Defending the Nation

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Radar
Radio Direction Finding
Defending the Nation
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Radar Timeline
Radar Facts
Radar Diagrams and Activities
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Radar in the Pacific detected Japanese planes
that were about to attack the U.S. naval base at
Pearl Harbour. The signals were ignored!
Radar Interesting Facts
Aluminium strips were dropped by British aircraft
while bombing Hamburg. These strips caused severe
interference on German radar screens.
The British began experiments using RDF (radio
direction-finding) equipment.
17 new radar stations were added to the Chain
Home stations along the English coast.
1935
1945
1937
1939
1941
1943
Radar Jamming sets were used extensively during
the build up to D-Day, making it difficult for
the Germans to detect when and where the invasion
would take place.
The Biggin Hill Experiment. Practical tests of
radar made with the R.A.F.
August, 1940. The Lufftwaffe target radar
stations in an attempt to blind Britain.
The German Navy created a workable radar set in
1934.
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The "Radar Stations" were Britains first line of
defence. They helped to detect enemy aircraft
before they reached the British Isles. Signals
would be beamed across the English Channel from
radio transmitters. These signals would be
bounced back to radar receiving stations. Enemy
aircraft were shown as blips on a radar screen.
These blips could give a fairly accurate
picture of the size, position, height and
distance from the British coastline of any enemy
raid.
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How Radar Works A transmitter gives out a radio
signal into the air in short bursts. If the
signal meets an object (an aeroplane) the radio
signal will be reflected back to a receiver. This
will show up on a radar screen as a jump, or
peak, on a long flat line. From this the
approximate direction, distance and height of
aircraft could be calculated. This information
was passed on to the Operations Room. Fighter
Planes were scrambled and a Fighter Controller
would then direct those planes to the target.
Target Echo Pulse Over the 60 mark means the
aircraft are 60 miles away.
20
40
60
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Click on the screen to follow the flow of
information
Information received from radar receiving stations
Filter Room at Fighter Command HQ begins to plot
the enemy raids
Information is passed to Group Headquarters
The Observer Corps pass on additional information
to Controllers as enemy aircraft are sighted
Squadrons are scrambled as necessary and guided
to enemy aircraft by Controllers
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Radar masts had receiver aerials that could be up
to 350ft-high.
The masts, although appearing fragile, presented
a difficult target for the Luftwaffe to hit.
Dover Chain Home Station
Radar stations aimed to pick up signals over the
English Channel.
Radar was originally called RDF Radio
Direction Finding.
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Radar Stations, not surprisingly, became a key
target for the Luftwaffe during the Battle of
Britain.
12th August 14 Luftwaffe Bf109s attacked radar
stations that included
Pevensey, Rye, Dover and Ventnor.
These were difficult targets to hit
because of their small size. Three
out of the four stations were fully
operational again by the end of
the day.
15th August Once again, Pevensey and Rye Radar
Stations were affected when
Luftwaffe bombs severed main power lines.
Foreness Radar Station
suffered the same fate and all three stations
were out of action for
most of the day.
16th August Goering decreed that no further
effort should be wasted on attacking
British radar stations. This seems a
fateful decision, but Goering was
determined to put all of his efforts into
targeting Britains main
airfields instead in view of the fact that not
one of those (radar stations)
attacked has so far been put out of action.
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Can you mark on the direction of flow of
information?
Airfield
Observer Corps
Group HQ Sector Operations Room
Fighter Command HQ
Radar Stations
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Can you mark on the direction of flow of
information?
Airfield
Observer Corps
Group HQ Sector Operations Room
Fighter Command HQ
Radar Stations
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Place the correct information into the empty
boxes.
Radar was originally known as Radio Direction
Finding
Radar Stations
These could often estimate size, position, height
and distance of enemy formations
Radar Masts
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What can you remember about Radar and how it was
used during World War Two?
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Write a short paragraph. Describe the defensive
system that existed to protect Britain from air
attack?