The daily monitor leader., 1945-12-18
Luftwaffe Was Blinded by Tinsel Strips
Dropped from us. BOmbers to Jam Radar
BY s. BURTON HEATH
NEA Staff Correspondent

A'AeSSs . ~
want of some glittering strips
like those we hang on Christmas
trees, the Luftwaffe lost the bat
tie of Britain and possibly
as a result, Germany lost the
war.
The Nazis knew all about the
tinsel and what it would do to
British radar. They had a sup
ply probably ample to jam all
the radars without which the
tiny British fighter force could
not have beaten the Luftwaffe
blitz. But they didn't use the
strips and the outnumbered Raj
emerged by November, 1910, the
winner of the Battle Of Britain.
The Germans didn't use the
radar-jamming weapon because
they thought we didn't know
about it and feared to tip us
off. We, on our part, thought the
Nazis didn't know about it and
failed to employ it until mid
1943.
This latest story Of Nazi err
ror that saved democracy was
told here by scientists attached
to the Radio Research Labora-
tory at Harvard University, in
connection with the first public
description of the continuous and
effective Allied war against Axis
radar.
REFLECT WAVES
The bits of tinsel that the Ger
mans refrained from using are
what the British call by the
code name window" and we
call "chaff." A secret memoran-
dun dated in early 1914 gives
to our use of this "chaff" much
credit for the effectiveness of
Allied bombing against German
cities.
"Chaff' consists OF slim strips
of aluminium just under foot
long, wrapped in bundles of
about 5000. An alternative, used
against the Japs, is a 400-foot
roll of thin aluminium tape about
half an inch wide.
Each Allied bomber going
against Germany carried 700
bundles of 'chaff" AS the bomb
ers got into an area of danger
from ack ack or fighter patrols,
its crew would begin dropping
the packages at predetermined
intervals. Each bundle would
spread its strips in the sky,
where they would reflect Axis
radar waves exactly as though
they were planes.
Down below, German radar
had been following the unseen
bombers. showing locations and
distances, guiding fighter con-
troll and aiming anti = aircraft
guns. (See Fig. y. The clouds
of window" would fill the ra-
dar scope with SO many echoes
that the Nazis would be driven
to guess what was happening
in the sky. (See Fig. ID.
JAMMED RADAR
Military aviation experts say
that if Goering had used "chaff'
to jam British radar in the blitz
period, right after the fall of
France, Hitler would have won
the war then and there.
We used "spot jamming" mi
cro-wave electronic devices so
effectively in the invasion of
southern France that we knock
ed out Germa radar completely.
We used "chaff" in the invasion
of Normandy so cleverly that we
kept the German fighter reserve
flying blindly, far from the in
vasion point, until they ran out
of gas.
The use Of, "chaff' or Of MI
cro-wavc electronic jamming de-
vices makes radar gun-pointers
virtually worthless. Newsmen
stood beside modern gum
pointing radar here and watch
ed the antenna swing helplessly
back and forth while planes
dropped "chaff" - but come to
firm point as soon as the jam
ming stopped.
Against Nazi night fighters,
the Allies often sent decoy for
nations of window dropping
fighters, who simulated the pres
ence of large bomber groups
here and there, so that the Luft-
waite had to split up its defend.
ing planes instead of being able