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Delta 322 launch timeline
Posted: December 12, 2006

T-00:00 Liftoff
The Delta 2 rocket's main engine and twin vernier steering thrusters are started moments before launch. The six ground-start strap-on solid rocket motors are ignited at T-0 to begin the mission.
T+01:04.0 Ground SRM Burnout
The ground-start Alliant TechSystems-built solid rocket motors consume all their propellant and burn out.
T+01:05.5 Air-Lit SRM Ignition
The three remaining solid rocket motors strapped to the Delta 2 rocket's first stage are ignited.
T+01:26.0 Jettison Ground SRMs
The spent solid rocket boosters are jettisoned to fall into the Pacific Ocean. The spent casings remained attached until the vehicle passed into preset drop zone, clear of offshore oil platforms.
T+01:30.0 Begin Dog-leg
After initially flying from Vandenberg along a 196-degree flight azimuth, the rocket begins steering itself in a more southeastward direction to obtain the desired orbital inclination. This dog-leg maneuver continues until T+plus 2 minutes, 22 seconds.
T+02:11.5 Jettison Air-Lit SRMs
Having burned out two seconds earlier, the three spent air-started solid rocket boosters are jettisoned.
T+04:23.4 Main Engine Cutoff
After consuming its RP-1 fuel and liquid oxygen, the Pratt & Whitney Rocketdyne RS-27A first stage main engine is shut down. The vernier engines cut off moments later.
T+04:31.4 Stage Separation
The Delta rocket's first stage is separated now, having completed its job. The spent stage will fall into the Pacific Ocean.
T+04:36.9 Second Stage Ignition
With the stage jettisoned, the rocket's second stage takes over. The Aerojet AJ118-K liquid-fueled engine ignites for the first of two firings needed to place the NRO spacecraft into the proper orbit.
T+04:41.0 Jettison Payload Fairing
The 10-foot diameter payload fairing that protected the NRO cargo atop the Delta 2 during the atmospheric ascent is jettisoned is two halves.
T+10:58.2 Second Stage Cutoff 1
The second stage engine shuts down to complete its first firing of the launch. The rocket and attached spacecraft are now in a long coast period before the second stage reignites. The orbit achieved should be 202 nautical miles at apogee, 100 miles at perigee and inclined 58.6 degrees.
T+55:13.2 Second Stage Restart
Delta's second stage engine reignites for a short firing to raise the orbit's perigee.
T+55:18.7 Second Stage Cutoff 2
The second stage shuts down after a five-second burn. The orbit achieved should be 203 nautical miles at apogee, 191 miles at perigee and inclined 58.5 degrees.
T+57:50.0 Payload Separation
The classified payload for the U.S. National Reconnaissance Office is released from the Delta 2 rocket, completing the first United Launch Alliance space mission.

Data source: ULA.