Which booster was used to send the 1st American into orbit?
Orion abort modes:  Based on the launch escape system found on the Soviet/Russian Soyuz spacecraft, the LAS, designed and manufactured by ATK for the Orion CEV, will be larger than the Soyuz version and will have more thrust than the Atlas 109-D booster that carried astronaut John Glenn into orbit in 1962. John Glenn:  In 1962 he became the first American to orbit the Earth, circling it three times.
Atlas 109-D booster