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Atlas/MUOS 1 launch timeline
Posted: February 9, 2012

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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 five strap-on solid rocket boosters are lit as the Atlas 5 vehicle, designated AV-030 lifts off and begins a vertical rise away from Complex 41 at Cape Canaveral Air Force Station, Florida.
T+01:44.6 Jettison SRBs
Having burned out of propellant approximately 15 seconds earlier, the spent solid rocket boosters are jettisoned to fall into the Atlantic Ocean. The separation event is staggered with two motors releasing first, then the others about 1.5 seconds later.
T+03:22.2 Nose Cone Jettison
The payload fairing that protected the MUOS 1 spacecraft during launch is separated once heating levels drop to predetermined limits after passage through the atmosphere.
T+03:27.2 Forward Load Reactor Jettison
The Forward Load Reactor deck that supported the payload fairing's structure to Centaur upper stage is released five seconds after the shroud's jettison.
T+04:24.1 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+04:30.1 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+04:40.1 Centaur Ignition 1
The Centaur RL10 engine ignites for the first of three upper stage firings. This burn will inject the Centaur stage and MUOS spacecraft into an initial parking orbit.
T+12:21.0 Centaur Cutoff 1
The Centaur engine shuts down after arriving in a planned low-Earth parking orbit of 90 by 337 nautical miles at 28 degrees inclination. The vehicle enters an 8-minute coast period before arriving at the required location in space for the second burn.
T+20:48.9 Centaur Ignition 2
The Centaur re-ignites to accelerate the payload into a highly elliptical transfer orbit from the parking altitude achieved earlier in the launch sequence.
T+26:50.1 Centaur Cutoff 2
At the conclusion of its second firing, the Centaur will have ascending into a 104 by 18,600 nautical mile orbit inclined 26 degrees to begin a two-and-a-half-hour coast.
T+2:56:50.4 Centaur Ignition 3
A final push by Centaur is ignited to raise the orbit's low point and reduce orbital inclination for the MUOS spacecraft.
T+2:57:44.2 Centaur Cutoff 3
The powered phase of flight is concluded as the Centaur, making its 200th launch, reaches the planned geosynchronous transfer orbit of 1,870 by 19,323 nautical miles and 19 degrees inclination.
T+3:01:23.2 Spacecraft Separation
The U.S. Navy's first Mobile User Objective System spacecraft, MUOS 1, is released into orbit from the Centaur upper stage to complete the AV-030 launch.

Data source: United Launch Alliance.