. "4"^^ . "Retired" . . . . . "1958-07-19Z"^^ . "Atlas B (SM-65B)"@en . . "The SM-65B Atlas, or Atlas B, also designated X-12 was a prototype of the Atlas missile. First flown on 19 July 1958, the Atlas B was the first version of the Atlas rocket to use the stage and a half design.Ten flights were made. Nine of these were sub-orbital test flights of the Atlas as an Intercontinental Ballistic Missile, with five successful missions and four failures."@en . "6"^^ . "1959-02-04Z"^^ . "10"^^ . . .