#ThrowbackThursday SM-65 Atlas... The Atlas became operational in 1959. Because of the vulnerability of the Atlas while above ground, an underground silo was developed. An elevator raised it to ground-level for launching. While on alert duty, the Atlas missile was maintained in the fully raised (above ground) position since it could not be launched from its underground silo. The silo was only for protection from enemy attack. The Atlas ICBM could deliver a nuclear warhead more than 6,300 miles f