It has been said that war is the true mother of invention. The Wright Brothers had made their famous first flight only in 1903, just eleven years before the outbreak of World War 1, but all the major countries had been quick to recognize the value of the airplane as a weapon of war. Driven by an undeclared arms race between Germany, France and Britain, all of the future combatants worked to to improve the airplane, so that by the time war came airplanes were part of the arsenals of all the major warring nations. In the next four years, the airplane would be perfected even more, so that it could fly faster, climb higher and drop more bomb loads.
However even the relatively primitive airplanes that existed at the start of the war in 1914 posed a threat to soldiers on the ground; at first, in their role as spotters and reconnaissance planes, but soon also as ground attack aircraft and bombers. It was important that soldiers could identify enemy planes so they could take cover and or fire back at them, without of course hitting friendly planes.
For this purpose, French troops deployed in Belgium at the start of the war, where the infant German airforce was particularly active, were given cards printed with the silhouettes of enemy planes and zeppelin dirigibles.
The graphic below provided illustrations of various German bi-planes:
This graphic showed the outlines of German monoplanes. It is interesting how much these planes resembled birds in terms of their shape and wing design, as nature was still the best model for conquering the air.
Finally this illustration showed the silhouette of units of Germany’s deadly dirigible fleet. In the absence of an effective interceptor force, Germany’s zeppelins could roam far and wide, dropping bombs on cities and strategic points such as railways. They did not become obsolete until later in the war.