The Battle of Britain Five Months That Changed History, May—October 1940 by James Holland (z-lib.org).epub

disposal to the defeat of the enemy Air Force.’ Sadly for the Luftwaffe,
however, Göring’s new instructions would not give them that chance. Not
yet, at any rate.
One person keenly aware of how effective massed German night bombing
might be was Dr Reginald ‘RV’ Jones, the scientific adviser at Air
Intelligence. Since his breakthrough with the German Knickebein beams,
RV had learned much more about German use of radio technology.
Decrypts of Enigma signals had alerted him to an instrument called
‘Wotan’. RV had immediately turned to his friend, Frederick ‘Bimbo’
Norman, a professor of German literature, who told him Wotan was the
king of the old German Gods and had only one eye. ‘One eye – one beam!’
Bimbo had suggested excitedly down the telephone to RV. ‘Can you think
of a system that would use only one beam?’
He could, and explained how. A plane could fly along a beam pointing
over a target, and then something like a radar station could be placed
alongside the beam transmitter, so that the distance of the bomber could be
continually measured from the starting point of the beam. When it reached
the target, the crew could be told. Soon after, RV discovered an apparatus
called ‘Freya’. Having bought a book on Norse mythology from Foyle’s
bookshop and bringing into the frame what he already knew, RV concluded
that ‘Freya’ was most likely a form of mobile radar. Once again, he was
bang on the money.
Further documents recovered from downed German bombers suggested
that a new Knickebein beam was being installed at Cherbourg and that KG
54 would soon be using it for operations to Liverpool. At the same time, RV
had begun bombing surveys to record the pattern of German bombing, and
suggested Liverpool and Birmingham for particularly careful observation.
Meanwhile, the RAF’s 80 Wing under Wing Commander Addison, working
with the Telecommunications Research Establishment at Worth Matravers
in Dorset, had begun working on Knickebein counter-measures as suggested
by RV. The first solution was to ‘jam’ the beams by transmitting a ‘mush’
of noise on the Knickebein frequencies. A more subtle solution, however,
came in the form of transmitted ‘dashes’ that sounded very like the genuine
Knickebein dash created when the two beams intersected. The idea was that
the bomber crew listening to it would think they had reached the target
earlier than was the reality, so would drop their bombs, it was hoped, before