The Chain Home Network
Courtesy of Picryl.The Chain Home, the first radar, was built in the years leading up to war, providing the British with a warning of approaching aircraft.
I. A Rising Urgency for an Early Warning System
In 1933, Hitler was appointed Chancellor of Germany, and was quick to express his desires to expand the German territory, and later to support the Nationalists when the Spanish Civil War (1936-1939) broke out.
“Hitler and Mussolini jumped in on the side of Francisco Franco and his Spanish Nationalists, sent them vast amounts of military aid, airplanes, tanks....it really was the opening act of World War II... This war was a testing ground for Hitler. And he learned a great deal from it about the strengths and weaknesses of these different weapons.”
- Adam Hochschild, American Journalist and Historian, Author of Spain in Our Hearts, in an Interview with NPR
RPReplay_Final1702841009.movHitler arrives and takes position on a platform, giving a Nazi salute as German troops who fought for fascist dictator Franco of Spain parade by.
Courtesy of Historic Films.
RPReplay_Final1702841309.movExcerpt from Spanish Nationalist insurgents attack Madrid (1936)
Courtesy of Reuters.
“Under [Hitler's] guidance, the Nazis took a firm grip of the political and military life of [Germany]. Germany's military strength built up at an unprecedented rate and a formidable air force was in the making. No attempt was made to conceal these developments...
Nazi Germany, circa 1936: German rearmament in the 1930's shows the German air force and troops, the former being made into the feared German Luftwaffe.
Courtesy of Popperfoto via Getty Images.
“In Britain there was a very mixed reaction to these events. A few people were thoroughly alarmed, but the great majority were unmoved and apathetic...[However, Henry] Tizard was in a unique position to consider the problem of Great Britain's air defense.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
New York Times, March 12, 1935.
Courtesy of Rare & Early Newspapers
Circa 1940: German aircraft factory.
Courtesy of Roger Viollet via Getty Images.
Circa 1943: German factory Heinkel of "HE III" bombers.
Courtesy of Roger Viollet via Getty Images.
II. The Invention of Radar
Sir Henry Tizard
Sir Henry Thomas Tizard (1885-1959) - English chemist, inventor, and Rector of Imperial College
Courtesy of Mary Evans Picture Library.
“[Tizard] was the Rector of Imperial College, a position which gave him leisure to think about the problems England would soon have to face and ready access to governmental and military circles in London... He realized that in a few years' time Britain would be subjected to a devastating air attack and, as things stood, the country was defenseless against it.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
“[Before radar] they wouldn't know where any of the bad guys were, and they would scramble and then fly around and there's all this chaos [because they couldn't find the bomber] ...and the bomber will always get through. That was the standard; that bombers are invincible.”
- Lt. Col. Randall DeGering, USAF (ret.)
“[Tizard believed] that both aircraft and anti-aircraft guns could be made effective against such an attack, but only if they were in the right place at the right time. In other words, warning of approach of enemy aircraft was a critical requirement coupled with a precise indication of where the enemy aircraft were at any particular moment and where they were headed.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
An anti-aircraft gun battery. The 4.5-inch was one of two medium anti-aircraft guns used by the Royal Artillery during the Battle of Britian.
Courtesy of the Royal Air Force Museum.
As Tizard raised alarms, he formed a committee to brainstorm ideas for defensive technologies.
Sir Robert Watson-Watt
The "father of radar in England" (1892-1973).
Courtesy of Popperfino via Getty Images.
“One idea which appeared to have a special fascination for the Air Ministry was the concept of a death ray which would either claw an aircraft out of the sky or burn up the occupants at the turn of a switch...[this] was sent to Watson Watt at Slough for an assessment...
“[Watson-Watt's staff realized] that if radio waves were sent in the direction of an approaching aircraft, while no damage would be done, there was a possibility of doing something quite different, namely detecting the radio waves reflected back from that aircraft.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
'The First Step' - A painting by Roy Huxley, depicting the Daventry radar experiment in a field in Litchborough, England.
Courtesy of the Daventry Museum.
Birth of Radar Memorial plaque in Litchborough, England.
Plaque reads: "Brith of Radar Memorial: On 26th February 1935 in the field opposite, Robert Watson Watt and Armold Wilkins showed for the first time in Britain that aircraft could be detected by bouncing radio waves off them. By 1939 there were 20 stations tracking aircraft at distances up to more than 100 miles. Later known as radar, it was this invention, more than any other, that saved the RAF from defeat in the 1940 Battle of Britain."
Courtesy of the Daventry Museum.
“[This] was the trigger which began a whole sequence of events which were to have a profound effect on the conduct of war, and which continues to do so to the present day.....
“Britain...faced a serious threat and was forced to take action. It was the Tizard Committee which defined the problem in a clear way and expressed the need for early warning of the approach of enemy aircraft and it was Watson Watt who suggested the solution...What was even more important, the merit of the proposal was recognized by the Government in 1935 and acted upon.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
Bawdsey Manor and the broad expanse of Manor ground, which, during World War II was the Air Ministry's secret radar research establishment where the scientists responsible for the development of radar lived and worked from 1936-1939.
Courtesy of Women in the War.
This was the beginning of the Chain Home Radar.
III. Building the Chain Home System
“By 1934... we were fortunate in having a flourishing radio industry... A wide variety of well-designed radio receivers had become available from a large and professional radio manufacturing industry... [and] intercontinental radio communication by short-wave radio was highly developed.”
- Colin Latham and Anne Stobbs, radar instructor, and radar operator (respectively), in their book Radar: A Wartime Miracle
The 360ft transmitter towers at Bawdsey Chain Home radar station, Suffolk, May 1945.
Courtesy of Imperial War Museums/Flt. Lt. Goodchild, Royal Air Force official photographer.
“Watson Watt's memorandum spelled out... that a practical scheme of air detection required a measurement of the range of an approaching aircraft. A precise method of doing this was already available from previous work on the ionosphere.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
“With this level of proven technology to hand and war clouds gathering over Europe, it was natural to seek a radio solution to the feared threat of attack by German bombers. Little faith could be placed in our existing early-warning devices - feeble sound locators.”
- Colin Latham and Anne Stobbs, radar instructor, and radar operator (respectively), in their book Radar: A Wartime Miracle
Tracking Aircraft Before Radar:
Translation: The Little Inventor: The Shape of Life to Come
1928 France
Courtesy of Mary Evans Picture Library.
A four horn acoustic locator in England, 1930s. There are three operators, two with stethoscopes linked to a pair of horns for stereo listening.
Courtesy of Rare Historical Photos.
A pair of enormous amplifiers used by the US Naval Air Service for locating and contacting airplanes by day and night, 1925.
Courtesy of Rare Historical Photos.
“[Our] success [in research] prompted the Air Staff to ask for a set of five stations to provide air warning over the approach to the Thames estuary and, to their eternal credit, the Treasury earmarked a sum of £1,000,000 for this purpose. The date was December 1935 and... this was the step which consolidated Britain's lead in the technology of air defense.”
- Edward George "Taffy" Bowen in his book Radar Days, Welsh Physicist, assistant to Robert Watson-Watt
“They had these big 300-foot-tall towers with antennas 20 miles apart all the way along the coast, radiating out radio frequencies that would reflect off of any kind of airplane and give them an idea of...something coming at [them].”
- Lt. Col. Randall DeGering, USAF (ret.)
By April 1939, 29 Radio Detection Finding (RDF) stations were in constant operation, keeping watch over the Channel .
Chain Home at RAF Poling, West Sussex.
Courtesy of Imperial War Museums/Wikimedia Commons.
The Cost of the Chain Home
£ 456,300 (1940)
£ 28 million (today)
“It was 20 June 1939 - just another busy day of research and development at Bawdsey. But arriving in our various labs, we found a message awaiting us... 'Mr. Winston Churchill who is interested in the air defense of Great Britain will visit Bawdsey today.'... Churchill arrived, and the Bawdsey CH was demonstrated, an interception flown and lively discussions held on our future plans. Following lunch in the mess, Churchill addressed us, and after fifty-five years I still recall the essence of his speech:
“'Today has been one of the most exciting days of my life, for you have shown me the weapon with which we shall defeat the Nazis.'”
- Sir Edward Fennessey, Electronics Engineer under Watson-Watts, in C. Latham and A. Stobbs' book Radar: A Wartime Miracle
Radar Cover
September 1939 and September 1940
Courtesy of British Official Histories.
The RAF benefited the most from radar because it was used in night fighting, combatting U-boats, essential tools for aerial warfare, augmenting the accuracy of locating targets, and playing a crucial role in the Battle of Britain.
Integrating radar into the military transformed the capabilities of the Allies, giving them a technological advantage while established a new necessity for modern militaries around the globe - radar.
The Radio Locators are maintained by highly skilled radio mechanics and manned by RAF and WAAF Radio operators. Part of the intricate system which comprises each of these nerve centers of Britain's air defense is illustrated in this series of photographs. A scene in an RAF Operations Room at Headquarters Fighter Command, Bentley Priory, Middlesex. June 1941.
Courtesy of Memory Lane Galleries.
A Chain Home Receiver Room, August 15, 1945.
Courtesy of Memory Lane Galleries.
WAAF radar operator Denise Miley plotting aircraft on the CRT (cathode ray tube) of an RF7 Receiver in the Receiver Room at Bawdsey Chain Home.
Courtesy of the Imperial War Museum.
“They had these big control centers and they had gals with headphones on, pushing sticks across the map and getting updates every five minutes. And that was the way that they plotted where the Luftwaffe was coming from up in Denmark or across from France...you could get a clear look up on that third story, look down at the table and say, 'Okay, it looks like they're coming from this area...scramble those fighters.'”
- Lt. Col. Randall DeGering, USAF (ret.)