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Swift launch timeline
Posted: November 11, 2004

T-00:00 Liftoff
The Delta 2 rocket's main engine and twin vernier steering thrusters are started moments before launch. The three ground-start strap-on solid rocket motors are ignited at T-0 to begin the mission.
T+01:03.1 Ground SRM Burnout
The three ground-start Alliant TechSystems-built solid rocket motors consume all their propellant and burn out. The Delta 2 continues its trek to space on the thrust generated by the first stage main engine.
T+01:06.0 Jettison Ground SRMs
The spent solid rocket boosters are jettisoned to fall into the Atlantic Ocean. The light weight of Swift and orbit requirements means this mission uses just three solid boosters instead of the usual nine for Delta 2 launches.
T+04:24.3 Main Engine Cutoff
After consuming its RP-1 fuel and liquid oxygen, the Rocketdyne RS-27A first stage main engine is shut down. The vernier engines cut off moments later.
T+04:32.3 Stage Separation
The Delta rocket's first stage is separated now, having completed its job. The spent stage will fall into the Atlantic Ocean.
T+04:37.8 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 three firings needed to place Swift into the proper orbit.
T+04:57.5 Jettison Payload Fairing
The 10-foot diameter composite payload fairing that protected the Swift satellite atop the Delta 2 during the atmospheric ascent is jettisoned is two halves.
T+10:16.0 Second Stage Cutoff 1
The second stage engine shuts down to complete its first firing of the launch. The rocket and attached Swift spacecraft are now in a coast period before the second stage reignites. The orbit achieved should be circular at 100 nautical miles and inclined 28.47 degrees.
T+26:11.0 Second Stage Restart
Delta's second stage engine reignites for a short firing to raise the orbit's high point and lower the inclination.
T+26:40.8 Second Stage Cutoff 2
The second stage shuts down after a half-minute firing. The orbit achieved should be 334 nautical miles at apogee, 98 miles at perigee and inclined 26 degrees. The vehicle enters an extended coast period.
T+71:17.0 Second Stage Restart
Delta's second stage engine reignites again to propel Swift into its desired low-Earth orbit.
T+72:11.2 Second Stage Cutoff 2
The second stage shuts down to complete the powered phase of Swift's launch. The orbit achieved should be circular at 324 nautical miles (373 statute miles) and inclined at 22 degrees or less.
T+80:00.0 Swift Separation
NASA's Swift gamma-ray burst observatory is released into space. Separation bolts between the second stage and spacecraft are fired at T+plus 79:30. The latches are opened at T+plus 80 minutes to deploy the spacecraft. The second stage uses its helium system to gently back away from the satellite over the next 42 seconds. The spent stage performs an evasive maneuver and fuel depletion engine firing later.

Data source: Boeing.