| T-00:00 |
Liftoff |
| The Delta 2 rocket's main engine and twin vernier steering thrusters are started moments before launch. The four strap-on solid rocket motors are ignited at T-0 to begin the mission. |
|
| T+01:04.0 |
SRB Burnout |
| The ground-start Alliant TechSystems-built solid rocket motors consume all their propellant and burn out. |
|
| T+01:22.5 |
Jettison SRBs |
| 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+01:25.0 |
Begin Dog-leg |
| After initially flying from Vandenberg along a 196-degree flight azimuth, the rocket begins steering itself to obtain the desired orbital inclination. This dog-leg maneuver continues for 35 seconds. |
|
| T+04:24.0 |
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+04:32.0 |
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+04:37.5 |
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 COSMO 4 spacecraft into the proper orbit. |
|
| T+04:41.5 |
Jettison Payload Fairing |
| The 10-foot diameter payload fairing that protected the COSMO 4 cargo atop the Delta 2 during the atmospheric ascent is jettisoned is two halves. |
|
| T+11:25.1 |
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 348 nautical miles at apogee, 100 miles at perigee and inclined 97.8 degrees. |
|
| T+53:27.0 |
Second Stage Restart |
| Delta's second stage engine reignites for a short firing to raise the orbit's perigee. |
|
| T+53:39.4 |
Second Stage Cutoff 2 |
| The second stage shuts down after a 12-second burn. The orbit achieved should be 341.0 nautical miles at apogee, 334.7 miles at perigee and inclined 97.86 degrees. |
|
|
| T+58:00.0 |
Payload Separation |
| The Italian COSMO-SkyMed radar Earth-imaging satellite is released from the Delta 2 rocket, completing the launch. |
