The ASU-57 was a small, lightly constructed Soviet assault gun specifically designed for use by Soviet airborne divisions. From 1960 onward, it was gradually phased out in favour of the ASU-85 and converted into armored command vehicles. The ASU-57 saw action in the Six Day War and Ogden War and was in service for countless countries. The ASU-57 was the first successful Soviet airborne tank design. In the 1930's, airborne divisions were first set-up and pioneered following the definition of the deep battle concept. Many air dropping solutions were tried with amphibious tanks, light tanks, and tankettes, but all failed at the end. In the 1950's, when the ASU-57 was introduced, all airborne divisions received 54 vehicles each. Early tests were performed under the Tu-4 bomber wings. However at the end of the 1950's, only 245 ASU-57 were in service, and the gun, derived of a 1943 design, was seen as obsolete.