Watson-Watt, Sir Robert Alexander

SUBJECT AREA: Aerospace, Electronics and information technology, Weapons and armour

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b. 13 April 1892 Brechin, Angus, Scotland

d. 6 December 1973 Inverness, Scotland

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Scottish engineer and scientific adviser known for his work on radar.

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Following education at Brechin High School, Watson-Watt entered University College, Dundee (then a part of the University of St Andrews), obtaining a BSc in engineering in 1912. From 1912 until 1921 he was Assistant to the Professor of Natural Philosophy at St Andrews, but during the First World War he also held various posts in the Meteorological Office. During. this time, in 1916 he proposed the use of cathode ray oscillographs for radio-direction-finding displays. He joined the newly formed Radio Research Station at Slough when it was opened in 1924, and 3 years later, when it amalgamated with the Radio Section of the National Physical Laboratory, he became Superintendent at Slough. At this time he proposed the name "ionosphere" for the ionized layer in the upper atmosphere. With E.V. Appleton and J.F.Herd he developed the "squegger" hard-valve transformer-coupled timebase and with the latter devised a direction-finding radio-goniometer.

In 1933 he was asked to investigate possible aircraft counter-measures. He soon showed that it was impossible to make the wished-for radio "death-ray", but had the idea of using the detection of reflected radio-waves as a means of monitoring the approach of enemy aircraft. With six assistants he developed this idea and constructed an experimental system of radar (RAdio Detection And Ranging) in which arrays of aerials were used to detect the reflected signals and deduce the bearing and height. To realize a practical system, in September 1936 he was appointed Director of the Bawdsey Research Station near Felixstowe and carried out operational studies of radar. The result was that within two years the East Coast of the British Isles was equipped with a network of radar transmitters and receivers working in the 7–14 metre band—the so-called "chain-home" system—which did so much to assist the efficient deployment of RAF Fighter Command against German bombing raids on Britain in the early years of the Second World War.

In 1938 he moved to the Air Ministry as Director of Communications Development, becoming Scientific Adviser to the Air Ministry and Ministry of Aircraft Production in 1940, then Deputy Chairman of the War Cabinet Radio Board in 1943. After the war he set up Sir Robert Watson-Watt \& Partners, an industrial consultant firm. He then spent some years in relative retirement in Canada, but returned to Scotland before his death.

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Principal Honours and Distinctions

Knighted 1942. CBE 1941. FRS 1941. US Medal of Merit 1946. Royal Society Hughes Medal 1948. Franklin Institute Elliot Cresson Medal 1957. LLD St Andrews 1943. At various times: President, Royal Meteorological Society, Institute of Navigation and Institute of Professional Civil Servants; Vice-President, American Institute of Radio Engineers.

Bibliography

1923, with E.V.Appleton \& J.F.Herd, British patent no. 235,254 (for the "squegger"). 1926, with J.F.Herd, "An instantaneous direction reading radio goniometer", Journal of

the Institution of Electrical Engineers 64:611.

1933, The Cathode Ray Oscillograph in Radio Research.

1935, Through the Weather Hours (autobiography).

1936, "Polarisation errors in direction finders", Wireless Engineer 13:3. 1958, Three Steps to Victory.

1959, The Pulse of Radar.

1961, Man's Means to his End.

Further Reading

S.S.Swords, 1986, Technical History of the Beginnings of Radar, Stevenage: Peter Peregrinus.

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