Radar has had a considerable impact on warfare since its development in the 1930s, most significantly in aerial and maritime operations. Radar (radio direction and ranging) functions by reflecting ultra-high frequency radio waves off objects back to a detecting source, thereby ascertaining the target's range, direction, and altitude. Although by the late 1930s the Germans were more technically advanced, it was the British under the aegis of Robert Watson Watt who first put radar, or RDF (‘radio direction finding’ as it was initially known in Britain), to practical operational use as part of a package of measures to provide early warning and interception capability for the RAF against the Luftwaffe prior to WW II. As Britain prepared for war a series of radar stations was set up across southern England, and radar was an important factor in the winning of the battle of Britain in 1940. Other powers were also developing radar and a critical scientific war began as each side attempted to produce new innovations that might gain a short-term advantage.
In order to avoid enemy fighters zeroed in by ground radar, bombers began using the cover of night to avoid detection, but this had been anticipated and defenders began fitting smaller short-range radar sets into two-seater night fighters. The Germans adapted a whole range of aircraft to meet the challenge of the RAF's night-time bombing offensive of 1941-5. RAF Bomber Command also developed radar equipment to aid bombing and measures to confuse German defences, the most notable example being the dropping of ‘window’, aluminium strips (an early form of ‘chaff’) designed to blind German radar. The Allies took a lead in the radar war with the development of centimetric radar which greatly increased efficiency and capability. In the final year of the war the RAF's radar-assisted bombing often proved to be more accurate than the USAAF's precision air raids using visual methods.
Radar was also used in the maritime war to hunt German U-boats both from the air and from the surface, and, moreover, proved to be an essential tool for surface fleets as early warning against air attacks. Advanced radar technology conveyed considerable advantage to US forces fighting the Japanese whose radar capability was much less developed.
Radar development post-war has enhanced navigation, bombing accuracy, and co-ordination capabilities in attack (AWACS (Airborne Warning and Command System) for example). Radar has also been an important factor in modern tactical engagement techniques with great reliance being placed on guided missiles and methods to defeat them, both passive and active. Nevertheless, radar appeared to have negated the element of surprise in conventional air attacks and much effort has been invested in defeating radar detection, the most famous and expensive example being the Lockheed F-117. Such stealth technology projects as this, the Northrop B-2, the Joint Strike fighter, and the new F-22 undermine radar by using radio-absorbent materials and low-reflective silhouettes.
Bibliography
- Bowen, E. G., Radar Days (Bristol, 1987).
- Murray, Williamson, and Millett, Allan R., Military Innovation in the Interwar Period (Cambridge, 1996)
— John Buckley
