Robert Alexander Watson-Watt convinced the Air Ministry that his radar set had merit. Good thing for Old Blighty.

Courtesy Archives of Ontario 1935: The feasibility of radar is demonstrated for the British Air Ministry. It would prove to be a just-in-the-nick-of-time apparatus that helped save Great Britain from defeat in World War II.

Radar (for RAdio Detection And Ranging) was developed over the years with input from many sources, but it was Robert Watson-Watt, a Scottish physicist looking for a reliable method to help airmen locate and avoid approaching thunderstorms, who designed the first set put into practical use. Watson-Watt realized, as he perfected his device, that radio waves could be used to detect more than storms.

A Royal Air Force Heyforth bomber was used for the War Ministry demonstration at Daventry. Three times the plane passed overhead and three times the main beam of a BBC short-wave radio transmitter picked up reflected signals.

Impressed, the air ministers embraced the new technology and by September 1939, when war broke out in Europe, the British had a network of radar installations covering the English Channel and North Sea coasts.

It was radar, even more than the pluck of the dashing RAF pilots, that tipped the scales in England's favor in the Battle of Britain.

Hitler's strategic aerial onslaught, meant to clear the skies over the Channel and southeastern England preparatory to an invasion of the British Isles, might have succeeded if not for radar. The RAF was outnumbered by the Luftwaffe, and radar saved already-stretched Fighter Command from having to maintain constant air surveillance.

With radar providing an early-warning system, well-rested RAF pilots could be scrambled and rising to meet the incoming enemy formations in a matter of minutes. As the German fighters ran low on fuel and were forced to turn back, the Spitfires and Hurricanes could pick off the German bombers as they moved deeper into England.

The battle peaked during September and October 1940. The Germans, discouraged by their tactical errors and high losses, gradually tapered off their attacks, then abandoned them altogether when Hitler turned his attention to Russia.

An interesting historical footnote: Although radar was introduced to warfare by the British, the Germans developed their own version and used it effectively during the Allied air raids over occupied Europe and the Reich.

(Source: Various)

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