The SM-65 Atlas was the first operational intercontinental ballistic missile (ICBM) developed by the United States and the first member of the Atlas rocket family. It was built for the U.S. Air Force by the Convair Division of General Dynamics at an assembly plant located in Kearny Mesa, San Diego.
Development dates to 1946, but over the next few years the project underwent several cancellations and re-starts. The deepening of the Cold War and intelligence showing the Soviet Union was working on an ICBM design led to it becoming a crash project in late 1952, along with the creation of several other missile projects to ensure one would enter service as soon as possible. The first test launch was carried out in June 1957, which failed. The first success of the Soviet R-7 Semyorka in August gave the program new urgency, leading to the first successful Atlas A launch in December. Of the eight flights of the A model, only three were successful, but the later models demonstrated increasing reliability and the C model was cleared for use.
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