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The Vickers Valiant was a British high-altitude jet bomber designed to carry nuclear weapons, and in the 1950s and 1960s was part of the Royal Air Force's "V bomber" strategic deterrent force. It was developed by Vickers-Armstrongs in response to Specification B.35/46 issued by the Air Ministry for a nuclear-armed jet-powered bomber. The Valiant was the first of the V bombers to become operational, and was followed by the Handley Page Victor and the Avro Vulcan. The Valiant is the only V bomber to have dropped live nuclear weapons in testing.

In 1956, Valiants operating from Malta flew conventional bombing missions over Egypt for Operation Musketeer during the Suez Crisis. From 1956 until early 1966 the main Valiant force was used in the nuclear deterrence role in the confrontation between NATO and the Warsaw Pact powers. Other squadrons undertook aerial refuelling, aerial reconnaissance and Electronic Warfare.

In 1962, in response to advances in Soviet Union surface-to-air missile (SAM) technology, the V-force fleet including the Valiant changed from high-level flying to flying at low-level to avoid high altitude SAM attacks. In 1964 it was found that Valiants showed fatigue and crystalline corrosion in wing rear spar attachment forgings. In late 1964 a repair programme was underway, but a change of Government led to the new Minister of Defence Denis Healey deciding that the Valiant should be retired from service, and this happened in early 1965. The Victor and Vulcan V-bombers remained in service until the 1980s.

Development

Background and origins

In November 1944, the Joint Technical Warfare Committee, along with a separate committee chaired by Sir Henry Tizard, examined the future potential of "weapons of war" and the accompanying Tizard Report published on 3 July 1945 made specific policy directions for the Royal Air Force (RAF) Bomber Command. After the Second World War, the policy of using heavy four-engined bombers for massed raids continued into the immediate postwar period; the Avro Lincoln, an updated version of the Avro Lancaster, became the RAF's standard bomber. In 1946, the Air Staff issued Operational Requirements OR229 and OR230 for the development of turbojet-powered heavy bombers capable of carrying nuclear weapons at high altitude and speed, without defensive armament, to act as a deterrent to hostile powers and, if deterrence failed, to perform a nuclear strike. While Short Brothers submitted a design, by Geoffrey T. R. Hill, that was judged too ambitious, the Air Staff accepted another submission from the company for a separate requirement, B.14/46, as "insurance" in case the advanced B.35/46 effort ran into trouble. Aviation authors Bill Gunston and Peter Gilchrist described Specification B.14/46 as "calling for little more than a traditional aircraft fitted with jet engines" Short submitted a conservative design to meet B.14/46, which became the S.A.4 Sperrin. Vickers initially produced a six-engine jet bomber design proposal to meet Specification B.35/46. As progress in the development of more powerful jet engines was made, this was re-worked to a four-engine proposal in 1948. The proposed design submitted by Vickers was relatively straightforward, being less aerodynamically advanced in comparison to competing bids made by rival firms.

Both Handley-Page and Avro had produced advanced designs for the bomber competition. These were produced as the Victor and the Vulcan respectively. The Air Staff decided to award contracts to each company as a form of insurance in case one of the designs failed. The submissions became known as the V bombers, or V-class, with the aircraft given names that started with the letter "V". Vickers' submission had initially been rejected as not being as advanced as the Victor and the Vulcan,

Although developing three different aircraft types in response to a single Operational Requirement (OR) was costly, events such as the Berlin Blockade had led to a sense of urgency in providing a deterrent to the Soviet Union from possible acts of aggression in Western Europe.

Prototypes

thumb|First prototype at the [[Farnborough Airshow, 1951]]

On 18 May 1951, the first prototype, serial number WB210 took to the air for its maiden flight, within the deadline that George Edwards had promised, only 27 months since the contract had been issued. This was several months before the competing Short Sperrin; the Sperrin had straight (not swept) wings and was not ordered. The Valiant pilot was Captain Joseph "Mutt" Summers, who had also been the original test pilot on the Supermarine Spitfire, and wanted to add another "first" to his record before he retired. His co-pilot on the first flight was Gabe "Jock" Bryce, who succeeded Summers as Vickers' chief test pilot upon his retirement shortly after. The next month, the Vickers Type 660 was given the official name of "Valiant", reusing the name given to the Vickers Type 131 general-purpose biplane of 1931. The name Valiant had been selected by a survey of Vickers employees.

On 11 January 1952, the first Valiant prototype was lost while making internal noise measurements for the V.1000 programme. Testing included engine shutdowns and re-lights, one of which caused a fire in the starboard wing; most of the crew managed to escape the aircraft safely, except for the co-pilot, who struck the tail after ejecting.

On 11 April 1952, the second prototype WB215 made its maiden flight, after modifications to the fuel system. It was fitted with more powerful RA.7 Avon engines with thrust each, rather than the originally planned Sapphires. It also featured more rounded air inlets, replacing the narrow slot-type intakes of the first prototype, to feed sufficient air to the more powerful engines. The short delay until the second prototype became available meant that loss of the prototype did not compromise the development schedule. The B.2 was intended to serve as a Pathfinder aircraft, flying at low level to mark targets for the main bomber force. To cope with increased air turbulence at low level, the B.2 had a strengthened airframe. In particular, the wing was strengthened with the removal of the cut-outs in the wing structure into which the main wheels retracted, allowing the wing torsion box structure to be uninterrupted and giving more room for internal fuel storage. Instead, the main landing gear, which had four wheels instead of the two wheels of the B.1, retracted backwards into large fairings set into the rear of the wings. The B.2 had a lengthened fuselage with a total length of , in contrast to a length of for the Valiant B.1, with the extra length giving room for more avionics.

The prototype B.2, serial number WJ954 first flew on 4 September 1953. Finished in a gloss black night operations paint scheme, it became known as the "Black Bomber". Its performance at low level was superior to that of the B.1 (or any other V-bomber), particularly at sea level, The B.2 prototype was used for tests for a few years, including the clearance of rocket-assisted take-offs, for the Valiant B.1 at hot or high airfields, using two Super-Sprite rocket motors. It also did extensive taxiing tests to investigate the cause of brake judder which caused a fatigue failure of the landing gear. It was scrapped in 1958. The timing of this order was key to establishing production quickly. Due to shortages of steel and other materials while setting up an assembly line at Brooklands, substantial portions of the production jigs for the Valiant were made from concrete. The first five Valiants produced were completed to a pre-production standard, the first being WP199. On 21 December 1953, the production aircraft conducted its first flight; this had again occurred within the schedule that Edwards had promised. Britain's "V-bomber" force, as it had been nicknamed in October 1952, formally entered operational service on that day. The Victor and Vulcan would soon follow the Valiant into service, for a total of three types of nuclear-armed strategic bombers in RAF service. In September 1957, the final Valiant was delivered. Valiants of 90 and 214 squadrons were used for air refuelling through the addition of a Hose Drum Unit (HDU) in the bomb bay, mounted on the same suspension units that were also used for bombs. This meant that for refuelling, the bomb-bay doors had to be opened so that the refuelling hose could be streamed (unlike later tankers where the HDU was flush with the under fuselage rather than inside a bomb bay). Several Valiants were also used for testing and development purposes, such as its use as a flying testbed during trials of the Blue Steel nuclear-armed standoff missile, which was later added to the arsenal of munitions the other V-bombers were equipped with.

Unlike the Vulcan and Victor, the Valiant did not see the production of a more capable mark 2 model. as an "unfunny" aircraft.

The Valiant had a shoulder-mounted wing and four Rolls-Royce Avon RA.3 turbojet engines, each providing up to of thrust, installed in pairs in fireproof bays in each wing root. The root chord thickness ratio of 12% allowed the Avon engines to be within the wing rather than on pods as in the contemporary Boeing B-47. This "buried engine" installation contributed to the aircraft's aerodynamic cleanness, and was British practice at the time. It made engine access for maintenance and repair difficult and increased the risk that an uncontained failure of one engine would cause damage to the adjacent engine; it also increased the complexity of the design of the main spar which had to be routed around the engines.

The wing of the Valiant used a "compound sweep" configuration, devised by Vickers aerodynamicist Elfyn Richards. Richards found that it was necessary to increase the sweep on the inboard section of the wing, a discovery which he later patented as "Improvements in Aeroplane Wing Formation" with an explanation that "the formation of the shockwaves be delayed to the same extent over the whole span of the wing"; the Valiant wing had 37° sweepback for the inner third of the wing, and 21° for the remainder. This was because the thickness/chord ratio could be reduced closer to the tips. A drogue parachute was not necessary even operating from runways as short as . Direct electrical drives were used to move the flaps and landing gear. The only hydraulically-operated equipment, the steering and brakes, was also powered by electric motors but driving hydraulic pumps instead of mechanical gearing.

thumb|left|The wing root and air intakes

Production aircraft were powered by four Avon 201 turbojet engines, with thrust. The engines also provided bleed air for the pressurisation, ice protection, and air conditioning systems. The aircraft's DC electrical generators were also driven by the engines. a jettisonable rocket booster engines pack was developed for the Valiant. Some Valiant engines had water injection, which increased takeoff thrust by about per engine.

The crew were in a pressurised compartment in the forward fuselage and consisted of a pilot, co-pilot, two navigators, and air signaller (later called an air electronics officer (AEO)). Manufacture of this pressurised section was subcontracted to Saunders-Roe. The pilot and co-pilot were located side by side on an upper level, the remaining three crew members sat at stations lower in the cockpit, and faced to the rear. The crew was reduced to five with the deleted requirement for defensive gun turrets and air gunners, an operational philosophy proved by the De Havilland Mosquito bomber of World War II. Safe escape using this exit was not considered likely. The Valiant had twin-wheel nosegear and tandem-wheel main gear that retracted outwards into recesses in the underside of the wing. Each of the main gears were equipped with multipad anti-skid disc brakes, and were telescopically linked so that a single drive motor could pull them up into the wing recesses. The brakes and steering gear were electrically powered, driving hydraulic pumps for actuation.

The electrical systems used 112 volt direct current generators, one on each engine, for functions requiring large amounts of electrical power. A 28 V DC system was used for other uses including actuators that controlled the higher-voltage system functions. Backup power came from 24 V and 96 V batteries. 115 V alternating current was provided for the radar and the actuators for the flight surfaces, flaps, air brakes and undercarriage. The pilot's controls for elevators, ailerons and rudder had an artificial feel system, the pressure for which was provided from a ram-air inlet. The aft fuselage used a semi-monocoque structure, being lighter than the centre fuselage; the Boulton-Paul-produced electro-hydraulic power units for the ailerons, elevators, and rudder were contained within this space. The Valiant had been designed with a 'Safe-Life' strategy; this combination of 'Safe-Life' and DTD683 came to be viewed as a severe mistake. In 1956, a publication within the Journal of the Institute of Metals condemned the material DTD683 as being unstable and capable of catastrophic failure when stressing the airframe close to its design limits. The "Safe-Life" design strategy was dismissed by a Lockheed engineer in a talk given to the Royal Aeronautical Society in 1956, because it did not guarantee safety from catastrophic failure.

The Valiant B.1 could carry a nuclear weapon or up to 21 conventional bombs in its bomb bay. It was designed for the early fission-based nuclear weapons and also the newer and larger thermonuclear hydrogen bombs. Large external fuel tanks under each wing with a capacity of , could be used to extend range; an auxiliary fuel tank could also be installed in the forward area of the bomb bay; the external wing tanks were fitted as standard on Valiants that were operated as aerial refuelling tankers.

Operational history

Nuclear deterrent

thumb|right|Side view of a [[Yellow Sun (nuclear weapon)|Yellow Sun nuclear bomb under the wing of Vickers Valiant XD818 at the RAF Cosford museum]]

The first squadron to be equipped with the Valiant was 138 Squadron, which formed at RAF Gaydon on 1 January 1955, with 232 Operational Conversion Unit forming at Gaydon on 21 February 1955 to convert crews to the new bomber. Valiants were originally assigned to the strategic nuclear bombing role, as were the Vulcan and Victor B.1s when they became operational. At its peak, the Valiant equipped ten RAF squadrons.

According to Gunston and Gilchrist, the Valiant had performed "extremely well" during the annual bombing competition hosted by American Strategic Air Command (SAC).

thumb|On 11 October 1956, Valiant B.1 WZ366 of [[No. 49 Squadron RAF|No. 49 Squadron became the first British aircraft to drop a live atomic bomb during the Buffalo R3/Kite test]]

On 11 October 1956, a Valiant B.1 (WZ366) of No. 49 Squadron piloted by Edwin Flavell was the first British aircraft to drop an atomic bomb when it performed a test drop of a down-rated Blue Danube weapon on Maralinga, South Australia. This occurred as part of the Operation Buffalo nuclear tests in that area. Windscreen blinds were fitted in advance of the test to protect the crew from the intense flash of light from the nuclear detonation. Following the landing of the aircraft after deploying the weapon, WZ366 was assessed for potential damage and for radioactive contamination.

On 15 May 1957, a Valiant B(K).1 (XD818) piloted by Kenneth Hubbard dropped the first British hydrogen bomb, the Short Granite, over the Pacific as part of Operation Grapple. No 49 Squadron was selected to perform the live weapon drop, and were equipped with specially-modified Valiants to conform with the scientific requirements of the tests and other precautionary measures to protect against heat and radiation. However, the measured yield was less than a third of the maximum expected although achieving a thermonuclear explosion.

On 8 November 1957 a British hydrogen bomb detonated with its planned yield in the Grapple X test. The Grapple series of tests continued into 1958, and in April 1958 the Grapple Y bomb exploded with ten times the yield of the original "Short Granite". Testing was finally terminated in November 1958, when the British government decided it would perform no more air-delivered nuclear tests. On the first night of the operation, six Valiants were dispatched to bomb Cairo West Air Base (which was aborted in flight due to potential risk to US personnel in the vicinity) while six more attacked Almaza Air Base and a further five bombed Kibrit Air Base and Huckstep Barracks.

Although the Egyptians did not oppose the attacks and there were no Valiant combat losses, the results of the raids were reported as disappointing. Although the Valiants dropped a total of of bombs, only three of the seven airfields attacked were seriously damaged. The Egyptian Air Force had been effectively destroyed in a wider series of multinational attacks of which the Valiant bombing missions had been a part. It was the last time RAF V-bombers flew a live combat mission until Avro Vulcans bombed Port Stanley airfield in the Falkland Islands during the Falklands War in 1982.

Tanker operations

Valiant tankers were flown by No. 214 Squadron at RAF Marham, operational in 1958, and No. 90 Squadron at Honington, operational in 1959. Aircraft assigned to the tanker role were fitted with a Hose Drum Unit (HDU or "HooDoo") in the bomb bay. The HDU was mounted on bomb-mounting points and could be removed, so that the aircraft could be reverted to the bomber role if required; this arrangement meant that the bomb bay doors had to be opened in order to transfer fuel to a receiver aircraft. A control panel at the radar navigator station in the cockpit was used to operate the HDU.

Long-range demonstration flights were made with in-flight refuelling by other Valiant tankers that had been positioned at airfields along the route. In 1960, a Valiant bomber flew non-stop from Marham in the UK to Singapore and in 1961 a Vulcan flew non-stop from the UK to Australia. The two tanker squadrons regularly made long range flights. These included non-stop flights from the UK to Nairobi, RAF Gan and Singapore. Other aircraft refuelled by Valiants at this time included Victor and Vulcan bombers, English Electric Lightning fighters, and de Havilland Sea Vixen and Supermarine Scimitar fighters of the Royal Navy.

Countermeasures and reconnaissance roles

Valiants of No. 18 Squadron RAF at RAF Finningley were modified to the "radio countermeasures" (RCM) role—now called "electronic countermeasures" (ECM). These aircraft were ultimately fitted with American APT-16A and ALT-7 jamming transmitters, Airborne Cigar and Carpet jammers, APR-4 and APR-9 "sniffing" receivers, and chaff dispensers. At least seven Valiants were configured to the RCM role.

Valiants of No. 543 Squadron at RAF Wyton were modified to serve in the photographic reconnaissance role. In one notable operation in 1965, Valiants of No. 543 Squadron photographed around of Rhodesia across an 11-week period. The number of hours flown by each Valiant in a year was an operational issue for the RAF.

thumb|left|Vickers Valiant on display

Later the RAE ran a similar series of tests that more closely resembled actual operational conditions including low level and taxiing; the corresponding report published in 1958 produced data that could be used to get a better grasp on which flight conditions produced the most damage, and enable a better projection of the future life span for the type.

In May 1957 Flight reported an "incident at Boscombe Down, when the wing rear spar cracked after a rocket-assisted takeoff at overload weight (the reason for the rocket-assistance)" This aircraft was the second prototype WB 215 and had not been modified with the production fix for the known weakness in the rear spar; the aircraft was subsequently broken up for wing fatigue testing after it had flown 489 hours.

After years of front-line service, in July 1964, a cracked spar was found in one of the three Valiants (either WZ394 – Wynne, or WZ389 – Morgan) on Operation Pontifex. This was followed on 6 August by a failure of the starboard wing rear spar at 30,000&nbsp;ft, in WP217, an OCU aircraft from Gaydon captained by Flight Lieutenant "Taffy" Foreman. The aircraft landed back at Gaydon but without flap deployment because damage to the starboard rear spar caused the flap rollers to come out of their guides so that the flap would not lower on that side. Later inspection of the aircraft also showed the fuselage skin below the starboard inner plane had buckled, popping the rivets; the engine door had cracked and the rivets had been pulled and the skin buckled on the top surface of the mainplane between the two engines. Both of these aircraft were PR variants.

Inspections of the entire fleet showed that the wing spars were suffering from fatigue at between 35% and 75% of the assessed safe fatigue life, probably due to low level turbulence. After this inspection, the aircraft were divided into three categories, Cat A aircraft continuing to fly, Cat B to fly to a repair base, and Cat C requiring repair before flying again. The tanker squadrons had the highest proportion of Cat A aircraft because their role had been mainly at high level. By the time the type was scrapped, only about 50 aircraft were still in service; the rest had been slowly accumulating at various RAF Maintenance Units designated as "Non effective Aircraft".

Initially there was no question of retiring the type, or even a majority of affected aircraft. Repairs were actively taking place at Valiant bases such as Marham using working parties from Vickers plus RAF technicians from the base. In January 1965, the Wilson government with Denis Healey as Secretary of State for Defence decided that the expense of the repairs could not be justified, given the short operational life left to the Valiant, and the fleet was permanently grounded as of 26 January 1965. The QRA alert that had been in place for SACEUR was maintained until the final grounding. When asked to make a statement regarding the Valiant's scrapping in the House of Commons, Denis Healey stated that it "was not in any way connected with low-level flying" and that the "last Government took the decision to continue operating the Valiant force for another four years after its planned fatigue life was complete".

Aviation author Barry Jones commented in his book that: "A question has to be asked. For two years before the demise of the Valiant, Handley Page at Radlett had 100 Hastings go through their shops. They were completely dismantled and rebuilt, having DTD683 components removed and replaced by new alloy sections. What was so special about the Hastings and why was the Valiant not treated similarly? Perhaps we will know one day – but I doubt it." A Flight report about the scrapping states "Fatigue affected all Valiants ... not only those that had been used for some low flying".

On 9 December 1964, the last Valiant tanker sortie in XD812 of 214 Squadron was refuelling Lightning aircraft over the North Sea and was recalled to land back at Marham before the scheduled exercise was completed. On the same day, the last Valiant bomber sortie was carried out by XD818.

Variants

Including the three prototypes, a total of 107 Valiants were built.

  • Valiant B.1: 37 pure bomber variants, including five pre-production Type 600, Type 667 and Type 674s, which were powered by Avon RA.14 engines with the same thrust each as the earlier Avon 201 and 34 Type 706 full-production aircraft, powered by Avon RA.28, 204 or 205 engines with thrust each, longer tailpipes and water-methanol injection for takeoff boost power.
  • Type 710 Valiant B(PR).1: eleven bomber/photo-reconnaissance aircraft. Edwards and his team had considered use of the Valiant for photo-reconnaissance from the start, and this particular type of aircraft could accommodate a removable "crate" in the bomb-bay, carrying up to eight narrow-view/high resolution cameras and four survey cameras.
  • No. 18 Squadron – Valiant equipped C Flight of 199 Squadron renumbered 18 Squadron at Finningley on 17 December 1958 and disbanded 31 March 1963.
  • No. 207 Squadron – Reformed at Marham on 1 April 1956, disbanding on 1 May 1965.
  • No. 232 Operational Conversion Unit RAF – Formed at Gaydon 21 February 1955 to train Valiant flight crews, with Victor training added in 1957. The Valiant equipped B flight disbanded in February 1965.

Accidents and incidents

  • 12 January 1952; the first Valiant prototype WB210 crashed near Bransgore following a midair fire.
  • 29 July 1955; Valiant B1 WP222 of No. 138 Squadron crashed on takeoff at RAF Wittering following aileron malfunction, killing all four crew.
  • 11 May 1956; Valiant B1 WP202 of the Royal Aircraft Establishment lost control and crashed attempting to land at Southwick Recreation Ground, near Hove in Sussex.
  • 11 July 1961: Valiant B1 WP205 of the Aircraft and Armament Experimental Establishment overshot runway and hit control caravan at Boscombe Down.
  • 3 November 1961: Valiant B(PR)K1 WZ399 of No. 543 Squadron abandoned takeoff at Offutt AFB, Nebraska, United States, caught fire after overshooting runway onto a railway line.
  • 6 May 1964: Valiant B1 WZ363 of No. 148 Squadron (although a 148 Sqn aircraft, it was on loan to, and crewed by, members of 207 Sqn) dived into the ground at night at Market Rasen, Lincolnshire.
  • 23 May 1964: Valiant B(PR)K1 WZ396 of No. 543 Squadron landed on foam with landing gear problems at RAF Manston, not repaired.
  • Cockpit sections surviving comprise XD816 at Brooklands Museum in Surrey and XD875 at Morayvia, Kinloss. A third surviving section is the cockpit of XD826 which is part of the Imperial War Museum Duxford in Cambridgeshire and the flight deck of XD857 is displayed at the Norfolk and Suffolk Aviation Museum at Flixton, Suffolk.

Specifications (Valiant B.1)

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See also

References

Notes

Citations

Bibliography

  • RAF Museum
  • Valiant History