The Tizard Mission
Courtesy of Getty Images.The Tizard Mission was the beginning of the British and American collaboration over radar, setting precedents for future collaboration.
I. The Cavity Magnetron - The Key to Future Radar
“After 45 years, it is difficult to reproduce the drama of the occasion, but the performance of [Randall and Boot's] resonant magnetron was simply revolutionary. The power it produced was already greater than that obtained from conventional airborne transmitters... it would clearly lead to a complete revolution in every kind of radar, ground-based, shipboard and airborne.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
“The cavity magnetron was able to oscillate and give a useful power of about a kilowatt on ten centimeters, in other words, four inches wavelength... The frequency we had to deal with now was 300 times higher than shortwave radio.”
- Dr. Denis M. Robinson, Electrical Engineer, British Liaison in the MIT Rad Lab
The original cavity magnetron.
Courtesy of Getty Images.
In 1939, German radar was more advanced than British radar, but with the invention of the cavity magnetron, Germany fell behind in the "radar race".
Luftwaffe long rage search radar FuMG 41/42 "Mammut", the first phased array radar in the world.
Courtesy of the US National Archives and Records Administration via Wikimedia Commons.
German Wurzburg radar at the beach near Arromanches les Bain, Normandy, France, June 22, 1944.
Courtesy of World War II Database.
Picture taken during the second World War, in December 1944, of a German listening post destroyed at the Pointe du Raz semaphore in Brittany.
Courtesy of AFP via Getty Images.
“On encountering an object such as an aircraft, radio waves of any wavelength will be reflected to some extent; but the efficiency of reflection is diminished if the size of the target is small in relation to the wavelength [such as the Chain Home 12 m wavelength against a 10m wingspan fighter]... In the course of radio engineering up to the mid-1930s... much attraction had been perceived in the use of short wavelengths... But with the valve technology of the day, higher frequencies were difficult to generate at any great power level; thus, transmitters were limited [until the advent of the magnetron].”
- Colin Latham and Anne Stobbs, radar instructor, and radar operator (respectively), in their book Radar: A Wartime Miracle
Unit Number 12 brought to the United States in the Tizard Mission by E.G. Bowen
Courtesy of Getty Images.
“The cavity magnetron had made it possible to put into the nose of a two-engine night fighter a... [device] to focus a sufficiently narrow beam to find the German bombers in the night sky.”
- Dr. Denis M. Robinson, Electrical Engineer, British Liaison in the MIT Rad Lab
The new invention represented a technological development ahead of its time, capable of winning a war when paired with American receivers.
“When the members of the Tizard Mission brought one cavity magnetron to the America in 1940, the carried the most valuable cargo ever brought to our shores.”
- James Phinney Baxter III, Official Historian of the Office of Scientific Research and Development
II. The Tizard Mission
“[In early 1940,] Tizard foresaw that it would probably not be long before the United Kingdom would be cut off from the Continent... left to her own resources, she would soon be near the limit of her productive capacity, particularly in the all-important field of electronics...
“Even if the United States did not enter the war, it became essential for Britain to invoke both the technical resources and the productive capacity of the North American continent... Tizard made the bold suggestion that Britain should disclose her secrets to the USA in return for help on technical and production matters.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
American engineers from Bell Laboratories developing a directional wavelength antenna system, technique which has been largely developed during WWII under the name 'radar'. Engineers on the picture: H. Bird Fischer, Deloss K. Martin et James D. Sarros. 1939.
Courtesy of Photo12/Universal Images Group via Getty Images.
The proposition was first met with opposition, but as the war in France unfolded, it became evident the British would be in serious danger without the assistance.
“With German forces encamped along the Channel coast and with German submarines occupying bases along the Bay of Biscay, it was a good deal easier for Tizard to get his point across. Churchill had become Prime Minister and was now a strong supporter of Tizard's proposal. He spoke to Roosevelt directly about the need for a mission to the USA.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
Outside the “glass house” of financier and amateur scientist Alfred Loomis in Tuxedo Park, New York, on October 12, 1940. British and American scientists gathered there to lay plans for creating what became the MIT Radiation Laboratory. From left to right: Carroll Wilson, Frank Lewis, Edward Bowles, Edward G. “Taffy” Bowen, E. O. Lawrence, Alfred Loomis. This photograph was taken by Bowne’s fellow Tizard Mission member John Cockcroft.
Courtesy of the MIT Museum/Robert Buderi.
“In September [1940, after the beginning of the Battle of Britain, the British] sent a mission to the United States, headed by Sir Henry Tizard, the Chairman of the British Aeronautical Research Committee. They brought with them among other things, their big surprise, the 10 cm cavity magnetron.”
- T. A. Saad, Electrical Engineer, Theoretical/Microwave Division of the Rad Lab
When discussions on radar technology began, British scientists discovered that not even the Americans had the key to high frequency radar.
US and British radar missions, circa 1940.
Courtesy of Karl Taylor Compton via the MIT Museum.
“It was Dr. Bush's opinion that the British were farther advanced in the transmitters and that the American wave radar had better receivers. Dr. Bush was very definite that 'We were all immediately convinced that we needed a central laboratory'... MIT suggested itself.”
- From an Interview with Dr. Vannevar Bush, head of the National Defense Research Committee, August 20, 1944
III. The MIT Radiation Laboratory
“From its beginning on October 11, 1940, to its official termination on December 31, 1945, the MIT Radiation Laboratory performed a service whose importance has been understood and appreciated only by a few people. The work done there left a permanent imprint on science, technology, education, laboratory operations, radar and microwaves.”
- T. A. Saad, Electrical Engineer, Theoretical/Microwave Division of the Rad Lab
Building 20 on the MIT campus, home of the Rad Lab from 1943-1945.
Courtesy of MIT Museum/Lincoln Laboratories.
Corridor scene in the Rad Lab's famous Building 20 showing antenna on cart with test equipment.
Courtesy of the MIT Museum.
“The Radiation Laboratory was a new and unique concept in American science. It was a government-funded enterprise, placed at a university and staffed by the most highly qualified scientists... It was formed in close consultation with industry and remained hand-in-hand with them for the duration of the war. It could not fail to be an outstanding success and it became the model on which many other such laboratories were based.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
Henry Tizard, Alfred Loomis, and Lee DuBridge with equipment, 1949.
Courtesy of Lee Alvin DuBridge via the MIT Museum.
Group Portrait of MIT Radiation Laboratory, circa 1945.
Courtesy of Jerrold Reinach Zacharias via the MIT Museum.
“[From the Tizard mission], they also agreed on a program. There were three main jobs. Project I the most urgent, was microwave Aircraft Interception (AI), a system enabling one aircraft to detect another using microwave radar. Project II was a high accuracy gun laying radar, a ground system using microwave radar to control the aiming and firing at enemy aircraft. Project III was an aircraft navigation system to enable aircraft to locate themselves using radio.”
- T. A. Saad, Electrical Engineer, Theoretical/Microwave Division of the Rad Lab
Project I: Air Interception radar AI Mk VIIIA mounted on the nose of Bristol Beaufighter Mk VIF night fighter.
Courtesy of World War Photos.
Project II: Gun-laying radar; a SCR-584
Courtesy of the US Army.
Project III: Close up of spinning navigation radar on top of a boat, similar to that developed in the Rad Lab, 1964.
Courtesy of the MIT Museum.
“We continually had contact with the serving officers who were using our equipment and daily contact with the people who were flying the missions. The same was true later between the MIT scientists and the American army, air force, and navy officers. This is in amazing contrast to the Germans who, with rare exceptions, had very little interplay between the scientists and the military.”
- Dr. Denis M. Robinson, Electrical Engineer, British Liaison in the MIT Rad Lab
The brain trust of the Rad Lab’s pioneering SCR-584 gun-laying radar, Lee Davenport (left) and Ivan Getting, meet with an Army colonel atop a truck carrying an experimental model of the set during 1942 anti-aircraft trials. Just two years later, the radar proved instrumental in shooting down V-I buzz bombs aimed at London.
Courtesy of the MIT Museum/Robert Buderi.
The magnetron and the Rad Lab thus demonstrate how the pressure of war drove the scientific community to pursue innovation.
E.G. Bowen, left, is shown an American made copy of the cavity magnetron by Radiation Laboratory director L. A. DuBridge, center, and associate director I. A. Rabi, a Nobel Prize winner, right.
Courtesy of the MIT Museum/Radiation Laboratory Negative Collection/Lincoln Laboratories.
An ASG airborne fire-control radar is installed by a Rad Lab technician in the rear of a gun turret of a B-24.
Courtesy of MIT Museum/Lincoln Laboratories.
Technicians at work in the rooftop laboratory of Building 4 in 1941.
Courtesy of MIT Museum/Lincoln Laboratories.
Luis Alvarez, a powerfully creative thinker and future Nobel laureate who would also shed light on John F Kennedy’s assassination and the extinction of dinosaurs, spends his last day at the Rad lab in September 1943, bound for Los Alamos and atomic bomb work.
Courtesy of the Alvarez Family Collection/Robert Buderi.
“So my peroration is: Excellence is what really matters when providing a scientific engineering component for a technological war... clear thinking and excellence are paramount... Without the research and mind training and selection of these [scientists]... this centimeter wave radar in Britain would not have happened.”
- Dr. Denis M. Robinson, Electrical Engineer, British Liaison in the MIT Rad Lab
The joint collaboration between nations and industries began in the Tizard Mission and continued in the Rad Lab. Even after the Rad Lab dissolved in 1945, similar civilian laboratories were funded.
“Nobody had expected the Laboratory to become what Compton later called 'the greatest cooperative research establishment in the history of the world.'”
- T. A. Saad, Electrical Engineer, Theoretical/Microwave Division of the Rad Lab
“Up until [World War II], the government, academia, and industry were like three separate entities. Thus was the first time that they were brought together to work on a mutual problem... it was tremendously successful. They worked well together.”
- T. A. Saad, Electrical Engineer, Theoretical/Microwave Division of the Rad Lab
The central figure in the Wizard War, R. V. Jones almost single-handedly unraveled the secrets of German radar.
Courtesy of R.V. Jones/Robert Buderi.
The Investment in the Rad Lab
“The Laboratory in 1945 was just about the biggest thing in the business...It had designed almost half of all the radar used in the war, it was using up one-fourth of the Office of Scientific Research and Development's (OSRD) total funds; it was spending about $125,000 a day [$2,385,000 in 2024], or close to $4 million a month [$76,320,000 in 2024]. It had 3,500 people. It had developed over a hundred radar systems and attachments. Its designs had resulted in $1.5 billion dollars' [$33 billion in 2024] worth of production radar.”
- T. A. Saad, Electrical Engineer, Theoretical/Microwave Division of the Rad Lab
“A device...which I shall call a new weapon has been developed which has already radically altered the course of the war and is likely to alter it very radically in the future...a history of the development, adoption, production and military use of this weapon should be written...
“The outcome of this war and of future wars are likely to be affected or even determined by technological advances and it would well repay a considerable amount of effort... if a noteworthy case such as the one I am referring to could be thoroughly studied and analyzed and understood.”
- Alfred Loomis to Dr. Gerlach, Department of History, University of Wisconsin, January 5, 1943
17 months before D-Day.