1960-05-20 USA Atlas-D Launch

An Atlas 56D record-range ICBM launch cover from "Goldcraft", postmarked at Cape Canaveral with a hand cancel on May 20, 1960.

Atlas 56D was an Air Force research-and-development flight of the SM-65D Atlas ICBM, launched from Launch Complex 12 at Cape Canaveral at approximately 11:00 a.m. EST on May 20, 1960. The flight was successful and became notable for its extraordinary range.

The missile carried a Mark 3 Mod IB reentry vehicle and a simulated warhead payload. Rather than placing a satellite into orbit, the mission was intended to demonstrate the Atlas's ability to deliver a payload over intercontinental distances. Atlas 56D flew approximately 9,040 statute miles (7,859 nautical miles) before impacting in the Indian Ocean southwest of Cape Town, South Africa. At the time, this was the longest U.S. missile flight on record.

The flight was also significant because it was the first Atlas launch from LC-12 following the major damage caused by the Atlas 9C explosion in September 1959. The launch incorporated modifications to the facilities, including cameras positioned to observe the missile's engine area during liftoff.

(Reference from Cape Canaveral Launch Complex 12)