Radar from Little Acorns

There was an understanding that if war did come, then 'the bomber' would be the principal offensive weapon that would be used against Britain. As an island, Britain was marginally less vulnerable to invasion than her European neighbours. Nevertheless, one or two senior officials were suggesting that the defence of the nation should be given urgent consideration and that perhaps new or scientifically novel methods should be employed.

Stanley Baldwin had stated in 1932 that "the bomber will always get through" and that straightforward human observation followed by fighter interception was going to be the best defence. However, in overcast conditions, estimating the range and altitude (and even the direction) of an enemy force was almost impossible. So how would it be possible to make sure that the fighters could intercept the enemy bombers before they could drop their bombs?

Aircraft spotters from the volunteer Observer Corps on duty

Professor Lindemann (later Lord Cherwell) argued for the development of barrage balloons and the use of aerial mines as a primary means of defence but that would presuppose that the enemy bombers had already arrived overhead. He was to prove to be a disruptive influence during the formative period of RDF development but fortunately his views did not prevail.

It was appreciated that it was unreasonable to expect a standing force of fighters to be in the air 24 hours a day and even if that were possible; would they be in the right place? Other lines of research included the development of very powerful searchlights, acoustic listening devices and specialised anti-aircraft guns.

The real need was for some method of early warning. Such a capability would allow the maximum effort to be applied in a specific and economical way. It would also reduce the potency of an enemy attack.

A system that could 'see' through clouds and could penetrate the far distant sky for perhaps 100 miles seemed like impossibility. A few farsighted men thought differently…

The story of Radar development is a complex one and like so many advances in human skills, was not the work of one man. In fact this story is made up of many discoveries made over a 60-year period, in at least 7 countries.

In 1888 Heinricht Hertz demonstrated that electromagnetic waves were radiated at the speed of light.

In 1904, Christian Hulsmeyer built a 'telemobiloscope' that could detect ships at distances of 3 km. The Marconi Company had been active in radio and radio direction finding equipment since 1912 and in 1922 Marconi was advocating that ships should be navigated using radio direction techniques. The French liner ' Normandie' was fitted with a "radio obstacle detector" in 1934.

The great achievement of the British scientists was to synthesize all these ideas into one practical, operational and precise technology…and to do it very quickly…

Radar Recollections - A Bournemouth University / CHiDE / HLF project

Radar from Little Acorns