Sir Robert Alexander Watson-Watt
Sir Robert Alexander Watson-Watt
1892-1973
Scottish Physicist
Historians of science regard radar, which uses radio waves to detect the positions of aircraft, and the atomic bomb as the two most important results of defense research in World War II. But whereas the names of J. Robert Oppenheimer (1904-1967), Enrico Fermi (1901-1954), and other creators of the bomb are well-known, that of Sir Robert Watson-Watt is hardly a household word. Yet Watson-Watt, who also coined the term "ionosphere," transformed the character of peacetime as well as wartime, and can justly be credited with saving many lives.
Watson-Watt was born on April 13, 1892, in Brechin, Scotland, the son of Patrick, a master carpenter, and Mary Matthew Watson Watt. Patrick had chosen to retain both his mother's and father's family names, but these were not hyphenated; Robert only began doing so after he was knighted in 1942.
After winning a scholarship to University College in Dundee, Watson-Watt studied electrical engineering, and became intrigued with wireless telegraphy. In 1912, he earned a bachelor of science degree in electrical engineering, and afterward worked briefly as an assistant professor at University College. With the beginning of World War I in 1914, he tried unsuccessfully to obtain a job with the British War Office, and instead went to work for the Meteorological Office. In this apparent setback were the seeds of his greatest triumph.
While working with the Meteorological Office, Watson-Watt suggested the use of radio wave triangulation as a means of tracking weather patterns. Others were receptive to the idea, but the necessary technology was years away. Once the war was over, Watson-Watt earned another bachelor of science degree, this time in physics, from the University of London. He then went to work at a field observing station in Ditton Park, Slough. In 1927, when Watson-Watt was appointed its director, this became the Radio Research Station, a unit whose mission was to conduct research on the atmosphere, the detection of naval signals—and the radio location of thunderstorms.
A strange request in 1935 led to the discovery of radar. An official of the British Air Ministry asked Watson-Watt if radio waves could be concentrated in such a fashion that they could destroy enemy aircraft. Watson-Watt and his assistant, A.F. Wilkins, explained the impossibility of such a Flash Gordon–style device, but they noted that by sending out radio waves, one could indeed detect the position of aircraft. On February 12, 1935, Watson-Watt explained this idea in a top-secret memo to the Air Ministry; later he would refer to this date as the birth of radar.
The Air Ministry responded with enthusiasm to the idea of radar, itself a term coined in the United States as an acronym for "radio detection and ranging." By then it was becoming increasingly clear that Germany was gearing up for war, and the Air Ministry hastily prepared radio stations throughout Britain. Historians would later credit radar with helping England survive the Nazi bombing raids in the Battle of Britain.
For his contribution to the war effort, Watson-Watt was knighted, and received a number of other honors as well. Following the war, he founded a consulting company, Sir Robert Watson-Watt and Partners. He was married three times, the last time in 1966, to Dame Katherine Jane Trefusis-Forbes, former head of the Women's Royal Air Force. After 1952, she and Watson-Watt lived primarily in Canada and the United States, where he apparently worked as a freelance consultant. She died in 1971, and Watson-Watt on December 5, 1973, in Inverness, Scotland.
JUDSON KNIGHT
Sir Robert Alexander Watson-Watt
Sir Robert Alexander Watson-Watt
Sir Robert Alexander Watson-Watt (1892-1973) was a British scientific civil servant who pioneered the development of radar.
Robert Watson-Watt, the youngest son of a carpenter, was born on April 18, 1892, at Brechin, Angus, Scotland. He studied electrical engineering and physics at University College, Dundee, and became assistant to the professor of natural philosophy there in 1912. In 1915 he was assigned to the Meteorological Office to assist in the location of thunderstorms by their radio emissions for the information of aviators. This led to fundamental research into atmospherics (the transient radio emissions from lightning discharges) at the Radio Research Station, Slough, England, under the aegis of government departments. By the 1930s much had been achieved there through inter alia, the development of the cathode-ray oscillograph and aerial systems. Atmospherics were located by direction finding at two or more receivers and associated with the movements of cold-air fronts.
In 1935 Watson-Watt was asked to consider the possibility of radio destruction of aircraft (the "death ray"), but with A. F. Wilkins he soon confirmed its impracticability. However, further calculations indicated the possibility of radio detection, and in February 1935 Watson-Watt's memorandum on the "location of aircraft by radio methods" was taken up by the Tizzard Committee for the scientific survey of air defense. Watson-Watt showed that a metal aircraft approximated to a linear oscillator and indicated that the secondary radiation induced when aircraft were illuminated from the ground with 50-meter radiation could be detected at ranges of tens of miles. He proposed transmitting short pulses both to increase peak output and to use the time delay in the return of the echo from the aircraft to determine range. Cross bearings from other stations could fix positions. Pulse techniques had been developed for echo-sounding the generally reflective ionosphere, but extensive refinement was required for its application to the detection of small targets. At an establishment on the North Sea coast Watson-Watt, with Wilkins, L. H. Bainbridge-Bell and E. G. Bowen, brought the system to reality and added direction finding from crossed horizontal halfwave aerials. By 1936 a home defense chain of radar stations had been approved; largely completed by 1938, it played a vital role in the Battle of Britain.
The development of radar was very much a team effort with Watson-Watt as captain. Throughout the war he was increasingly concerned in coordinating the expanding effort in the radar field. He visited the United States in 1941-1942 as an adviser. In 1946 he left government service to practice as a consultant. He was elected a fellow of the Royal Society in 1941 and was knighted in 1942.
Watson-Watt claimed the invention of radar, but, as with other classic science-based inventions, it evolved. There were precursors and simultaneity of discovery in several countries. Suffice it to say that no other saw the possibilities so clearly, and no government took up the implications more quickly. Perhaps more than any other in the history of invention, Watson-Watt was the right man in the right place at the right time.
For his work, Watson-Watt received the United States Medal for Merit in 1946. He lived in Tuxedo, New York, and briefly in Canada. But he died December 5, 1973, in his homeland of Scotland after a long illness.
Further Reading
Watson-Watt describes the development of radar from a personal point of view in his Three Steps to Victory (1957) and The Pulse of Radar: The Autobiography of Sir Robert Watson-Watt (1959). A biography is John Rowland, The Radar Man: The Story of Sir Robert Watson-Watt (1963). Briefer accounts appear in Egon Larsen, Men Who Changed the World: Stories of Invention and Discovery (1952), and Patrick Pringle, Great Discoveries in Modern Science (1955). □
Watson-Watt, Robert
J. A. Cannon