Systematic attention to detail has always been a basic concept of German military
theory, and the present war has proved no exception in this respect.
The original German plans for the conquest of Europe apparently hinged on the striking
power of the Luftwaffe, which believed itself to be invincible both in offense and
defense. The Polish, Norwegian, and French campaigns supported this assumption and it
was not until the Battle of Britain that it was seriously challenged. Goering had laid
great emphasis on the Luftwaffe's ability to defend German cities from enemy air attack, and
the possibility of such an attack was not really contemplated until after the failure to
destroy the RAF over England. This miscalculation as to the strength and fighting
power of the RAF forced a revision of German theories as to their own air capabilities, and
the unexpected requirements of the Russian invasion afforded the British the welcome
opportunity to create a powerful offensive air force. When the Luftwaffe found itself
fully occupied in Russia, and consequently unable to supply the necessary aircraft
for adequate defense against air attacks from the west, the road was clear for
the RAF to organize bombing operations against German cities. Ground defense against
large-scale bombing attacks thus became a German necessity, and among the methods
developed was the decoy target.
Although the object of a decoy target complements that of camouflage, the two differ
materially. Camouflage endeavors to hide the actual target--at least from visual
reconnaissance--while a decoy target is intended to be used at night to divert
bombing attacks from the real objective. Elaborate decoy systems cover most of the
large cities and industrial areas in Germany and, to a lesser extent, those in the
The German decoys consist of specially built units of varying design, usually in the
form of either large rectangles (150 by 300 feet) or circles similar in size and
appearance to oil tanks, all filled with some combustible material, and erected at
a distance, usually 2 to 5 miles from the town or target to be protected. At
night, when a raid is expected, these units or "fire sites" are ignited and resemble
large fires in built-up areas, burning buildings, or oil tanks. They stand out against
the dark landscape and invite investigation by the approaching bombers endeavoring
to locate the target. With the increased use of incendiaries, bombing crews tend to
become "fire minded" and to bomb fires in the estimated target area. This leads to
more fires and further attacks on the supposed objective, to the exclusion of the
real target. The effectiveness of such decoys is further increased by foggy or
cloudy weather, which obscures their real identity and prevents proper recognition
of ground features. Once a mistake has been made, limitations of fuel and bomb loads
make effective corrections of target errors difficult if not impossible.
A typical decoy installation protecting an important nitrogen and cyanamide plant
is shown in the following sketch. It was situated 4 1/2 miles away from the
parent target, the layout of which it resembled to some degree. The two small
and two large white circles painted on the ground (C) represent oil tanks. The
four walled rectangles (B) are fire sites and, when in action, would represent
blazing factory buildings. The two lines of parallel walls (A) are probably intended
to indicate outlines of factories. Three bomb craters are seen at (E), indicating
some successful deception. There is a collection of sheds at D which probably
houses the personnel and controls, operating the decoy.
Another elaborate installation simulates a synthetic oil refinery. A number of tanks
painted on the ground are surrounded by dummy protective walls. In the immediate
vicinity are several rectangular fire sites. A pipe line is represented by a dark
line painted over fields leading down to the shore, where there is a dummy wharf
with two lighters in the mud alongside.
The present trend of "fire sites" is to have them cover much larger areas than was
originally the case. Instead of rectangles, there are irregular block formations or
bays cut into diagonally opposed corners with dimensions as much as 630 by
350 feet. These are filled with combustible material which when afire gives the
appearance of entire blocks of burning buildings. It is often noted that gutted
areas in towns are shaped in this manner, with the streets forming fire breaks. A
different type consists of a large number of low, sloping sheds, roofed, but
without walls. Their total destruction, when bombed, suggests a fierce fire and
possibly indicates treatment of the surface with some inflammable liquid.
Numerous examples of the success of decoy operations have been noted. In one
instance, a decoy 4 miles from the actual target was clearly identified by
photographs and yet was later largely destroyed after four night-bombing
attacks. Subsequent reconnaissance disclosed a large number of bomb craters in
the vicinity. In another case, a large and effective decoy covering an
area 3 miles by 1 1/2 miles and far removed (20 miles) from the
target, a large industrial town, received most of the attack, with eight aircraft
photographing the actual bombing.
Decoys are not so useful in coastal areas, as the real targets are more easily
located. However, five decoys within a 5-mile radius of a seaport diverted
over one-third of a large number of bombers from the objective.
Decoys often take the form of fake reproductions of vital installations or areas. This
is particularly true of airdromes and landing strips, 1 decoy airdrome on an island
collecting 51 new bomb craters within 2 months. Sometimes the dummy is combined
with a "fire site." A certain German aircraft factory has such a combination located
a mile-and-a-quarter away, the dummy assembly shops being identical in size and angle
of direction with the original, and having a rectangular fire site between two of them.
The tendency of night bombers to attack fires often leads to action against "self-creating
decoys," i.e. genuine fires off the target, caused by forced jettisoning of bombs or
by incendiaries dropped after erroneous identification. In one attack, the first
wave of aircraft bombed a town 9 1/2 miles off the target and set it afire. Subsequent
groups all attacked the fires, with the result that the real objective received
little or no damage.
In favorable weather affording good identification, decoys are ineffective and may
actually be useful in locating the target when their distance and bearing from it
can be accurately estimated.