Robert Watson-Watt: The Father of Radar Technology in World War II

The Father of Radar Technology

Do you have any idea how airplanes navigate the sky at night?

It is truly a mystery how you can arrive at your destination safely and sound unless you uncover the most powerful tool in the aviation industry.

Today, every commercial airliner's flight path is detected by radar, or radio detection and range, to keep passengers safe. But it was created during World War II when the threat of enemy planes on the move became more severe.

Let’s explore Sir Robert Watson-Watt’s for pioneering the technology that helped win the Battle of Britain.

Early Years of Robert Watson-Watt

On 13 April 1892, Robert Alexander Watson-Watt was born in Brechin, Angus, Scotland. Robert is the son of Patrick, a carpenter and cabinetmaker, and Mary.

Robert Watson-Watt claimed to be a descendant of James Watt, the engineer, and inventor whose steam engine improvements were critical in the industrial revolution.

Watson-Watt’s Education

After finishing his school of basic education at Damacre Primary School and Brechin High School, Robert Watson-Watt attended University College, Dundee (originally part of the University of St Andrews and later became Queen's College, Dundee in 1954, then the University of Dundee in 1967).

Elijah McCoy, the inventor of the oil drip cup, also studied in Scotland but at the University of Edinburgh.

In 1910, Watson-Watt was a brilliant student, receiving the Carnelley Prize for Chemistry and a class medal for Ordinary Natural Philosophy.

Professor William Peddie gave him an assistantship after finishing his BSc in engineering in 1912.

Who was Professor William Peddie? Professor William Peddie held the Chair of Physics at University College, Dundee, from 1907 to 1942. Peddie was a Scottish physicist and applied mathematician, best known for his research contributions to color vision and molecular magnetism.

Peddie was the one who persuaded Watson-Watt to study radio, or wireless telegraphy, as it was known at the time, and taught him about radio frequency oscillators and wave propagation, which was a postgraduate course.

Early Career of Robert Watson-Watt

During the outbreak of World War I, Watson-Watt was working in the Engineering Department of the college. In 1916, Watson-Watt sought employment with the War Office but had no obvious job opportunities.

Robert Watson-Watt joined the Meteorological Office instead, which was intrigued by his idea of using radio to detect thunderstorms. As lightning ionizes the air, it emits a radio signal, and his purpose was to use this signal to alert pilots of oncoming thunderstorms. 

The signal has a wide frequency range and would be easily intercepted and amplified by naval long wave devices. Watson-Watt began employing rotating directional antennas to locate these short-lived signals since determining their location was challenging. Indeed, lightning constituted a significant issue for communications at these standard wavelengths. These revelations piqued people's interests.

Watson-Watt’s Early Experiments

Robert began his career at the Air Ministry Meteorological Office's Wireless Station at Aldershot, Hampshire. When the War Department informed him they wanted to retake their Aldershot location, he relocated to Ditton Park near Slough, Berkshire, in 1924.

His early experiments effectively detected the signal and rapidly demonstrated that he could do it at ranges of up to 2,500 kilometers. He began utilizing oscilloscopes to show the output of the antennas in 1923.

The operator would rotate the antenna in search of spikes caused by lightning that would indicate the storm's direction. Rotating a loop antenna to maximize (or minimize) the signal, thus pointing to the storm, was used to establish location. 

Because the impacts were so brief, turning the antenna in time to detect one positively was impossible. Instead, the operator would listen to many strikes to get an approximate average location.

The National Physical Laboratory was already using this location and possessed two essential instruments that would be pivotal to his research.

Adcock Antenna

The first was an Adcock antenna, a four-mast system that determined signal direction by phase variations. One could simultaneously measure the lightning movement on two axes using two of these antennas at right angles. Displaying the transient signals was a challenge.

The WE-224 oscilloscope, newly obtained from Bell Labs's second instrument, solved this problem. A single strike triggered the emergence of a line on the display, showing the direction of the strike by feeding the signals from the two antennas into the X and Y channels of the oscilloscope. The comparatively slow phosphor of the scope only enabled the call to be read after the strike had happened. 

Watson-Watt's new approach was in use in 1926 and was the subject of a lengthy paper by Watson-Watt and Herd.

Heaviside Layer

In 1927, the Met and NPL radio teams merged to become the Radio Research Station, with Watson-Watt as director. Throughout their investigation, the groups became interested in the sources of static radio signals. They discovered that most of it could be explained by distant signals reflected off the upper atmosphere above the horizon. This was the first clear confirmation of the actuality of the Heaviside layer, which had previously been suggested but ignored mainly by engineers.

Robert Watson-Watt, Edward Appleton, and others created the 'squegger' to create a 'time base' display, which caused the oscilloscope's dot to travel smoothly around the display at a breakneck speed to calculate the height of the layer. The layer's altitude could be established by timing the squegger such that the dot reached the far end of the display simultaneously as predicted signals reflected off the Heaviside layer. The development of radar relied heavily on this time-based circuit.

Watson-Watt was appointed Superintendent of NPL's Radio Department at Teddington after another restructuring in 1933.

RADAR

During World War I, the Germans utilized Zeppelins as long-range bombers over Britain, and defenses failed to keep up. Since then, aircraft capabilities have significantly advanced, and the threat of extensive aerial bombing of residential areas has caused government anxiety. Heavy bombers could now approach heights that anti-aircraft weapons of the day couldn't reach.

With enemy airfields possibly only 20 minutes flying time away, bombers would have dropped their bombs and returned to base before any intercepting fighters could reach height. The only solution appeared to be to have standing patrols of soldiers in the air, but with a fighter's short cruising duration, this would necessitate a massive air force. An alternative answer was urgently required. In 1934, the Air Ministry established the CSSAD (Committee for the Scientific Survey of Air Defence), led by Sir Henry Tizard, to investigate methods to enhance UK air defense.

Rumors that Nazi Germany had invented a death ray capable of taking downtowns, cities, and people using radio waves were brought to the attention of Harry Wimperis, Director of Scientific Research at the Air Ministry, in January 1935. Wimperis approached Watson-Watt and asked if radio could be used to create a death ray in response to German claims, particularly for use against aircraft.

Watson-Watt quickly returned a calculation by his young colleague, Arnold Wilkins, showing that a device of this kind could not be constructed; however, fears of a Nazi version soon disappeared. Earlier in the report, Wilkins suggested that radio waves might be able to detect aircraft after hearing about the plane disturbing shortwave communications.

Wilkins's idea, checked by Watson-Watt, was promptly presented by Tizard to the CSSAD on 28 January 1935.

Aircraft Detection and Location

Watson-Watt wrote a classified document to the Air Ministry on February 12, 1935, titled Detection and location of aircraft using radio means. Although not as spectacular as a death ray, the concept had potential. Still, the Air Ministry required a demonstration showing that an aircraft could reflect radio waves before providing money.

This was completed on February 26th and comprised of two receiving antennas positioned around 6 miles (9.7 km) distant from one of the BBC's shortwave transmission sites in Daventry. The two antennas canceled signals traveling straight from the station, while signals entering from other angles were accepted, diverting the trace on a CRT indicator (passive radar).

This test was top secret that only three individuals saw it: Watson-Watt, his colleague Arnold Wilkins, and a single committee member, A. P. Rowe. The experiment was successful: the receiver displayed a crisp return signal from a Handley Page Heyford bomber flying near the spot multiple times.

Prime Minister Stanley Baldwin was kept in the dark about radar advancements. Watson-Watt got a patent on a radio apparatus for detecting and identifying airplanes on April 2, 1935.

Wilkins departed the Radio Research Station in mid-May 1935 with a small group that included Edward George Bowen to do more research at Orford Ness, an isolated peninsula on the Suffolk coast of the North Sea.

By June, they were identifying airplanes from a distance of 16 miles (26 kilometers), sufficient for scientists and engineers to halt all development of rival sound-based detection systems. The range had increased to 60 miles (97 kilometers) by the end of the year, at which point preparations were formed in December to put up five stations covering the approaches to London.

One of these stations was to be built near Orford Ness on the coast, and Bawdsey Manor was chosen as the central destination for all radar research. Watson-Watt and his team developed devices utilizing existing components rather than building new features for the project to have a radar defense in place as soon as possible. In addition to polishing and enhancing the devices, the team did not take any additional time.

The prototype radars were placed into production as long as they were in working order. They ran "full scale" experiments on a fixed radar radio tower system, seeking to detect an oncoming bomber by radio signals for intercept by a fighter. The tests were a total failure, with the soldier only sighting the bomber after it had past its intended target. The issue was not with the radar but with the flow of information from trackers in the Observer Corps to fighters, which required numerous stages and was extremely slow.

Henry Tizard, Patrick Blackett, and Hugh Dowding jumped right into the challenge, inventing a "command and control air defense reporting system" with many levels of data that were finally routed to a single massive room for mapping. Observers observing the maps would then control the combatants' actions through direct communications.

It is important to note that Britain was not the only country developing radio technology in the years preceding World War II. Still, Watson-Watt pioneered the early systems known as Radio Detection Finding before the American acronym RADAR was coined (Radio Detection And Ranging).

By 1937, the first three stations had been completed, and the related system had been tested. The results were promising; therefore, the government quickly ordered the building of 17 more stations. This evolved into Chain Home, a series of fixed radar towers on England's east and south coastlines. A radar system capable of detecting enemy aircraft at any time and in any weather condition had been installed along England's south and east coasts by the autumn of 1938.

At the beginning of WWII, 19 were ready for the Battle of Britain; by the end, more than 50 had been built. Allied Forces regarded the system as a 'secret weapon' at the time. Chain Home's construction was known to the Germans, but its purpose was unclear.

They tested their theories aboard the Zeppelin LZ 130 but concluded they were a new long-range naval communications system. The RAF intercepted Luftwaffe pilots over France after receiving warnings of Luftwaffe formations over France. Without Watson-Watt's influence, such a system might not have been implemented in time.

It was understood as early as 1936 that if the day campaign did not go well, the Luftwaffe would resort to night bombing. Watson-Watt had tasked another member of the Radio Research Station's staff, Edward Bowen, with building a fighter-capable radar. Night-time optical detection of a bomber was excellent to around 300 m, and existing Chain Home systems simply lacked the precision required to get the fighters that close.

Bowen determined that an airborne radar should not weigh more than 90 kg (200 lb), have a volume of no more than 8 feet 3 (230 L), and use no more than 500 watts of electricity. The operational wavelength must not be much larger than one meter to decrease the drag of the antennas, which was problematic for the day's electronics. However, by 1940, Airborne Interception (AI) had been mastered and was vital in bringing the 1941 Blitz to a conclusion. Watson-Watt's use of a non-optimal frequency for his radar was justified by his oft-quoted "cult of the imperfect."

Civil Service Trade Union Activities

Between 1934 and 1936, Watson-Watt served as president of the Institution of Professional Civil Servants, which is now part of Prospect, the "professionals' union." The union speculates that he was active in a drive to enhance wages for Air Ministry employees at the time.

Contribution to Second World War

In an English History 1914-1945, historian A. J. P. Taylor praised Watson-Watt, Sir Henry Tizard, and their radar-development colleagues, crediting them with being critical to victory in World War II.

Watson-Watt departed Bawdsey Manor in July 1938 to become Director of Communications Development (DCD-RAE). Sir George Lee took over as DCD in 1939, and Watson-Watt became Scientific Advisor on Telecommunications (SAT) to the Ministry of Aircraft Production, visiting the United States in 1941 to advise them on the significant deficiencies in their air defense, as demonstrated by the Pearl Harbor assault. In 1942, George VI knighted him, and in 1946, he won the US Medal of Merit.

The UK government granted Watson-Watt £50,000 ten years after being knighted for his contributions to radar research. Sir Robert Watson-Watt founded a consulting engineering practice and emigrated to Canada in the 1950s and eventually to the United States, where he released Three Steps to Victory in 1958. 

Around 1958, he participated in the American television show, To Tell The Truth as a mystery challenger. Watson-Watt was allegedly pulled over for speeding in 1956 in Canada by a radar gun-toting cop, whose remark was, "Had I known what you were going to do with it, I would never have invented it!".

He wrote an ironic poem ("A Rough Justice") afterward,

Who really is the father of radar?

The debate about this title has risen over the years for Nikola Tesla being the originator of radar. Nikola Tesla is a scientist and genius most notable for wireless inventions.

It is no wonder if this has come across his mind when his list of inventions goes on and on. However, he was never recognized or credited for a few vast inventions that changed the world.

In 1917, Nikola Tesla actually presented his idea of radar to the United States Navy at the beginning of World War I. But Tesla and Edison’s feud played a role in why this idea never got invented.

In 1935, Robert Watson-Watt was declared the inventor of the radar for being the first to materialize radar and introduce this invention to the world.

Honors‍ of Robert Watson-Watt

His contribution to World War II did not help the UK’s war and modernized the entire world. Below are notable honors and recognition Robert Watson-Watt received:

• 1941 - Robert Watson-Watt was made a fellow of the Royal Society of London.
• 1942 - George VI knighted Sir Robert Watson-Watt for his invention of radar and contributions to World War II.
• 1945 - Sir Robert Watson-Watt was invited to deliver the Royal Institution Christmas Lecture on Wireless.
• 1946 - He was awarded the United States Medal of Merit, the Royal Society's Hughes Medal, and the Franklin Institute's Elliott Cresson Medal.
• 1949 -  The University College, Dundee, established a ​​Watson-Watt Chair of Electrical Engineering.
• 2013 - Sir Robert Watson-Watt became one of four inductees to the Scottish Engineering Hall of Fame.

Robert Wats‍on-Watt Legacy

Many benign applications for radar technology were discovered after the war. Air traffic controllers now rely on radar to keep commercial airplanes from colliding.

Radar is necessary for weather forecasting. In microwave ovens, the cavity magnetron is currently employed to cook food. According to reports, many motorists, including Sir Watson-Watt himself, have been caught speeding by police radar guns.

Sir Robert Watson-Watt, the inventor of radar, has been honored with a statue at Brechin. Princess Royal inaugurated a statue on September 3, 2014. The statue was unveiled to commemorate the outbreak of World War II.

The town's Robert Watson-Watt Society erected the statue. It took the organization eight years to gather funding for the statue, which is the only tribute to Watson-Watt aside from a plaque in Daventry commemorating the first successful radar test.

Other notable geniuses during wartime were Alan Turing, Karl Elsener, and Charles Goodyear who were credited with their individual contributions that led to winning the war.

The Watson-Watt auditorium is a briefing facility at RAF Boulmer named after him.

Watson-Watt was named on a memorial honoring the birth of radar at Stowe Nine Churches.

A memorial at the site of the first successful RADAR experiments in Daventry.

Watson-Watt's radar technology was dubbed Britain's "secret weapon" during the war and was credited with winning the Battle of Britain. Eddie Izzard starred as Watson Watt in the BBC Two drama Castles in the Sky a day later.

The National Library of Scotland maintains a collection of Watson-correspondence Watt's documents. The University of Dundee's Archive Services also has a collection of Watson-Watt-related papers.

Personal Life‍ of Robert Watson-Watt

Robert Watson-Watt married Margaret Robertson, the daughter of a draughtsman, on July 20, 1916, in Hammersmith, London; they divorced, and he remarried in 1952 in Canada. Jean Wilkinson, his second wife, died in 1964.

After the war, Sir Robert Watson-Watt worked as a government adviser and leader of delegations to international meetings and as an independent technical consultant in Canada and the United States. In the 1960s, Robert returned to Scotland.

In 1966, at 74, he proposed to Dame Katherine Trefusis Forbes, who had also played an essential part in the Battle of Britain as the founder Air Commander of the Women's Auxiliary Air Force, which supplied radar-room operators.

They shared a residence in London during the winter and "The Observatory," Trefusis Forbes' holiday home in Pitlochry, Perthshire, during the summer. They were married until his wife Katherine’s death in 1971. Watson-Watt died in Inverness in 1973, at the age of 81. Both are buried in Pitlochry's Episcopal Church of the Holy Trinity graveyard.

‍Key Takeaways: Robert Watson-Watt ‍

Coming up with a brilliant idea out of thin air in a time of tremendous need genuinely deserves praise and admiration. It’s comparable to how magicians present you with nothing and suddenly… ta-da! Transformed a phantom kernel into a tangible reality.

During World War II, radar arrays offered the Royal Air Force a significant advantage in detecting and repelling the Nazi Luftwaffe. The Luftwaffe would have destroyed Britain if Sir Robert Watson-Watt, a former weatherman, hadn't had a few suggestions and would not have been able to be stopped by the RAF. 

We can imitate Sir Robert Watson-Watt for having the grit to take on new and complex challenges and believing in our capabilities. The first spark for a project or organization can develop to become something significant, far-reaching, and impactful, just like a single match can light a magnificent, awe-inspiring fire.

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