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PMN1
27th May 2009, 21:27
From ‘Britain’s’ Shield: radar and the Defeat of the Luftwaffe’ by David Zimmerman

In 1933 Dr Rudolph Kuhnold, Chief of the German Navy’s Signals Research Division, began work on a radar detection system. The origins of this work stemmed from Kuhnold’s earlier development of an underwater acoustical device similar to modern sonar. This shows that it was possible to make the transformation from acoustical to radio detection systems. Tests on radiolocation devices began in France in January 1934 and in the Soviet Union in July of that same year.

It is more surprising, therefore, that it took until 1935 before a programme to develop radar began in Great Britain. Sean Swords, in his technical history on early radar development, managed to trace three separate suggestions, or formal proposals, for the development of similar devices dating from as early as 1926. The first of these suggestions was made on 4 August 1926 by O F Brown, a scientist with the Department of Scientific and Industrial Research, to the Anti-Aircraft Research Committee. He suggested to the committee a variety of ways that a cathode-ray oscillograph, a precursor to the CRT, could be used to enhance existing acoustical mirror technology. He added that it was ‘possible that a method of location in the azimuth could be based on the use of the cathode-ray direction-finder or short wave radiation excited in the metal of aircraft by magnetos or by secondary excitation in a strong filed emitted from a ground transmitter’. Unfortunately for Lindemann, he either did not see Brown’s paper or missed the significance of this particular suggestion. However, Lindemann, in his quest to find an alternative to acoustic mirrors, certainly pursued research into the detection of radiation from aircraft magnetos.

In 1928 L S B Alder of the Royal navy’s Signal School, proposed the development of a device ‘for the employment of reflection, scattering, or re-radiation of wireless waves by objects as a means for detecting the presence of such objects’. The device could be sued as an aid to navigation or a means to detect ‘approaching ships or aircraft’. There is no record that officials at the Signals School took any notice of Alder’s proposal.

The most extensive research by British defence scientists into using the reflections of radio waves for long range detection undertaken prior to 1935 occurred at the Signals Experimental Establishment (SEE), by W A S Butement and P E Pollard. Ironically, Pollard was under secondment to SEE from Tucker’s Air Defence Experimental Establishment. In late 1930 the two conducted a series of experiments using a short-wave radio source and receiver. Based on the results of this work, on 26th January 1931, they proposed the building of an ‘apparatus to locate ships from the coast or other ships, under any condition of visibility, or weather’. The ‘apparatus depends on the reflection of Ultra Short Radio Waves by conducting objects, e.g. ships’. SEE allowed them to conduct a limited series of experiments and they were able to detect a mast at about 100 yds away. However, here too the significance of this work was missed by both the War Office and Admiralty and the research programme was terminated.



Does anyone know any more about these proposals and how close they were to what did become RDF as we know it?

What impact would an earlier RDF have?

The RN now has good warning of incoming aircraft, what does that do for the armoured box concept?

I’ve read that Oboe MkI was derived from Chain Home Low, what does an earlier RDF do for bomber navigation –before 1939, Ludlow Hewitt was making some very accurate statements about how poor the navigation was in Bomber Command.

Groggy
28th May 2009, 09:53
What about A. M Low? He was working on Wireless ranging for guns when directed to work on guided missiles in 1914. his patents Great War patents on wire guided rockets and strategic missile were released in 1925 and subsequently the German Army started work on Rockets and Goddard’s first liquid rocket bore a resemblance to the ideas featured in the patent. He had actively successfully worked on stealth aircraft at some period during 1914~1918

ChrisMcD
29th May 2009, 11:39
I think the problem was transmitter power. Even Marconi knew that radio waves could be reflected.

IIRC Watson-Watt was asked whether a 'Death Ray' was feasible and on doing the work realised that a really powerful 'modern' that is to say 1930 vintage transmitter could achieve a realistic detection range. But to prove it he had to use the BBC World Radio shortwave transmitter at Daventry as the only source with sufficient power.
http://en.wikipedia.org/wiki/Robert_Watson-Watt

I have a feeling that the problem was in the design of adequately powerful valves that only came out in the 30's - wasn't Philips heavily involved?

Perhaps one of the electronics experts can help?

PMN1
26th March 2010, 00:01
In the middle of 1936 Eddie Bowen suggested there was no reason for the transmitter to be in the aircraft, instead the airborne receiver would utilise radio pulses from a transmitter on the ground. Bowen dubbed this radar RDF 1½, because the Chain radar was known as RDF1 and the complete aircraft mounted system RDF2.

Testing of this hybrid commended in the autumn of 1936 using a Heyford bomber. On its first flight the radar detected an aircraft at between 8 and 10 miles distant. Bowen argued that RDF 1½ worked so well that it should be adopted, rather than wait for the development of a complete airborne radar system. Watson-Watt overruled him, citing difficulties in getting accurate range measurements unless the fighter was directly between the transmitter and an enemy bomber.


Was Bowen being overenthusiastic and was Watson-Watt correct?

ChrisMcD
26th March 2010, 00:48
Was Bowen being overenthusiastic and was Watson-Watt correct?

Hi PMN1

If you want an opinion Watson-Watt suffered from a serious case of 'not invented here syndrome'.

Bowen was totally correct and his system would have avoided a lot of the detailed technical problems that haunted early AI development ( for example, the tendency of the transmitter to 'flood' the receiver without a way of rapidly switching it off, which would not have been a problem with a remote transmitter). Apart from anything else this, you could argue that this is simply an earlier application of the idea behind passive radar detectors, like Flensburg and Naxos, which were very effective.

Bowen was a great scientist and did superb work - including getting American radar research off on the right track.

curmudgeon
26th March 2010, 01:18
In the middle of 1936 Eddie Bowen suggested there was no reason for the transmitter to be in the aircraft, instead the airborne receiver would utilise radio pulses from a transmitter on the ground. Bowen dubbed this radar RDF 1½, because the Chain radar was known as RDF1 and the complete aircraft mounted system RDF2.

Testing of this hybrid commended in the autumn of 1936 using a Heyford bomber. On its first flight the radar detected an aircraft at between 8 and 10 miles distant. Bowen argued that RDF 1½ worked so well that it should be adopted, rather than wait for the development of a complete airborne radar system. Watson-Watt overruled him, citing difficulties in getting accurate range measurements unless the fighter was directly between the transmitter and an enemy bomber.


Was Bowen being overenthusiastic and was Watson-Watt correct?

There is a full history of British radar development around somewhere.

R.V. Jones 'Most secret war' has something on this as an external - he was working on infrared in the later 1930s. RDF wasn't pulsed radar (as the Germans developed and as came earlier/later) - it involved radiator and receiver systems and effectively triangulated the reflections. The non-pulsed nature fooled the German aerial reconnaissance flights along the coast by the Graf Zeppelin in mid 1939.

The SS Normandie had British pulsed radar to avoid collision at sea (c. 1936).

WW II radar, like WW II jet engines are complicated stories with lots of false starts.

Kutscha
26th March 2010, 11:30
Nice site on British radar, http://www.radarpages.co.uk/index.htm

PMN1
26th March 2010, 21:36
There is a full history of British radar development around somewhere.


Zimmerman's book gives a good history of British radar and i've just got from the library 'A Technical History of the Beginnings of Radar' by Sean Swords that goes through each country's developments.

The amazing thing about radar is how long Britain thought it had a monopoly on it and tried to keep it secret - there were still discussions in 1941 on whether Germany had radar!!!This badly affected its development in Britain as commercial firms weren't involved when they should have been.

I would say its Britain's equivalent of Germany thinking Enigma couldn't be cracked.

PMN1
26th March 2010, 21:38
Hi PMN1

If you want an opinion Watson-Watt suffered from a serious case of 'not invented here syndrome'.



Yes , that is the impression i've got from what i've read.