During and after World War II, over 4,500 Beech 18s were used in military service—as light transport, light bomber (for China), aircrew trainer (for bombing, navigation, and gunnery), photo-reconnaissance, and "mother ship" for target drones—including United States Army Air Forces (USAAF) C-45 Expeditor, AT-7 Navigator, and AT-11 Kansan; and United States Navy (USN) UC-45J Navigator, SNB-1 Kansan, and others. In World War II, over 90% of USAAF bombardiers and navigators trained in these aircraft.