T-00:02.7	Engine Start
The Russian-designed RD-180 main engine is ignited and undergoes checkout prior to launch.
T+00:01.1	Liftoff
The two strap-on solid rocket boosters are lit as the Atlas 5 vehicle, designated AV-016, lifts off and begins a vertical rise away from Complex 41 at Cape Canaveral Air Force Station, Florida.
T+02:19	Jettison SRBs
Having burned out of propellant approximately 50 seconds earlier, the spent solid rocket boosters are jettisoned to fall into the Atlantic Ocean.
T+04:15	Main Engine Cutoff
The RD-180 main engine completes its firing after consuming its kerosene and liquid oxygen fuel supply in the Atlas first stage.
T+04:21	Stage Separation
The Common Core Booster first stage of the Atlas 5 rocket 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+04:31	Centaur Ignition 1
The Centaur RL10 engine ignites for the longer of the two upper stage firings. This burn will inject the Centaur stage and WGS spacecraft into a parking orbit.
T+04:39	Nose Cone Jettison
The payload fairing that protected the WGS spacecraft during launch is separated once heating levels drop to predetermined limits.
T+15:14	Centaur Cutoff 1
The Centaur engine shuts down after arriving in a planned parking orbit. The vehicle enters a short coast period before arriving at the required location in space for the second burn.
T+24:20	Centaur Ignition 2
The Centaur re-ignites off the coast of Africa to accelerate the payload into geosynchronous transfer orbit from the parking achieved earlier in the launch sequence.
T+28:50	Centaur Cutoff 2
At the conclusion of its second firing, the Centaur will have delivered the WGS spacecraft into the targeted orbit with an apogee of 41,516 miles, perigee of 254 miles and inclination of 20.93 degrees.
T+31:39	Spacecraft Separation
The Air Force's second Wideband Global SATCOM spacecraft is released into orbit from the Centaur upper stage to complete the AV-016 launch.

Data source: United Launch Alliance.