The Deutsche Luftstreitkräfte (German: [ˈdɔʏtʃə ˈlʊftˌʃtʁaɪtkʁɛftə], German Air Force)—known before October 1916 as the Fliegertruppen des deutschen Kaiserreiches (Imperial German Flying Corps) or simply Die Fliegertruppe—was the World War I (1914–18) air arm of the German Army, of which it remained an integral part. In English-language sources it is usually referred to as the Imperial German Air Service, although that is not a literal translation of either name. German naval aviators serving with the Marine-Fliegerabteilung remained an integral part of the Imperial German Navy (Kaiserliche Marine). Both military branches, the army and navy, operated conventional aircraft, observation balloons and Zeppelins.