4:22 p.m. Cygnus begins transfer to internal power
4:29 p.m. Cygnus verified configured for launch
4:37 p.m. Status check to continue countdown
4:44:54 p.m. T-4 Minutes and counting
4:44:54 p.m. RD-180 engine ignition
4:44:57 p.m. Launch
4:45:15 p.m. Begin pitch/yaw/roll maneuver
4:46:19 p.m. Mach 1
4:46:30 p.m. Maximum Dynamic Pressure
4:49:12 p.m. Atlas booster engine cutoff (BECO)
4:49:18 p.m. Atlas booster/Centaur separation
4:49:28 p.m. Centaur first main engine start (MES1)
4:49:36 p.m. Payload Fairing jettison
5:03:13 p.m. Centaur first main engine cutoff (MECO1)
5:06:02 p.m. Cygnus spacecraft separation
~5:45 p.m. Cygnus solar array deploy