version of the Identification Friend or Foe (IFF) system.
In consequence, in March 1935, Tizard’s committee recommended that the Treasury authorise £10,000 for large-scale experiments to be carried out under Watson-Watt’s leadership. By January 1936, these had demonstrated that it was possible to detect a plane 40 km away. New premises were acquired at Bawdsey Manor near Felixstowe, Essex, which had extensive grounds, to further investigate and develop the Radio Direction Finding (RDF) technology, which was later named radar (RAdio Detection And Ranging). Following further successful investigations, the Treasury authorised £10 million for 20 stations to be built around the coast from the Firth of Tay to the Solent, each comprising a number of steel transmitting towers and lower wooden receiving towers.
Coastal radar station, Sussex, 1940. Left: 110 metre steel transmitting towers. Right: 72 metre wooden receiving towers. Science at War (HMSO)
Radar transmitting and receiving station at coastal radar station. Science at War (HMSO)
In the development of radar the scientists worked closely with Air Marshal Sir Hugh Dowding, the Air Member for Supply and Research in 1930–36 and later Fighter Command’s commander in chief. While Harry Wimperis, an aeronautical engineer who was the Director of the Air Ministry’s Department of Scientific Research, fought inter-service battles, Watson-Watt recruited and led the research team; foresaw both the possibilities and the problems; and fought the team’s administrative battles. Among key team members were Jimmy Rowe, A. F. Wilkins, and Dr E. G. ‘Taffy’ Bowen (later instrumental in developing airborne radar), while committee members who gave influential support included the Nobel Prize winner Professor Archibald Hill and Professor Patrick Blackett. Co-operation between scientists and serving officers was exemplary; Tizard described it as ‘the great lesson of the last war’.
By the summer of 1939 the coastal radar chain comprising separate high- and low-level systems (known as Chain Home and Chain Home Low respectively) was operational, with 21 and 30 stations respectively. The fall of France not having been anticipated, the original chains had to be hastily reconfigured and augmented in the summer of 1940 to provide cover west of the Solent and for ports and cities in Wales and the North West.
The Observer (later Royal Observer) Corps, which had been established pre-war, supplemented the information derived from the radar network by reporting numbers, direction, height, and composition of enemy formations.
Despite the high visibility of the radar towers, the Germans amazingly did not make them prime targets, nor were they mentioned in a July 1940 report by the Luftwaffe’s Chief of Intelligence on the British defence system.
Rowe, Albert (‘Jimmy’) CBE (1898–1976)
A government scientist, Rowe was secretary of Tizard’s committee that oversaw the research that led to the establishment of radar. He succeeded Watson-Watt as superintendent of the Folkestone Telecommunications Research Establishment and gave priority to the erection of the coastal radar station chain. Following the Battle of Britain he directed research which led to the development of airborne radar and centimetric radar with the cavity magnetron. Despite some opposition from Bomber Command, who felt that the projects would not produce large-scale results, Rowe also led in the development of the Oboe navigation system and of H2S radar. In 1946 he moved to Australia as chief scientific officer for the British Rocket Programme. The following year he joined the Australian Department of Defence before serving as vice-chancellor of the University of Adelaide in 1948–58. He is credited with coining the phrase ‘Operational Research’ in 1935. He suffered from poor health and died in 1976.
Watson-Watt, Sir Robert KCB FRS FRAeS (1892–1973)
A government scientist who joined the Royal Aircraft Factory at Farnborough in 1914, he first worked on radio systems for detecting thunderstorms. By 1933 he was superintendent of the Radio Research Station at Slough and then, from 1936 of the RAF’s Radio Direction Finding research station near Folkestone. Having concluded that a ‘death ray’ of intense radio beams could not bring down a plane, he and his team realised that radio waves were reflected from aircraft and could be detected. Thereafter he designed the radar network that was installed and fully operational by the start of the war (and for which he was awarded £52,000). During the war he became the Air Ministry’s scientific advisor on telecommunications. Post-war he led British delegations to international conferences, established a consultancy, and lived for a while in Canada. He served as president of the Royal Meteorological Society, the Institute of Navigation, and the Institute of Professional Civil Servants, and as vice-president of the Institute of Radio Engineers in New York. Reputedly, in retirement he was caught for speeding by a radar speed-trap!
Radar variants developed by Allied scientists and engineers. Science at War (HMSO)
Other radar systems which later evolved from the Bawdsey team’s pioneering work included Airborne Interception (AI) radar (for night fighters); Air-to-Surface Vessel (ASV) radar (to aid attacks on ships); Oboe system (for improved bombing accuracy); Gee system (also for improved bombing accuracy as well as assisting bombers return to their bases); H2S (target finding for bombers); and Rebecca and Eureka used by invading paratroops. The Telecommunications Research Establishment and the Admiralty Signals Establishment were both in the forefront of such developments.
The Royal Commission on Awards to Inventors gave a tax-free sum of £87,950 to the Bawdsey team, Watson-Watt’s share being £50,000 (award No. 171). The transition from the flickering and truant radio echoes of 1936 into the reliable defence system of 1940 was ‘one of the greatest combined feats of science, engineering and organization in the annals of human achievement’.
Dowding Joins up the Dots
Following the development of radar, Air Chief Marshall Hugh ‘Stuffy’ Dowding designed an integrated air defence system of Ground-Controlled Interception (GCI). Known as the Dowding system, it constituted: a number of radar stations; the Observer Corps’, human observers; raid plotters at Fighter Command’s headquarters at Bentley Priory (a converted country house near Stanmore, north London), and at various Group headquarters; and control of aircraft by radio. The land-based components were integrated by dedicated phone and teleprinter links buried sufficiently deep enough to provide protection against bombing.
In the operations room at Bentley Priory sat Dowding and Air Vice Marshal Keith (later Sir Keith) Park, a New Zealander who was the commander of No. 11 Group and as such responsible for Fighter Command’s operations in southern England. Also there were Lieutenant-General Sir Frederick Pile, commander of the Army’s Anti-Aircraft Command; the commandant of the Observer Corps; and liaison officers from the RAF’s Bomber and Coastal Commands, the Royal Navy, Ministry of Home Security, and the Civil Defence Association. The number of German planes brought down by anti-aircraft fire was small, however, compared to those shot down by the RAF.
Dowding, Air Chief Marshal Lord Hugh (‘Stuffy’) GCB GCVO CMG (1882–1970)
