Nuclear Era. Part 4
United Kingdom
Practical research to create nuclear weapons in the British Isles began in the 1940 year after, based on the experimentally obtained data, the approximate amount of uranium-235 necessary to create a critical mass was found. At the same time, in the Cavendish Laboratory, the first experiments were carried out with a laboratory reactor for uranium oxide with a neutron moderator based on heavy water. In 1942, equipment for membrane separation of uranium isotope gas mixtures was manufactured. In the 1943 year, in the midst of the war in Great Britain, the first pilot production of uranium metal was launched.
Considering that all British industrial enterprises and laboratories involved in nuclear research were in the German bombers' area of operation, the practical part of the work related to uranium enrichment on an industrial scale, it was decided to continue the construction of large nuclear reactors in Canada. However, after the start of the Manhattan Project, a secret agreement was concluded between Churchill and Roosevelt, according to which all work on creating an atomic bomb was concentrated in the United States. In fairness it should be said that this was a fully justified decision. At that time, the UK did not have enough uranium, financial, industrial and intellectual resources to quickly build nuclear weapons.
In August, 1945, when the world became aware of the atomic bomb, the first practical step towards its own nuclear weapons was the decision of the British Cabinet to establish an "Ad Hoc Committee 75". It was on this structure, up to 1947, that the responsibility for nuclear research was assigned.
The British leadership had high hopes that the Americans in the framework of allied relations will share nuclear secrets with the UK. But they were in for a cruel disappointment. After the death of Roosevelt, his verbal agreement with Churchill on cooperation between the two countries in this area was lost. In 1946, the United States adopted the Atomic Energy Act, which banned the transfer of nuclear technology and fissile materials to other countries. However, soon, in view of the fact that Great Britain was the closest ally of the United States, some relief measures were made in its attitude. And after the news of nuclear testing in the USSR, the Americans began to provide direct assistance in the creation of British nuclear weapons. The Mutual Defense Agreement concluded in 1958 between the United States and the United Kingdom resulted in British specialists and scientists getting the greatest possible access for foreigners to US nuclear secrets and laboratory research. At the same time, after the conclusion of this agreement, Great Britain lost a significant part of its national sovereignty in the nuclear field. Since the beginning of 60, British strategic nuclear weapons have come under tight US control.
In 1947, the British nuclear program was officially launched. By that time, British scientists already had an idea about the design and characteristics of the first American atomic bombs, and the matter was only in the practical implementation of this knowledge. The British immediately decided to focus on creating a more compact and promising plutonium bomb of the implosive type.
The program to create British nuclear weapons was greatly facilitated by the fact that Britain had unlimited access to rich uranium mines in the Belgian Congo (now the Democratic Republic of the Congo).
In 1948, the formation of the British nuclear industry began. The construction of research centers, uranium enrichment plants and nuclear reactors was carried out in Woolwich, Kapenhurst and Fort Holsted. A chemical and metallurgical plant was built at Hinton to extract and process fissile materials, and two graphite-gas nuclear reactors producing plutonium began operating on the coast of the Irish Sea, near the town of Siskale. The assembly of nuclear charges was carried out in Berkshire.
The first British plutonium charge was ready for testing in the second half of 1952. The territory of the British Isles was not suitable for testing because of the high population density and the unpredictability of the consequences of an explosion. The Canadian authorities categorically refused to conduct a nuclear explosion at home. Taking into account all these factors, it was decided to conduct a test in Australia on the islands of Monte Bello.
At the start of the 50, the British, as an island nation, more than the Soviet bombers that were to fly over all of Europe, were afraid of submarines that could secretly approach ports and naval bases and strike with nuclear torpedoes. Therefore, the first British test nuclear explosion was underwater, the British admirals wanted to assess the possible consequences of a nuclear explosion off the coast - in particular, its impact on ships and onshore facilities.
The nuclear charge was suspended under the bottom of the frigate HMS Plym (K271), anchored in the lagoon at 400 m from the island of Trimouille. Nuclear test under the symbol "Hurricane" was conducted on October 3 1952 year, the power of the explosion was about 25 kt in TNT.
As a result of the explosion, the frigate literally evaporated, splashes of molten metal, reaching the coast, set fire to vegetation there. On the seabed, at the site of the explosion, a crater was formed with a depth of 6 m and a diameter of 200 m.
Simultaneously with nuclear tests in Great Britain, the development of weapons-grade plutonium for the manufacture of nuclear bombs, which, according to the "rainbow code" adopted in Great Britain, received the designation "Blue Danube", proceeded at an accelerated pace. In terms of their internal structure, these bombs were close to the American Mk 4. Except aviation free-falling nuclear bombs, this nuclear charge was used to create nuclear bombs, their installation was planned on the path of the advancing Soviet tank armies in Europe. Later, the design of the charge was modified, and in order to save money, a plutonium core diluted with uranium was used. According to various estimates, the UK has collected from 20 to 58 nuclear warheads of this type. The cost of producing one Blue Danube bomb was about £ 1 million. Art.
The first serial British atomic bombs of length 7,8 m, had a streamlined shape and weighed about 4500 kg. The power of the Blue Danube nuclear bombs ranged from 15 to 40 CT. To determine the height of the explosion, two mutually duplicating barometric fuses were used. It was believed that the reliability and efficiency of the first British nuclear bomb leaves much to be desired due to the use of bulky lead batteries as a power source, which were installed immediately before use.
When the bomb was placed on a bomber, the stabilizer empennage developed and opened up after being dropped. Their carriers were the Valiant bombers. These jets had a maximum speed of about 900 km / h and a range with outboard tanks - 7240 km.
Later, two more types of so-called V-bombers were armed with the Blue Danube bombs: "Victor" and "Vulcan". Acting from airfields on the British Isles, these aircraft were capable of delivering nuclear strikes against targets in Eastern Europe and the European part of the USSR.
Two more nuclear tests were carried out on the Australian islands of Monte Bello, but due to the impossibility of creating a full-fledged test complex in this area, later British nuclear tests were transferred to the Emu Field and Maraling test sites in the desert part of South Australia. Although the radiation background in the Monte Bello area is still different from the natural one, the islands are now freely visited by everyone, and there is fishing in the coastal waters.
The construction of a nuclear test site in the Australian desert at 450 km north-west of Adelaide began even before the start of tests on the Monte-Bello islands. The choice of location for the landfill, in addition to the climatic conditions suitable for testing and remoteness from large settlements, was due to the railway passing nearby, and there were several runways in the area. The first two nuclear tests were conducted in an area called Emu Field. But due to significant radiation contamination and adverse conditions, they were later transferred to the landings at Maraling.
In the period from 1955 to 1963, seven more atmospheric nuclear explosions ranging from 1 to 27 CT were carried out here. In addition to nuclear explosions directly at the Maraling site, field studies were conducted with fissile materials to work out security measures and the durability of nuclear charges when exposed to fire or non-nuclear explosions.
As a result of nuclear explosions and experiments with radioactive materials, the territory of the landfill was subjected to significant radiation contamination. A significant excess of the radiation background was recorded in the cities of Adelaide and Melbourne. Before the 2000, the British government spent over $ 110 million to clean the landfill. In addition, significant amounts were received by former civilians and military personnel affected by radiation. More than 13 million dollars was paid in compensation to the Australian tribe of thrush.
In 1956, the first British NPP Calder Hall began operating in Sellafield, where, in addition to electricity, plutonium was produced in significant quantities. In 1959, another nuclear power plant was commissioned at Chepelkross with similar reactors. This made it possible to dramatically increase the production of fissile materials and create new types of nuclear bombs.
In 1961, after the test explosions in Maraling, the first British tactical nuclear bomb “Red Beard” with a power of 5-20 CT in various modifications was put into service.
While the size and composition of the plutonium-uranium nucleus of a new nuclear bomb was similar to the “Blue Danube”, it used new actuators, automation and power systems. Instead of bulky barometric sensors, a radio altimeter was used, and a contact fuse was used as a backup. Electricity was generated by paired turbo-generators, the air for which rotation came through holes in the head of the bomb after it was dropped from the aircraft. Before the reset, the automation and heating were carried out from the onboard network of the aircraft carrier.
The use of new technical solutions made it possible to reduce the weight of the bomb to a record 800 kg for those times. This made the carriers of the bomb not only V-bombers, but also Canberra bombers and carrier-based aircraft. In total, 110 Red Beard nuclear bombs were intended for the bombers, of which 48 were stored in Cyprus and the same number in Singapore. The British carrier-based aviation had 35 bombs at its disposal, as a rule, on one aircraft carrier there were 5 nuclear charges. The Red Beard bomb carriers in navy steel deck bombers "Bukkanir".
However, despite all the advantages, the small weight and dimensions of the “Red Beard” century turned out to be not long. After 10 years of service, this nuclear bomb was replaced by more advanced models. Apparently, this is due to the impossibility of a full guarantee of security in the operation of a nuclear bomb of this type. So the aircraft of deck aviation was strictly forbidden to land on the deck of an aircraft carrier with a bomb in the internal compartment. For the landing of Air Force aircraft with a bomb on board, remote air bases were allocated. There, after conducting checks and surveys by specialists, the “core” was removed from the bomb and transported separately to the main airfield.
In the summer of 1954, the UK cabinet initiated a thermonuclear weapons development program. The first test of a British hydrogen bomb as part of Operation Grapple occurred on May 15 of the year on Malden Island. It was an air bombing dropped from a Vickers Valiant bomber. The calculated power of the explosion should have been of the order of 1957 Mt, but the actual energy output did not exceed 1 kt.
31 May 1957, the test of a device called “Orange Herald” took place in Malden. It was assumed that this warhead would be equipped with British ballistic missiles. However, despite the fact that during the tests a power of about 700 CT was reached, this option was considered unacceptable. Since the bomb used about 117 kg of uranium-235, despite the fact that the annual production of uranium-235 in the UK was about 120 kg. But the test of this charge led to the emergence of a small-scale nuclear bomb, known as "Green Grass" with a capacity of 400 CT. The reduction in the power of the bomb was due to the saving of uranium; in the warhead of the bomb it contained about 75 kg. A total of five such bombs were manufactured, and the corps from the old Blue Danube bombs were used.
The last violet granite bomb with a power of 150 CT was exploded on Malden 19 June 1957. According to modern estimates, all three tests were unsuccessful and showed the futility of ways to increase the power of a nuclear explosive device chosen by British physicists. Since the main energy release was accounted for not on “thermonuclear fuel”, but on expensive uranium-235.
In the 1957-1958, nuclear tests continued on the atoll of Kiribati (Christmas Island), six atmospheric explosions took place in this area. The transfer of tests here from Malden was caused by the desire to save time and money. In April, 1958, not far from the island as part of Operation Grab-Y, the first British hydrogen bomb with a capacity of 3 Mt was blown up. This success was achieved through the use of lithium-6 deuteride obtained from the USA and American technical and scientific assistance.
The practical result of the nuclear tests was the adoption by the British long-range aviation at the start of the 60-x thermonuclear charges of the megaton class "Yellow Sun MK 2" / "Red Snow", which finally superseded the first highly imperfect nuclear bombs "Blue Danube". Total collected about 100 thermonuclear bombs in this series, they were in service until the 1973 year.
According to its characteristics, British thermonuclear bombs are close to the American 28 Mark 1,1 Mt. But unlike American free-fall bombs, British products were not equipped with braking parachutes, their braking on the trajectory was due to the flat shape of the head part.
The relatively short operation of bulky thermonuclear bombs in long-range aviation is largely due to the fact that in the second half of the 60-s most of the Soviet strategic facilities located in the zone of British bombers were covered by the C-75 air defense system, and the airspace on the flight route was controlled by continuous radar field. At the same time, the Soviet fighter aviation regiments began to massively re-equip the Su-9 and MiG-21 supersonic. In such conditions, the British subsonic bombers to break through to protected objects with an intact air defense system of the USSR was unrealistic.
In the sphere of strategic nuclear weapons, the age of ballistic missiles was advancing, and the British, in order to prolong the operation and increase the combat capability of their rapidly aging strategic bombers, decided to equip them with supersonic cruise missiles with nuclear warheads.
In 1963, the rocket of the Victor and Vulcan bombers was a rocket, which we know as “Blue Steel” (“Blue Steel”). According to various sources, from 40 to 50 cruise missiles were produced. It was a very large rocket. Her weight was - 6 800 kg, length -10,7 m, and the span of feathering - 4 m.
The missile was equipped with 200 CT warheads or 1Mt. The liquid jet engine that runs on kerosene and hydrogen peroxide, accelerated it to speed 2,5 M. But already at the time of adoption, it became clear that the “Blue Style” is obsolete. The launch range did not exceed 240 km, and the preparation and refueling of the rocket were very complicated and dangerous procedures. The missile was not saved even by the fact that shortly after the adoption of the low-altitude version of the MK 1А appeared. In 1969, all CRs of this type were written off.
The most advanced free-fall British nuclear bomb was the WE 177, formally entered service at the end of the 1966 year. However, its mass production began only in the 1973 year. The bomb was produced in three versions: “A” - 10 CT, “B” - 450 CT, “C” - 200 CT. Modification "A" is a tactical bomb, weighing 282 kg, which could also be used as a depth charge in the Navy. Modifications "B" and "C", weighing 457 kg, were used on tactical and strategic carriers. WE 177 bombs had the ability to pre-adjust the power of the explosion. In total, more than 300 bombs of all modifications were collected.
The origin of the WE 177 bomb is not clear. By the time it was developed, Great Britain had already lost its independence in the field of nuclear weapons and after the conclusion of the Mutual Defense Agreement, all work was carried out under US control. Since the second half of the 60-x all British nuclear tests were conducted at the site in Nevada. Many experts are inclined to believe that the solutions implemented in the B177 family of American thermonuclear bombs were used to create WE 61. WE 177 bombs were in the British nuclear arsenal for a long time, their service ended in the 1998 year. After that, the composition of the weapons of British aviation nuclear weapons of destruction remained.
Already in the second half of 50, it became clear to the British military and political leadership that long-range bombers would not be able to provide guaranteed nuclear strikes in the near future. In addition, the bulky V-bomber was impossible to place in solid shelters, and they were very vulnerable at home bases for Soviet medium-range missiles. The fact that 1959 of American MRMT PGM-60 "Tor" was deployed in the UK in 17 year, by and large only worsened the position of the British, provoking the USSR in case of exacerbation of the situation to preventive actions.
In the current situation, Great Britain needed a weapon capable of solving strategic tasks for a short time interval, invulnerable to air defense weapons and capable, due to high mobility, to avoid destruction as a result of a sudden nuclear strike.
Just at that time, in the USA and the USSR, the first submarines with nuclear power plants appeared, having a theoretically unlimited range of underwater travel. The nuclear submarine with ballistic missiles on board fit perfectly into the British nuclear deterrence strategy. Realizing that designing and building from scratch complex and high-tech submarine missile carriers and missiles would take too much time for them, the British turned to their overseas allies for help.
At the beginning of 60-x, after receiving the documentation on the American LaFayette-class SSBN, in the UK, work began on the design of its own boat of a similar class. In 1963, construction began on a series of four submarines of the “Resolution” type. Compared to the American boats, the project was finalized taking into account the technical solutions used previously on British submarines. Outwardly, this was manifested in the modified contours and the transfer of horizontal rudders from the cabin to the nose of the hull.
The head boat of the Resolutions series - was transferred to the fleet in October 1967 of the year. The permanent base of all British submarine strategic missile-carriers was the Clyde naval base.
At the first stage, the British SSBNs were armed with the 16 SLBM "Polaris-A3" with a launch range of up to 4600 km. The missiles carried scatter-type warheads with three warheads up to 200 kt with a KVO around 600 m. Such warheads are capable of hitting individual closely spaced targets at a distance of 60-70 km from each other. For missiles placed on SSBNs of the “Resolution” type, 144 nuclear warheads were manufactured. This amount was considered sufficient, taking into account the fact that one of the four boats was constantly at sea on combat patrols, two in the operational readiness stage for sailing, and one in repair with unloaded SLBMs. In 1980, the modernized Polaris-A3ТК missile was launched, which was equipped with two 225 CT warheads and missile defense weapons. By 1987, all Polaris-A3 went through a program to upgrade and replace solid fuels.
The last two "Resolution" class boats were decommissioned in 1996. Currently, all four British first generation SSBNs are laid up at Naval Forces Rosyth. Their disposal is scheduled for 2016, it is planned to use remotely controlled robots.
In the middle of 80, the British leadership secured a principled agreement by the United States to supply the Trident-2 (D5) SLBMs to arm new-generation boats. The main motive in the intention to get a more long-range missile was the desire to push the British SSBN patrol areas away from the Soviet coast and thus increase their combat stability.
The development and production of nuclear warheads for the Trident 2 missiles were conducted in the UK. In this regard, from 22 on April 1983 of the year to 26 in November of 1991, seven underground nuclear tests with a capacity of 20 - 150 CT were conducted at the American nuclear test site in Nevada. It is believed that the British warheads for the British Trident-2 are structurally close to the American thermonuclear W-76. But they differ from them by the possibility of stepwise adjustment of the explosion power: 1, 5-10 and 100 CT.
At the beginning of the 90-x in the British fleet to replace the SSBN type "Resolution" came the boat type "Vanguard". For these boats in the United States was purchased 58 SLBM "Trident-2". This amount is not enough to equip four new-generation boats, each of which carries 16 missiles.
For reasons of economy, the British decided to get by with fewer missiles, since one boat out of four is constantly being repaired. In addition to the reduced number of SLBMs, it was decided to dispense with a smaller number of warheads on each rocket.
As reported in the British media on every boat on combat patrols, only 48 warheads are installed on the missiles instead of the ones provided for by 96.
Currently, the Vanguard-type SSBN with the Trident-2 SLBMs are the only carriers of British strategic nuclear weapons. According to the plans of the British Ministry of Defense, the Trident-2 missiles will be in service at least until the 2024 year. In addition to strategic carriers in the UK, apparently, there are still nuclear warheads for torpedoes. According to the statement of the head of the British Foreign Ministry, William Hague, the number of nuclear warheads ready for use is 160 units, while the total number is 225 warheads. It can be noted that the UK has the most modest nuclear arsenal of the five officially recognized by the world community of nuclear powers - permanent members of the UN Security Council.
Based on:
http://nuclearweaponarchive.org/Uk/UKOrigin.html
http://www.talkurbex.com/locations/penitential-institution-military-exploration/a-view-inside-the-secret-atomic-weapons-research-establishment-awre/
http://nuclearweaponarchive.org/Uk/UKArsenalDev.html
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