NASA
Scott Carpenter was the sixth human and the fourth American in space.
May 24, 1962. 7:45:16 EST. The launch countdown proceeded almost perfectly, with only a last-minute hold of 45 minutes occurring at the T-11 minutes mark in anticipation of better camera coverage and to allow aircraft to check the atmospheric refraction index in the vicinity of Cape Canaveral. The launch vehicle used to accelerate Scott Carpenter and the Aurora 7 spacecraft was an Atlas D.
Total time weightless 4 hours 39min 32sec. The performance of the Mercury spacecraft and Atlas launch vehicle was excellent in nearly every respect. All primary mission objectives were achieved. The single mission critical malfunction which occurred involved a failure in the spacecraft pitch horizon scanner, a component of the automatic control system. This anomaly was adequately compensated for by the pilot in subsequent in-flight operations so that the success of the mission was not compromised.