the external sling - in this case the take-off into the air was possible less than 2 minutes after receiving the command.

However, despite all the shortcomings of the new weapons, as of the mid 1960s the Blue Steel APC was the best that the British industry could offer its armed forces. Therefore, after the end of the transition period associated with the development of the missile in operating units, the Bombardment Command decided to launch Blue Steel training and combat operations by the crews of the Command. In addition to verifying the skills of flight and maintenance personnel in the maintenance and use of new weapons, these launches of mass-produced items were intended to confirm the validity of the technical solutions implemented under the plan to build up the missile systems and the complex. They were planned to be conducted near the British Isles from different launch vehicle heights and at different ranges (below maximum). For these purposes in the period 1966 - 1967 it was decided to use 4 serial missiles W105A in inert equipment - 2 each with Victor and Vulcan bombers, respectively. They were carried by bombers of different squadrons. The entire program was code-named Operation Fresno, and the first launch was made from the Victor carrier on May 27, 1966 over the Aberporth range in Wales, the next on August 26 of the same year also from the Victor launch vehicle. The remaining two missiles from among the allocated for the program were already fired from Vulcan launchers on May 31 and July 7, 1967, respectively. According to the published data, all these launches were successful - the launch vehicle systems and the ALCMs were operating in normal mode. At the same time, as far as it is known, in two of the four cases the actual SLCM exceeded the maximum design value up to 1.5 times - however, taking into account the high power of the standard thermonuclear BC it was considered an acceptable value. Operation Fresno launches were, according to published data, the last cases of Blue Steel ALCM deployments.

The ALCM Blue Steel began to be withdrawn from service in 1968, after SSBNs of the Resolution Class began to be delivered to the Royal Navy from Polaris-A3T SLBMs. By the end of December 1968, squadrons equipped with Victor bombers were no longer on combat duty with these SSBNs and were then converted to air tankers. The process of de-alerting the squadrons equipped with Vulcan bombers began in June 1969 and was completed by the end of December 1969. The Blue Steel was finally written off on 31 December 1970, when the Royal Navy took over the role of the national strategic nuclear deterrent force in its entirety and Vulcan bombers of the Royal Air Force returned to the "philosophy" of using only free-falling thermonuclear bombs in the event of a conflict on the European TVD.

Evaluating the Blue Steel ALCM, the British managed to create weapons that slightly increased the probability that bombers would break through the air defense system of a likely enemy, but the new missile became obsolete long before it was removed from service. Separately, it should be noted that in the second half of the 1950s, the level of British industry - once the strongest in the world - fell so much that the creation of individual new weapons by their own forces without the help of the United States has become impossible.

It is of some interest to try to compare Blue Steel with another famous AEC of that time - the American Hound Dog. First of all, it is noteworthy that there is a significant difference in the number of mass-produced missiles - American missiles were manufactured more than an order of magnitude (!) More. Because of the difference in design approaches (in particular, the use of TRD, which is noticeably more economical than LRBM), the U.S. missile had a longer range. Hound Dog had an undoubted advantage in terms of performance compared to Blue Steel - for example, the ability to carry a long combat duty in a state of high alert, including in the air. The U.S. missile had a much larger set of flight paths than the British missile, which allowed for better survivability in combat conditions. In addition, a couple of missiles could be loaded on board each Hound Dog carrier, not counting free-falling thermonuclear bombs and cruise missiles - traps, which provided greater flexibility of application and was advantageous compared to British reality, where the carrier could take on board only one SLCM Blue Steel. At equal BC power, the theoretically achievable CWO of a British missile was much smaller, but the launch results often made practical accuracy much worse and close to the corresponding value for a U.S. missile for some missile applications. However, at higher maximum flight altitudes, Blue Steel's speed was noticeably higher than that of the Hound Dog, which, combined with the lower EPR value of the missile, made it more difficult for the missile to be intercepted by air defense systems of the time.