Bristol Bloodhound The Bristol Bloodhound is a British surface - to - air missile developed during the 1950s as the UK ' s main air defence weapon , and was in large - scale service with the Royal Air Force ( RAF ) and the forces of four other countries . The Bloodhound Mk . I entered service in December 1958 and the last Mk . II missile squadron stood down in July 1991 , although Swiss examples remained operational until 1999 . History . The Stage Plan . After the end of the Second World War , UK air defences were run down , on the assumption that it would be at least a decade before another war started . However , the Soviet atomic bomb test of 1949 forced a re - evaluation of that policy , and UK defence planners started studying the problems of building a more integrated air defence network than the patchwork of WWII expediencies . The Cherry Report called for a reorganisation of existing radars under the ROTOR project along with new control centres to better coordinate fighters and anti - aircraft guns . This was strictly a stop - gap measure however ; over a longer term there would be a requirement for deployment of new long - range radars in place of the Chain Home systems from the war , construction of command and control sites able to survive a nuclear attack , interceptor s of ever - increasing performance , and anti - aircraft missiles and guns to provide a last - ditch defence . The missile portion was the newest and least understood technology . In order to deploy quickly and gain experience with these systems , the " Stage Plan " was developed . " Stage 1 " called for missiles with a range of only 20 miles with capabilities against subsonic or low - supersonic attacking aircraft , which were assumed to be at medium or high altitudes . The Stage 1 missile would be used to protect the V bomber bases in the UK , as well as the British Army in the field . The Stage 1 missile would be later replaced with a much higher - performance and longer - range " Stage 2 " system in the 1960s , which would have capability against supersonic targets at longer ranges . Two entries were accepted for the original Stage 1 proposal , an already - started project from English Electric under the name " Red Shoes " , and Bristol ' s proposal under " Red Duster " . Bristol ' s efforts were fairly similar to EE ' s in most ways , although it was somewhat less mobile while offering somewhat better range . Ferranti would develop the radar and guidance system for both . Bristol was awarded a development contract in 1949 , referring to it as " Project 1220 " . Design . As the 1220 required long range , Bristol made the decision early on to use a ramjet for power . However , they had no experience with this engine design , and started a long series of tests to develop it . As the ramjet only operates effectively at high speeds over Mach 1 , Bristol built a series of testbed airframes to flight - test the engines . The first , JTV - 1 , resembled a flying torpedo with the ramjets fitted to the end of the cruciform rear fins . Early problems were ironed out and the JTV series was the first British ramjet powered aircraft to operate continually at supersonic speeds . Once the JTV testing started to proceed , Bristol studied a series of airframe designs . The first was a long tube with an intake at the front , and four delta - shaped fins arranged near the front of the fuselage . The intake and wings give it some resemblance to the English Electric Lightning , albeit with a long tube sticking out of the aft end . This arrangement left little internal room for fuel or guidance . A second design was similar , but used mid - mounted fins of reverse - delta shape ( flat at the front ) with small intakes at their root . The performance of these intakes was not well understood , and considered risky . The final design was essentially a small aircraft , with mid - set trapezoidal wing s and four small swept wing fins at the extreme rear . In this version two engines were mounted on the wing tips , similar to the JTV series mounting and better understood due to those flight tests . One unique feature of the new design was the control system , which used two rotating wings mounted midpoint rather than using control surfaces at the rear , which is more common . A " twist and steer " solution was preferred because the ramjets could not tolerate the incidence angle which a conventional steering method would create . The controls operated by rotating the wings in different directions in order to roll the airframe in - line with the desired turn , and then operating them both in unison to provide lift in that sense . A fast roll servo , caused by the low rotational inertia for roll , conferred an excellent homing performance in the last few seconds . The engines were mounted above and below these wings on short extensions . Directional stability was provided by four small cropped - delta fins at the extreme rear of the fuselage . A very large solid fuel booster launched the missile off its launcher and powered it to speeds where the ramjets could take over . Flight testing . In 1952 the design was accepted by the Combined United Kingdom / Australia Committee for Trials . A prototype of the new layout was built and flown in Wales as the 1 / 4 - scale XTV - 1 , powered by three 5 - inch boosters strapped together . This demonstrated that the overall length with the booster attached would be a significant problem in the field . In response , the original booster was re - designed as a series of four smaller rockets designed to " wrap around " the missile fuselage . This layout was tested on the 1 / 3 scale XTV - 2 , the full - sized but unpowered XTV - 3 that tested the new boosters , and finally the full - sized and powered XTV - 4 . The final modification , first tested on the XTV - 3 , was to replace the four rear fins with two larger ones , which allowed the four booster motors to be mounted on a common ring , ensuring they separated in different directions . This resulted in the definitive XTV - 5 . As the design matured , the engine requirements were finalized . The resulting Bristol Thor was originally designed in conjunction with Boeing , who had extensive experience with the similar engines of the BOMARC missile . Testing of the prototype production versions , known as XRD ( eXperimental Red Duster ) , moved to the Woomera range in South Australia in mid - 1953 . These proved very disappointing due to ramjet problems , which were traced to the use of a flare as an ignition source inside the engine . This was replaced with an igniter design from the National Gas Turbine Establishment and the problems were quickly sorted out . Firings against Jindivik target aircraft started in 1956 , and eventually 500 tests of all of the designs were completed before it entered service . Guidance was semi - automatic , with the targets initially identified by existing early warning radar sites and then handed off to the Bloodhound sites for local detection and attack . This was handled by the truck - mounted Type 83 " Yellow River " pulse radar system that could be fairly easily jammed and was vulnerable to ground ' clutter ' , thus degrading low - level capability . By the time Bloodhound was ready for deployment , the solid - fueled Red Shoes , now known as the English Electric Thunderbird , was proving successful and the British Army dropped their orders for the Bloodhound in favour of the Thunderbird . The Bloodhound Mk 1 entered British service in 1958 , and was selected for the RAAF in November of that year . Deployment of the Bloodhound Mk . I began in 1958 , initially to provide protection for the RAF ' s V bomber bases . Australian deployments started in January 1961 . Although the Bloodhound was successful technically , Government auditors found that Ferranti had made far larger profits than projected from the Bloodhound I contract . Sir John Lang chaired an inquiry into the matter . Ferranti Chairman , Sebastian de Ferranti , agreed to pay back £4 . 25 million to the government in 1964 . Further developments . By 1955 it appeared that the Stage 2 missiles were too far beyond the state of the art to be able to enter service before the Thunderbird and Bloodhound would already be obsolete . Meanwhile the much improved continuous wave radar systems being developed for the same project , Green Sparkler , were progressing quite nicely . In order to address the timing problems , interim Stages were added . " Stage 1½ " combined a slightly upgraded Thunderbird with Green Sparkler , while " Stage 1¾ " would replace the Bloodhound outright with a new missile design known as " Blue Envoy " with 150 - mile range . In 1957 the entire Stage concept was abandoned as part of the 1957 Defence White Paper . Bristol engineers sharing a taxi with their Ferranti counterparts hatched a new plan to adapt the Blue Envoy ramjets and radars to a lengthened Bloodhound , and submitted this for study . The proposal was accepted , producing the Bloodhound Mk . II . The Mk . II featured a more powerful Thor engine based on changes investigated in Blue Envoy , along with a stretched fuselage that increased fuel storage . These changes dramatically extended range from about 35 km to 80 km , pushing the practical engagement distance out to about 50 km ( although detected at a longer range , the missile takes time to travel to its target , during which it approaches the base ) . The Mk . II was guided by either the Ferranti Type 86 Firelight radar for mobile use , or the larger fixed - emplacement Marconi Type 87 " Scorpion " . In addition to its own illumination and tracking antennas , the Scorpion also added one of the receiver antennas out of a missile body on the same frame . This antenna was used to determine what the missile ' s own receiver was seeing , which was used for jamming detection and assessment . The new radars eliminated problems with ground reflections , allowing the missile to be fired at any visible target , no matter how close to the ground . Combined with the new engines , the Mk . II had an extended altitude performance between 150 ft and 65 , 000 ft . The use of a CW radar presented a problem for the semi - automatic guidance system . Continuous wave radars rely on the Doppler effect to detect moving targets , comparing returned signals to the reference signal being broadcast . However in the Bloodhound ' s case the missile was moving away from the reference signal as fast , or faster than , the target would be approaching it . The missile would need to know the velocity of the target as well as its own airspeed in order to know what frequency to look for , but this information was known only to the radar station on the ground , the missile did not broadcast any signals of its own . To solve this problem the radar site also broadcast an omnidirectional reference signal that was shifted to the frequency that the missile ' s receiver should be looking for , taking into account both the target and missile speed . Thus the missile only had to compare the signal from its nose - mounted receiver with the signal from the launch site , greatly simplifying the electronics . Many of the calculations of lead , frequency shifting , and pointing angles for the radars were handled by the custom - built Ferranti Argus computer . This machine would later go on to be a successful industrial control computer which was sold all over Europe for a wide variety of roles . The Mk . II started testing in 1963 and entered RAF service in 1964 . Unlike the Mk . I that had limited performance advantages compared to the Thunderbird , the Mk . II was a much more formidable weapon with capabilities against Mach 2 aircraft at high altitudes . Several new Bloodhound bases were set up for the Mk . II , and some of the Mk . I bases were updated to host the Mk . II . There was an export version planned , Bloodhound 21 , that had less sophisticated electronic countermeasures equipment . The planned Mk . III ( also known as RO 166 ) was a nuclear warhead - equipped Mk . II with a longer range ( around 75 miles ) achieved with improved ramjet engine and larger boosters . The project , one of several adaptations of existing British missiles to carry tactical nuclear devices , was cancelled in 1960 . The Mk . IV was a cancelled mobile version , based on Swedish Army field experience . Operational deployments . In 1956 , Second World War Battle of Britain ace , Wing Commander Frederick Higginson DFC DFM was recruited and placed in charge of the new Guided Missile Defence group inside Bristol Aircraft , charged with sales and service of the new systems . Higginson was awarded an OBE in 1963 for the overseas sales that Bloodhound gained , and promoted to the board of Bristol Aircraft in the same year . The initial Bloodhound Mk . I deployment consisted of eight missile sites : RAF Dunholme Lodge , RAF Watton , RAF Marham , RAF Rattlesden , RAF Woolfox Lodge , RAF Carnaby , RAF Warboys , RAF Breighton and RAF Misson with a trial site at RAF North Coates . The primary reason for these sites being chosen was the defence of the nearby V bomber stations . Australian deployments started with No . 30 Squadron RAAF at RAAF Base Williamtown in January 1961 . A detachment formed in Darwin in 1965 . By 1968 , the Bloodhound Mk . I missiles were obsolete , and both elements of the squadron had been disbanded by the end of November 1968 . Swiss deployments started in 1964 , and by 1967 six sites were operational with a total of nine firing units . These remained operational until 1999 when they were removed from service , and the Gubel site was declared a national historical property . After the RAF passed the nuclear deterrent role to the Royal Navy in 1970 , all Bloodhound systems within the UK were withdrawn and either stored or transferred to RAF Germany for airfield defence with No . 25 Squadron . The possibility of low - level sneak attack by bombers or cruise missiles led to a reappraisal of UK air defences , resulting in No . 85 Squadron forming at West Raynham on 18 December 1975 . With deployment of the Rapier missile to Germany , Bloodhounds were returned to England in 1983 and were in operation at four additional sites , Bawdsey , Barkston Heath , Wyton and Wattisham . These installations used both the ' fixed ' type 87 radar ( Marconi Scorpion ) and the ' mobile ' Type 86 radars ( Ferranti Firelight ) of their German deployments , with some being mounted on a 30 - foot tower to improve visibility and reduce ground reflections . In 1990 as the cold war wound down the remaining missiles were concentrated at West Raynham and Wattisham with plans to operate them until 1995 , but these were later removed in 1991 . In South East Asia , the Bloodhound was deployed with the RAF No . 65 Squadron based out of RAF Seletar , Singapore as part of the RAF Far East Air Force . With the withdrawal of British forces announced in 1968 , Singapore bought the entire Bloodhound assets of the No . 65 Squadron and established the Singapore Air Defence Command ' s 170 Squadron . The squadron was disbanded and the missile retired at a ceremony in 1994 . Basic description . The main missile is a long cylinder of magnesium frames and aluminium alloy skin with a prominent ogive nose cone at the front and some boat - tailing at the rear . Small aluminium - covered wooden cropped - delta wings are mounted midpoint , providing pitch and roll control by pivoting in unison or independently with additional steering provided by differential fuel feed to each of the ram jets . Two smaller rectangular fixed surfaces were mounted in - line with the main wings , almost at the rear of the missile . The boost engines are held together as a single assembly by a metal ring at the rear of the missile . Each motor has a small hook on the ring as well as similar one at the front holding it to the missile body . After firing , when the thrust of the rockets falls below the thrust of the now - lit ramjets , the boosters slide rearward until the front hook disengages from the missile body . The boosters are then free to rotate around their attachment to the metal ring , and are designed to rotate outward , away from the fuselage . In action , they fold open like the petals on a flower , greatly increasing drag and pulling the entire four - booster assembly away from the missile body . Small inlets on the roots of the stub wings holding the engines allow air into the missile body for two tasks . Two ram air turbine s driving turbopump s generate hydraulic power for the wing control system , and a fuel pump that feeds the engines . Smaller inlet tubes provide ram air to pressurize the fuel tanks . Kerosene fuel is held in two large rubber bag tanks in bays either side of the wing bay where the wings are attached . Electrical power was provided by a molten salt battery ignited at launch . Although in tests the Bloodhound had executed direct hits on target bombers flying at 50 , 000 ft , Mark II production models had proximity fused warheads designed to fire a hoop of metal rods and so destroy attacking aircraft without needing this degree of accuracy . Variants . Mk II . The acceleration of the Mk . II can be gauged from the data on an information board at the Bristol Aeroplane Company Museum at Kemble Airfield , Kemble , Gloucestershire , where a complete Bloodhound can be seen . The Mark of Bloodhound this data refers to is not given but is presumably the Mark II since the top speed of the Mk . I is Mach 2 . 2 : < br > " " By the time the missile has just cleared the launcher it is doing 400 mph . By the time the missile is 25 feet from the launcher it has reached the speed of sound ( around 720 mph ) . Three seconds after launch , as the four boost rockets fall away , it has reached Mach 2 . 5 which is roughly 1 , 800 mph " " Mk III . The planned Mk III ( also known as RO 166 ) was a nuclear warhead equipped Mark II with a longer range ( around 75 - mile ) achieved with improved Ramjet engine and bigger boosters . The project , one of several adaptations of existing British missiles to carry tactical nuclear devices , was cancelled in 1960 . There is evidence that the intention was to " poison " the warheads of nuclear weapons carried by an attacking force via the neutron flux emitted by the warhead . Mk IV . This would have been a mobile version of Bloodhound .