Redstone Army Airfield or Redstone AAF (IATA: HUA, ICAO: KHUA, FAA LID: HUA) is a military airport located at Redstone Arsenal, six miles (10 km) southwest of the city of Huntsville in Madison County, Alabama, USA. The Airfield was originally constructed for munitions testing through the 6th AAF Base Unit (Proving Ground Detachment). It is currently used to support the U.S. Army Aviation and Missile Command, NASA, and the Flying Activity.