"Is the "I" for World War ONE or World War EYE?"
The Allied forces speculated that these bikes were mainly used to power the lighting rigs in the German trenches. So the lights going out in a German trench could have two causes: either you were going to have to change a bulb, or write a letter to someone's widow. However, their green energy initiative was deemed successful enough that the Germans ported the system over to round two. Communication networks were more important than ever during World War II, so German troops were again given these tandem bicycles to power their outposts' radio systems in case their batteries or gasoline ran out. It's a shame that there isn't a single WWII movie that has a scene where the stoic U.S. sniper gets distracted during battle because he just spotted two red-faced Bavarians going to town on an exercise bike.
German National Archives
"Klaus, if you start singing 'Daisy Bell' one more time, I will shoot you."
World War I Featured Manned Kite Missions
During World War I, militaries across the globe were keenly interested in finding ways to start killing in the air. (They had already mastered earth, fire, and water.) But aviation had barely lifted off, so armies experimented with their new air forces by simply throwing stuff into the air and seeing what stuck. This was the age of biplanes, zeppelins, and, unfortunately for pilots, giant kites.
Leslie Jones/Boston Public Library
If you were thinking hang gliders, oh no no no, nothing that safe.
Means of flight were generally used for reconnaissance and battlefield observation. But giant balloons were easily popped by artillery, and planes had a tendency to just drop out of the air when someone coughed in their general direction. This led armies to experiment with kites, which were much harder to shoot down. Leaving a soldier to literally twist slowly in the wind, however, was not as high on their list of concerns. All he had to worry about was what would kill him first: a German marksman or a stiff breeze.