The Tizard Mission, officially the British Technical and Scientific Mission, was a delegation from the United Kingdom that visited the United States during World War II to share secret research and development (R&D) work that had military applications. It received its popular name from the programme's instigator, Henry Tizard, a British scientist and chairman of the Aeronautical Research Committee, which had orchestrated the development of radar.
The mission travelled to the U.S. in September 1940 during the Battle of Britain. They conveyed a number of British technical and scientific secrets with the objective of securing U.S. assistance in sustaining the war effort and obtaining the industrial resources to exploit the military potential of these technologies, which Britain itself could not fully use, due to the immediate demands of other war-related production.
Referring to one such British secret, a device known as a resonant cavity magnetron, American historian James Phinney Baxter III later wrote, "When the members of the Tizard Mission brought one to America in 1940, they carried the most valuable cargo ever brought to our shores." [1] The mission also opened up channels of communication for jet engine and atomic bomb development, leading to the British contribution to the Manhattan Project, and catalyzed Allied technological cooperation during World War II.
The Tizard mission is seen as one of the key events that forged the wartime Anglo-American alliance. After the war, it became the foundation for future cooperation in scientific research at institutions within and across the United States, United Kingdom and Canada.
Britain made significant scientific advances in military technology, weapons and their components before World War II began in September 1939. [2] [3] [4] After the Fall of France in June 1940, which saw Germany overrun most of the countries of Western Europe, Germany's planned invasion of the United Kingdom, Operation Sea Lion, was preceded by its effort to establish air superiority in the Battle of Britain.
Henry Tizard was a British scientist and chairman of the Aeronautical Research Committee, which had orchestrated the development of radar before the war. He sought to initiate cooperation with the United States to further the research, development and production of radar and other technologies. The U.S. was neutral and, in many quarters, unwilling to become involved in the war, but had greater resources for development and production, which Britain sought to use. The information provided by the British delegation was subject to carefully vetted security procedures, and contained some of the greatest scientific advances made at that time. The technology Britain possessed included the greatly-improved cavity magnetron, [5] the design for the proximity VT fuse, details of Frank Whittle's jet engine and the Frisch–Peierls memorandum and MAUD Report describing the feasibility of an atomic bomb. Though these may be considered the most significant, many other technologies had also been developed, including designs for rockets, superchargers, gyroscopic gunsights, submarine detection devices, self-sealing fuel tanks and plastic explosives.
Congress had many proponents of neutrality for the USA and so there were further barriers to co-operation. Tizard decided the most productive approach would be simply to give away the information and use America's productive capacity. Neither Winston Churchill nor the radar pioneer, Robert Watson-Watt, were initially in agreement with these tactics for the mission. Nevertheless, Tizard first arranged for Archibald Hill, another scientific member of the committee, to go to Washington to explore the possibilities. Hill's report to Tizard was optimistic.
After Churchill's approval of the project, the team began gathering all technical secrets which had potential military uses. At the end of August, Tizard went to the U.S. by air to make preliminary arrangements. The rest of the mission would follow by ship. They were:
All the documents were gathered in a small trunk: a lockable metal deed box, used for holding important valuable documents such as property deeds. Bowen was allowed to take 'Magnetron Number 12' with him. After spending the night under Bowen's hotel bed, the case was strapped to the roof of a taxi to the station. An over-eager railway porter whisked it from Bowen at Euston Station to take it to the train to Liverpool and Bowen almost lost sight of it. Inconsistently, in Liverpool, the magnetron was given a full Army escort.
The team arrived in Halifax, Canada, on 6 September on board the CPR Liner Duchess of Richmond (later known as the RMS Empress of Canada), and went on to Washington, D.C., a few days later. The team of six assembled in Washington on 12 September 1940.
Tizard met Vannevar Bush, the chairman of the National Defense Research Committee, on 31 August 1940, and arranged a series of meetings with each division of the NDRC. When the American and British teams met, there was initially some cautious probing by each side to avoid giving away too much without getting anything back in exchange. [7] At a meeting hosted by NDRC's two-month-old "Microwave Committee" chairman Dr Alfred Loomis [8] at the Wardman Park Hotel on 19 September 1940 the British disclosed the technical details of the Chain Home early warning radar stations. The British thought the Americans did not have anything like this, but found it was virtually identical to the US Navy's longwave CXAM radar.
The Americans then described their microwave research done by Loomis and Karl Compton earlier in 1940. The British realised that Bell Telephone Laboratories and General Electric both could contribute a lot to receiver technology. The Americans had shown a Navy experimental shortwave 10-centimetre wavelength radar but had to admit that it had not enough transmitter power and they were at a dead end. Bowen and Cockcroft then revealed the cavity magnetron, with an amazing power output of about ten kilowatts at 10 centimetres. [8] This disclosure dispelled any tension left between the delegations, and the meeting then went smoothly. [9]
Britain was interested in the Norden bombsight. President Roosevelt apologised and said that it was not available to Britain unless it could be shown that the Germans had something similar. Tizard was not unduly dismayed as he thought there were other US technologies more useful to Britain than the bombsight, and he asked for the unit's external dimensions so that British bombers could be modified to take it, if it became available at some future date. [10]
GEC at Wembley made 12 prototype cavity magnetrons in August 1940, and No 12 was sent to America with Bowen, where it was shown on 19 September 1940 in Alfred Loomis’ apartment. The American NDRC Microwave Committee was stunned at the power level produced. However, the Bell Labs director was upset when it was X-rayed and had eight holes rather than the six holes shown on the GEC plans. After contacting (via the transatlantic cable) Dr Eric Megaw, GEC’s vacuum tube expert Megaw recalled that when he had asked for 12 prototypes he said make 10 with 6 holes, one with 7 and one with 8; there was no time to amend the drawings. And No 12 with 8 holes was chosen for the Tizard Mission. So Bell Labs chose to copy the sample; and while early British magnetrons had six cavities the American ones had eight cavities. [11]
Bowen stayed in America, and a few days later, at the General Electric labs in New Jersey, he showed the Americans that the magnetron worked. The Bell Telephone Company was given the job of making magnetrons, producing the first 30 in October 1940, and over a million by the end of the war. [7]
The Tizard delegation also visited Enrico Fermi at Columbia University and told Fermi of the Frisch–Peierls concept for an atomic bomb. Fermi was highly sceptical, mainly because his research was geared towards using nuclear power to produce steam, not atomic bombs. In Ottawa, the delegation also met a Canadian, George Laurence, who had secretly built his own slow neutron experiment. Laurence had anticipated Fermi's work by several months. [12]
Tizard met with both Vannevar Bush and George W. Lewis and told them about jet propulsion, but he revealed very little except the seriousness of British efforts. Bush later recalled: "The interesting parts of the subject, namely the explicit way in which the investigation was being carried out, were apparently not known to Tizard, and at least he did not give me any indication that he knew such details". [13] [14] Later, Bush realised that the development of the Whittle engine was far ahead of the NACA project. In July 1941 he wrote to General "Hap" Arnold, commander of the USAAF, "It becomes evident that the Whittle engine is a satisfactory development and that it is approaching production, although we yet do not know just how satisfactory it is. Certainly, if it is now in such state that the British plans call for large production in five months, it is extraordinarily advanced and no time should be lost on the matter". [14]
The Tizard mission was hailed as a success, especially for its impact on the subsequent development and deployment of radar as well as wider Allied technological cooperation during World War II. Although the German bombing of the UK was largely over by the time that the new radar systems were in production, technology such as aircraft radar and LORAN navigation greatly helped the Allied war effort in Europe and the Pacific. The development of the cavity magnetron, a key radar component, would enable the production of radar units small enough to be installed in night fighters, allow antisubmarine aircraft to locate surfaced U-boats and provide great navigational assistance to bombers. It is considered to be a significant factor in the eventual Allied victory in the Second World War. [7] [9] According to James Phinney Baxter III, Official Historian of the Office of Scientific Research and Development: "[T]he greatest of [British] contributions to radar was the development of the resonant cavity magnetron.... This revolutionary discovery... was the first tube capable of producing power enough to make radar feasible at wave lengths of less than 50 centimeters. When the members of the Tizard Mission brought one to America in 1940, they carried the most valuable cargo ever brought to our [i.e., U.S.] shores. It sparked the whole development of microwave radar". [15]
The Tizard mission caused the foundation of the MIT Radiation Lab in October 1940, which became one of the largest wartime projects, employing nearly 4,000 people at its peak. The mission also opened up channels of communication for the design and development of jet engines. Vannevar Bush recommended that arrangements should be made to produce the British engine in the United States by finding a suitable company. [14] This company turned out to be General Electric and the US Whittle engine would emerge as the General Electric I-A and subsequent production General Electric J31.
When they returned to the UK in November 1940, the delegation reported that the slow neutron research conducted by French exiles in Cambridge, Columbia (by Fermi) and Canada (by Laurence) was probably irrelevant to the war effort. Nonetheless, since nuclear boilers could have some post-war value, they arranged for some financial support for the Canadian fission experiments. George Laurence later became involved in the secret exchanges of nuclear information between the British and the Americans. The British recognized the atomic bomb was a serious possibility when Franz Simon reported in December 1940 to the British MAUD Committee that it was feasible to separate the isotope uranium-235. Following this, the British created a nuclear weapons project, code named Tube Alloys, and encouraged the United States to begin this type of research, which became the Manhattan Project. [12]
The Tizard Mission is seen as one of the key events in forging the wartime Anglo-American alliance. It was the foundation for cooperation in scientific research at institutions within and across the United States, the United Kingdom and Canada. Its legacy was marked on its 75th anniversary in 2015 by various groups including: the Massachusetts Institute of Technology, Imperial College London, Office of Naval Research, British Embassy in Washington, Canadian Embassy in Washington, National Air and Space Museum, and the Defense Visual Information Distribution Service. [16] [17] [18] [19] [20] [21] [22]
The cavity magnetron is a high-power vacuum tube used in early radar systems and subsequently in microwave ovens and in linear particle accelerators. A cavity magnetron generates microwaves using the interaction of a stream of electrons with a magnetic field, while moving past a series of cavity resonators, which are small, open cavities in a metal block. Electrons pass by the cavities and cause microwaves to oscillate within, similar to the functioning of a whistle producing a tone when excited by an air stream blown past its opening. The resonant frequency of the arrangement is determined by the cavities' physical dimensions. Unlike other vacuum tubes, such as a klystron or a traveling-wave tube (TWT), the magnetron cannot function as an amplifier for increasing the intensity of an applied microwave signal; the magnetron serves solely as an electronic oscillator generating a microwave signal from direct current electricity supplied to the vacuum tube.
Vannevar Bush was an American engineer, inventor and science administrator, who during World War II headed the U.S. Office of Scientific Research and Development (OSRD), through which almost all wartime military R&D was carried out, including important developments in radar and the initiation and early administration of the Manhattan Project. He emphasized the importance of scientific research to national security and economic well-being, and was chiefly responsible for the movement that led to the creation of the National Science Foundation.
Technology played a significant role in World War II. Some of the technologies used during the war were developed during the interwar years of the 1920s and 1930s, much was developed in response to needs and lessons learned during the war, while others were beginning to be developed as the war ended. Many wars have had major effects on the technologies that we use in our daily lives, but World War II had the greatest effect on the technology and devices that are used today. Technology also played a greater role in the conduct of World War II than in any other war in history, and had a critical role in its outcome.
Sir Henry Thomas Tizard was an English chemist, inventor and Rector of Imperial College, who developed the modern "octane rating" used to classify petrol, helped develop radar in World War II, and led the first serious studies of UFOs.
The history of radar started with experiments by Heinrich Hertz in the late 19th century that showed that radio waves were reflected by metallic objects. This possibility was suggested in James Clerk Maxwell's seminal work on electromagnetism. However, it was not until the early 20th century that systems able to use these principles were becoming widely available, and it was German inventor Christian Hülsmeyer who first used them to build a simple ship detection device intended to help avoid collisions in fog. True radar which provided directional and ranging information, such as the British Chain Home early warning system, was developed over the next two decades.
Edward George "Taffy" Bowen, CBE, FRS, was a Welsh physicist who made a major contribution to the development of radar. He was also an early radio astronomer, playing a key role in the establishment of radioastronomy in Australia and the United States.
Henry Albert Howard Boot was an English physicist who with Sir John Randall and James Sayers developed the cavity magnetron, which was one of the keys to the Allied victory in the Second World War.
The S-1 Executive Committee laid the groundwork for the Manhattan Project by initiating and coordinating the early research efforts in the United States, and liaising with the Tube Alloys Project in Britain.
The SCR-584 was an automatic-tracking microwave radar developed by the MIT Radiation Laboratory during World War II. It was one of the most advanced ground-based radars of its era, and became one of the primary gun laying radars used worldwide well into the 1950s. A trailer-mounted mobile version was the SCR-784.
The Allies of World War II cooperated extensively in the development and manufacture of new and existing technologies to support military operations and intelligence gathering during the Second World War. There are various ways in which the allies cooperated, including the American Lend-Lease scheme and hybrid weapons such as the Sherman Firefly as well as the British Tube Alloys nuclear weapons research project which was absorbed into the American-led Manhattan Project. Several technologies invented in Britain proved critical to the military and were widely manufactured by the Allies during the Second World War.
The Radiation Laboratory, commonly called the Rad Lab, was a microwave and radar research laboratory located at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts. It was first created in October 1940 and operated until 31 December 1945 when its functions were dispersed to industry, other departments within MIT, and in 1951, the newly formed MIT Lincoln Laboratory.
Albert Percival Rowe, CBE, often known as Jimmy Rowe or A. P. Rowe, was a radar pioneer and university vice-chancellor. A British physicist and senior research administrator, he played a major role in the development of radar before and during World War II.
William Alan Stewart Butement was a New Zealand-born British-Australian defence scientist and public servant. A native of New Zealand, he made extensive contributions to radar development in Great Britain during World War II, served as the first chief scientist for the Australian Defence Scientific Service, then ended his professional career with a research position in private business.
John Tasker Henderson was a Canadian Physicist whose career was with the National Research Council (NRC). Educated at McGill and London, Henderson joined the NRC in 1933 where he worked on the effects of the ionosphere on radio signals and the Direction Finder invented by A.G.L. McNaughton and W.A. Steel.
Radar in World War II greatly influenced many important aspects of the conflict. This revolutionary new technology of radio-based detection and tracking was used by both the Allies and Axis powers in World War II, which had evolved independently in a number of nations during the mid 1930s. At the outbreak of war in September 1939, both the United Kingdom and Germany had functioning radar systems. In the UK, it was called RDF, Range and Direction Finding, while in Germany the name Funkmeß (radio-measuring) was used, with apparatuses called Funkmessgerät . By the time of the Battle of Britain in mid-1940, the Royal Air Force (RAF) had fully integrated RDF as part of the national air defence.
The Committee for the Scientific Survey of Air Defence (CSSAD), also known as the Tizard Committee after its chairman, Henry Tizard, was a pre-World War II scientific mission to study the needs of anti-aircraft warfare in the United Kingdom. The Committee is best known for its role in shepherding the development of radar, and the building of the Chain Home radar array and its associated control centres. Winston Churchill credited the success of the Battle of Britain to this work.
Britain initiated the first research project to design an atomic bomb in 1941. Building on this work, Britain prompted the United States to recognise how important this type of research was, helped the U.S. to start the Manhattan Project in 1942, and supplied crucial expertise and materials that contributed to the project's successful completion in time to influence the end of the Second World War.
DZ203, a Boeing 247 airliner, was among the most important single aircraft used in the development of various airborne radar and blind-landing systems. It is particularly notable as the first aircraft to perform a completely automatic approach and landing, in January 1945.
The AN/CPS-1, also known as the Microwave Early Warning (MEW) radar, was a semi-mobile, S band, early-warning radar developed by the MIT Radiation Laboratory during World War II. It was one of the first projects attempted by the Lab and was intended to build equipment to transition from the British long-wave radar to the new microwave centimeter-band radar made possible by the cavity magnetron. The project was led by Luis Walter Alvarez.
The SCR-720 was a World War II aircraft interception radar designed by the Radiation Laboratory (RadLab) at MIT in the United States. It was used by US Army Air Force night fighters as well as the Royal Air Force (RAF) in a slightly modified version known as Radar, Aircraft Interception, Mark X, or AI Mk. X for short.
British science and technology was instrumental in winning the Second World War. This course looks at several different technological innovations undertaken in Britain in the context of the wartime period: the breaking of the German Enigma code at Bletchley Park (which Winston Churchill credited with having won the Battle of the Atlantic), the development of radar, the advances in wartime medicine and pharmacology (most notably, the first practical uses of penicillin), and the participation by British scientists in the Manhattan Project.