| T-00:02.7 | Engine Start | 
	
		
| The Russian-designed RD-180 main engine is ignited and undergoes checkout prior to launch. | 
	
		
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| T+00:01.1 | Liftoff | 
	
		
| The three strap-on solid rocket boosters are lit as the Atlas 5 vehicle, designated AV-041, lifts off and begins a vertical rise away from Complex 41 at Cape Canaveral Air Force Station, Florida. | 
	
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T+00:05.4 | Begin Pitch/Roll/Yaw Maneuver | 
		
| The 196-foot-tall Atlas 5 begins to maneuver itself on the proper trajectory east of Complex 41 on an azimuth of 90.13 degrees. | 
	
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T+00:38.2 | Mach 1 | 
		
| Burning its RD-180 main engine and three solid rocket boosters, the Atlas 5 rocket passes the speed of sound. | 
	
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T+00:46.7 | Max-Q | 
		
| The Atlas 5 rocket passes the region of flight known as maximum dynamic pressure, or Max-Q. | 
	
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| T+01:56 | Jettison SRBs | 
	
| Having burned out of propellant approximately 25 seconds earlier, the spent solid rocket boosters are jettisoned to fall into the Atlantic Ocean. | 
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| T+03:29 | Nose Cone Jettison | 
	
		
| The payload fairing that protected the AEHF 3 spacecraft during launch is separated once heating levels drop to predetermined limits. | 
	
		
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| T+03:34 | Forward Load Reactor Jettison | 
	
		
| The Forward Load Reactor deck that supported the payload fairing's structure to Centaur upper stage is released seconds after the shroud's jettison. | 
	
		
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| T+04:17 | 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. | 
	
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| T+04:23 | 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. | 
	
		
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| T+04:33 | 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 AEHF 3 spacecraft into a parking orbit. | 
	
	
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| T+14:00 | Centaur Cutoff 1 | 
	
| The Centaur engine shuts down after arriving in a planned parking orbit. The vehicle enters a brief coast period lasting nearly 8 minutes before arriving at the required location in space for the second burn. | 
	
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| T+21:57 | Centaur Ignition 2 | 
	
| The Centaur re-ignites over the equatorial Atlantic to accelerate the payload into supersynchronous transfer orbit from the parking achieved earlier in the launch sequence. | 
	
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| T+27:35 | Centaur Cutoff 2 | 
	
| At the conclusion of its second firing, the Centaur will have delivered the AEHF 3 spacecraft into the targeted orbit with an apogee of 31,069 statute miles, perigee of 140 statute miles and inclination of 20.9 degrees. | 
	
| T+50:58 | Spacecraft Separation | 
	
		
| The U.S. military's fourth Advanced Extremely High Frequency communications satellite is released into orbit from the Centaur upper stage to complete the AV-041 launch. |