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-12 navigation satellite. Launch is scheduled for Friday at 8:38 a.m. EST (1338 GMT).
T+0:04:10: 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+0:04:20: 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-12 spacecraft into a transfer orbit.
T+0:17:04: 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+3:18:30: 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.
See earlier GPS 2F-12 coverage.
Our Atlas archive.