Osprey's examination of German air forces of World War I (1914-1918). The Imperial German Army Air Service of World War I grew from just 500 men in 1914 to 80,000 in 1918, inventing in the process a wholly new form of warfare. The exploits of the first fighter 'aces' have been widely celebrated, and have tended to overshadow the other, equally important branches of the fighting air forces - the reconnaissance and ground attack units, the airships...