Fairfax Field was a wartime (WWII) facility of the United States Army Air Forces and later, the United States Air Force. The installation was north of Kansas City, Kansas. Used as a pre-war Naval Air Station, the United States Army Air Forces leased the municipal airfield and built an and modification center for North American B-25 Mitchell medium bomber production. Military use of the site continued as late as 1957 by the Strategic Air Command's 3903rd Radar Bomb Scoring Group for bombing practice. Kansas City military sites in Missouri