Follow the Atlas 5 rocket’s ascent into orbit from Cape Canaveral’s Complex 41 launch pad with the U.S. Air Force’s GPS 2F-10 navigation satellite. Launch is scheduled for Wednesday at 11:36 a.m. EDT (1536 GMT).
T+0:00:01.1: Liftoff
The United Launch Alliance Atlas 5 vehicle, designated AV-055, will lift off and begin a vertical rise away from Complex 41 at Cape Canaveral Air Force Station, Florida.
T+0:01:18.5: Mach 1 and Max Q
The Atlas rocket achieves Mach 1 some 78 seconds into the flight, then passes through the region of maximum dynamic pressure at 90 seconds.
T+0:04:03.5: Main Engine Cutoff
The RD-180 main engine completes its firing after consuming the load of RP-1 kerosene fuel and liquid oxygen supply in the Atlas first stage.
T+0:04:09.5: 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+0:04:19.5: Centaur Ignition No. 1
The Centaur RL10 engine ignites for the longer of the two upper stage firings. This burn will inject the Centaur stage and GPS 2F-10 spacecraft into a transfer orbit.
T+0:04:27.5: Nose Cone Jettison
The two-piece, 14-foot-diameter payload fairing that protected the GPS 2F-10 craft during the atmospheric ascent is separated to reveal the satellite to space.
T+0:17:02.2: Centaur Engine Cutoff No. 1
The Centaur engine shuts down after arriving in a planned elliptical transfer orbit of 11,000 by 90 nautical miles. The vehicle enters a three-hour coast period before arriving at the required location in space for the second burn.
T+3:17:01:7: Centaur Ignition No. 2
The Centaur re-ignites to circularize the orbit and enter the Global Positioning System satellite constellation in delivery of GPS 2F-10.
T+3:18:28.5: Centaur Engine Cutoff No. 2
At the conclusion of its second firing, the Centaur will have delivered the GPS spacecraft into the targeted circular orbit of 11,047 nautical miles, inclined 55 degrees to the equator.
T+3:23:14.6: Spacecraft Separation
The Global Positioning System 2F-10 navigation satellite is released into orbit from the Centaur upper stage to complete the AV-055 launch.
See our earlier GPS 2F-10 coverage.
Our Atlas archive.