An Atlas D LV-3B launching Mercury-Atlas 6 Expendable launch
system |Country of origin||United States| |Launch sites||LC-11,
12, 13 & 14, CCAFS |First flight||14 April 1959| |Last flight||7
November 1967| The SM-65D Atlas, or Atlas D, was the first
operational version of the U.S. Atlas missile. Atlas D missiles
were also used for orbital launches, both with upper stages and
on their own as a stage-and-a-half vehicle. The Atlas D testing
program began with the launch of Vehicle 3D from LC-13 on April
14, 1959. The right booster engine experienced problems at
ignition, falling to only 40% of full thrust. Additional
problems were caused when the LOX drain valve failed to close,
oxidizer spilled down the side of the booster and exploded on
contact with the engine exhaust. The vehicle lifted and
continued to fly at an oblique angle for about 20 seconds before
further explosions in the boattail section caused the right
booster engine to separate from the Atlas. With all control
lost, the burning missile pitched ove