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Minotaur launch timeline
Posted: September 26, 2011

T-00:00 Liftoff
The first stage's decommissioned Peacekeeper SR118 solid rocket motor ignites to begin the Minotaur 4 rocket's mission. Pitch and roll commands two seconds later will put the rocket on the proper trajectory.
T+00:37 Max Q
Aerodynamic pressure on the vehicle reaches its peak as the Minotaur 4 accelerates through the lower atmosphere.
T+00:57 Stage 1 Sep./Stage 2 Ignition
At an altitude of 15 miles, the rocket's ATK-built solid-fueled first stage exhausts its supply of propellant and is jettisoned. The second stage's SR119 motor ignites to continue the flight toward space.
T+01:55 Stage 2 Burnout
The second stage SR119 motor, built by Aerojet, burns out at an altitude of 58 miles.
T+02:05 Stage 2 Sep./Stage 3 Ignition
After a 10-second coast, the Hercules SR120 third stage motor fires for a 72-second burn.
T+02:17 Fairing Jettison
The 92-inch graphite-epoxy aluminum honeycomb payload fairing that protected the satellites during the ride through the lower atmosphere is jettisoned as the rocket ascends into space at an altitude of 78 miles.
T+03:18 Stage 3 Burnout
The Hercules SR120 motor completes its burn and the Minotaur 4 enters a coast period lasting almost 20 minutes, during which the vehicle's altitude will soar to more than 400 miles.
T+22:55 Stage 3 Separation
The Minotaur's third stage is released to re-enter Earth's atmosphere.
T+23:06 Stage 4 Ignition
The Star 48 solid rocket motor is ignited to complete the job of placing the payload into orbit. This is the first flight of a Minotaur 4 rocket with the Star 48 fourth stage motor. This version of the rocket is called the Minotaur 4+ configuration.
T+24:28 Stage 4 Burnout
The fourth stage uses up its propellant and burns out as it enters the targeted elliptical orbit with a perigee altitude of about 115 miles, an apogee altitude of 7,487 miles, and an orbital inclination of 63.435 degrees.
T+27:48 TacSat 4 Separation
The Navy's TacSat 4 satellite is deployed from the Minotaur 4 rocket's fourth stage.

Data source: Orbital Sciences Corp.