German Decoy Targets, WWII Tactical and Technical Trends, No. 17, January 28, 1943 (Lone Sentry)

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 occupied countries.

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.

[German Decoy Target]

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.