T-00:02.4	Engine Start
	Atlas booster and sustainer engines are ignited and undergo checkout prior to liftoff.
T+00:00	Launch
	The two ground-lit solid rocket boosters are ignited as the Atlas 2AS vehicle, designated AC-167, lifts off and begins a vertical rise away from launch pad 36A at Cape Canaveral Air Force Station, Florida. The rocket will head northeast to reach a highly inclined orbit.
T+00:58.9	Air-lit SRB Ignition
	The remaining two solid rocket boosters strapped to the Atlas are ignited once onboard computer software determines the two ground-start SRBs have burned out, just seconds earlier.
T+01:17.0	Jettison Ground-Lit SRBs
	The two spent solid rocket boosters that were ignited on the ground are jettisoned to fall into the Atlantic Ocean.
T+01:56.0	Jettison Air-Lit SRBs
	Computer software will determine the air-start solid rocket boosters have burned all their propellant and should be jettisoned from the Atlas vehicle. The two SRBs will fall into the Atlantic Ocean.
T+02:44.0	Booster Engine Cutoff
	BECO occurs when axial acceleration of 5.0 g is obtained on the rocket. Sustainer engine provides the continued boost toward orbit for the Atlas rocket.
T+02:47.0	Jettison Booster Package
	The bottom engine structure with the two booster engine nozzles is separated from the Atlas vehicle.
T+03:28.1	Jettison Payload Fairing
	The 14-foot diameter aluminum payload fairing that protected the classified NRO spacecraft during launch is separated once heating levels drop to predetermined limits.
T+04:57.0	Sustainer Engine Cutoff
	SECO is commanded once minimum residual propellant is sensed inside the Atlas booster stage.
T+04:58.0	Atlas/Centaur Separation
	The Atlas booster stage separates from the Centaur upper stage. Over the next few seconds, the Centaur engine liquid hydrogen and liquid oxygen systems are readied for ignition.
T+05:15.0	Centaur Engine Start 1
	MES 1, the longer of the two Centaur firings begins to inject the upper stage and NRO spacecraft into a low-altitude parking orbit.
T+10:02.0	Centaur Engine Cutoff 1
	MECO 1 occurs the Centaur engines are shutdown, arriving in a planned parking orbit. The vehicle entered a lengthy coast period before arriving at the required location in space for the second burn.
T+68:35.0	Centaur Engine Start 2
	MES 2 occurs over the South Pacific to accelerate the payload into a dfferent orbit from the one achieved earlier in the launch sequence.
T+69:49.0	Centaur Engine Cutoff 2
	At MECO 2, the Centaur completes the powered flight to deliver the NRO spacecraft into the targeted deployment orbit. The parameters for that orbit are classified.
T+73:50.0	Spacecraft Separation
	The classified National Reconnaissance Office spacecraft is released into orbit from the Centaur upper stage to complete the AC-167 launch, the final flight for Lockheed Martin's Atlas 2AS rocket.

Image and data source: International Launch Services and Lockheed Martin Astronautics.