Radar Personalities

The Radar News

Radar theory

RAF Radar

Radar Personalities

Sir Robert Watson-Watt

R. Hanbury Brown

Alec Reeves

Guglielmo Marconi

Oral History

Gentlemen, that reminds me......

Radar Jargon

Help Wanted!

How it's done!


Radar, Service and Cold War links

Contact the Editor

FAQ (Frequently Asked Questions)


Radar Personalities

typical maximum range on a medium-sized aircraft depended on its height: for an aircraft at 3000 m it was about 130 km and for an aircraft at 6000 m was about 200 km.

Airborne radar

Although Watson-Watt's main concern while he was in charge of the work at Orfordness and Bawdsey Manor was to oversee the development of the coastal chain of radar stations with all the attendant complications of direction-, height- and sense-finding, gap-filling, siting and calibration of stations, identification of friend from foe (IFF), filter rooms and so on, together with the essential task of persuading the RAF to adopt all these things, that was not all he did. He gave an initial push to a wide range of applications of radar not only for the RAF but also for the Army and Navy; indeed it was not long before there were mobile ground stations and radar was to be found in ships and also steering guns and searchlights.

As one example, in early 1936, when the original team moved into Bawdsey Manor, Watson-Watt appointed Wilkins to look after the coastal chain and put Dr. E. G. Bowen in charge of the formidable task of putting radar into an aeroplane; by so doing he started the first group in the world to work on airborne radar.

What Watson-Watt realised, perhaps prompted by Tizard8, was that if the German Air Force was beaten back by day they would turn to bombing at night and we should then need airborne radar. Although the information from the coastal chain of radars should have proved to be sufficiently accurate for fighters to intercept the enemy by day, using nothing more than a radio-telephone in the fighter, something more would be needed at night. To see and identify an enemy in the dark the fighter must be very close to its target, 300 m or less, and to get into that position it would need to carry its own radar.

In the next three years the airborne group, under the lively direction of Bowen, succeeded in compressing the radar equipment sufficiently to get it into a military aircraft. It was not an easy job; the existing ground radars would have filled a small house, weighed several tons and took many kilowatts of power. Bowen decided that a viable airborne radar should not exceed 200 pounds (91 kg) in weight, 8 cubic feet (023 m3) in volume and take no more than 500 watts. To reduce the aerodynamic drag of the antennas the operating wavelength could not be much greater than 1 m, making it difficult with the available valves to produce enough transmitter power.

The first radar for night-fighters operated on a wavelength of about uS m and was called AI (Air Interception); it was delivered to Fighter Command in a Blenheim Aircraft in August 1939. As AI Mark IV it was used successfully against the night raids of early 1941g. The first radar for detecting ships and submarines also worked on a wavelength of 1.5 m and was called ASV (Air to Surface Vessels) and was delivered to the RAF in a Hudson aircraft in January 1940. As ASV Mark II it was widely used by patrol and reconnaissance aircraft all over the world and made a valuable contribution to the antisubmarine operations of Coastal Command. Following the development of the cavity magnetron by H. A. Boot and J. T. Randall at Birmingham University in 1940 it became possible to generate high transmitter power at microwaves and in due course these 1.5m radars were replaced by airborne radars working on centimetre waves. The first operational use of a centimetre-wave (9 cm) radar for AI was made10 in December 1941 and for ASV in March 1943; starting in January 1943 centimetre-wave scanning radars) in the Air Ministry in London; from there he kept a close watch on the development of radar and its use by the 11 (H2S) were used to guide the Allies' bombers to their targets over Germany.

Director of Communications Development

In July 1938 Watson-Watt left Bawdsey Manor, greatly to the regret of the staff and took up the post of Director of Communications Development (DCDRAE He was replaced as Superintendent of Bawdsey Research Station by A. P. Rowe who, as has already been said, was the original secretary of the Committee for the Scientific Study of Air Defence. Sometime in 1939 Sir George Lee took over the job of DCD and Watson-Watt was appointed Scientific Advisor on Telecommunications (SAT) to the Air Ministry and later to the Ministry of Aircraft Production as well. He was knighted in 1942.

The 'invention' of radar

It is often pointed out that Watson-Watt was not the only man to invent radar. For example, Sean Sword's book3 'Technical history of the beginnings of radar' notes that the suggestion that radio waves should be used to detect distant metallic objects was made several times before 1935, notably by Christian Hulsineyer in Germany in 1904. More recently, Young and Page carried out experiments with pulsed radar in the USA at about the same time as Watson-Watt's team at Orfordness. Indeed, although Watson-Watt may not have been the first man in the world to invent radar he was the first man to apply it successfully to an urgent and important problem and at the right time. To quote

Previous page

Top of page

Next page

Updated 18/12/00

Constructed by Dick Barrett

Email: editor@ban_spam_radarpages.co.uk

(To e-mail me remove "ban_spam_" from my address)

ęCopyright 2000 Dick Barrett

The right of Dick Barrett to be identified as author of this work has been asserted by him in accordance with the Copyright, Designs and Patents Act 1988.