In the late spring of 1939, a crew of 'iron fighters' arrived at the
edge of the white cliffs of Dover and began erecting four steel towers.
The resulting structures were huge. They dominated the landscape. At
the time of construction, the school population, staff and boys, thought
they were witnessing the erection of repeater radio towers for the BBC.
In fact, they formed part of a chain of aircraft detection stations that
stretched as a chain on the east coast of the United Kingdom. To those
who organized the detection system under Sir Watson Watt, the acknowledge
inventor of British radar, the string of stations was known as the Chain
Home system, which is described in Winning the Radar War (1986)
pub. Macmillan of Canada.
By mid-summer, 1939, the Dover station at was erected and under test.
No one outside the service responsible for operating it had any inkling
of its purpose. Secret the system was perhaps, but four sky-scraper steel
towers were there for everyone to see. Even German youth groups busily
cycling from one end of the country to the other snapping holiday their
shots in the years before World War Two were unaware of their purpose.
Oddly enough, there is no record that these scouting groups ever photographed
the C-H towers though they may have done.
In 1938, the German high command brought a Zeppelin out of mothballs,
fitted it with a mass of radio sensing equipment and sent it to cruise
off the coast of the United Kingdom in search of evidence that any aircraft
locating system similar to their own. The Zeppelin found none, but it
did detect a massive and persistent noise in the 50-cycle wavelength
that interfered with their radio-listening equipment and made sophisticated
detection impossible. Knowing that the British power grid operated at
50 cycles per sec (CPS), the German listeners put the interference of
their equipment down to lousy cable joints and loose connections. The
British C-H system was safe.
Unknown to British, the Germans developed their own system of aircraft
detection about the same time that Watson-Watt and his team were working
things out at Bawdsey Manor on the Suffolk coast. The German system operated
at a high frequency. It produced a stiletto-like beam, but its range
was short, no more than with a 15 mile range at the start. Unknown to
the Luftwaffe Chief of Radio Telecommunications General Wolfgang Martini,
the British had developed a radar system. It broadcast like a ghetto
blaster at such strength and volume that its waves were detected as far
away as New Jersey in the United States. This is what the Zeppelin
listeners detected on their equipment, but ignored. Still unsure of themselves
in the final months before the war, German Telecommunications Command
made one more effort to check for British radar. They despatched the
Zeppelin across the North Sea again, just to make sure. By the time of
the second visit, the C-H system was in place and operational. The Zeppelin
eavesdroppers returned to repeat their 1938 report: no detection system;
inefficient national grid; huge radio interference in the 50 cycle range.
Following the fall of France in 1940, the Germans could stand on the
white cliffs of France and gaze across the Channel, which they did. With
advanced photographic equipment, they took an exposure of the Dover station
towers with "...a five minute exposure on an infra-red camera at
a distance of 22 miles" as recorded in the caption accompanying
a reprint of the Dover station towers image in The definite story
of the Battle of Britain – The Narrow Margin (1961) published by
Arrow books of London.
During the summer of 1939, Sergeant Major (Dusty) Miller, in charge of
physical training, despatched the entire school on a marathon as far as
the Dover station and back. The event took place once a month, on a Saturday
The same caption mistakenly reported that "The various buildings
silhouetted against the masts are, in fact, a long way in the foreground." Had
this been the case, the buildings would have been sitting somewhere out
to sea in the English Channel. As Dukies will recognize, the buildings
in question are in the school. The clock tower can be seen next to the
left hand tower along with two smaller tall buildings. Between the third
and fourth towers is A Company H-block or, as it is now known, Marlborough
House. Nor are the buildings that far away in the background.