Two orbits. Five satellites. Four upper stage burns. Follow the key events scheduled during the European Vega rocket’s launch from French Guiana with the PeruSat 1 high-resolution reconnaissance satellite and four commercial eyes-in-the-sky owned by Google’s Terra Bella imaging company.
T+00:00:00 — Liftoff
The Vega rocket’s first stage P80 solid rocket motor ignites and powers the 98-foot-tall booster off the launch pad 0.3 seconds later. The P80 first stage motor generates a maximum of 683,000 pounds of thrust.
T+00:00:31 — Mach 1
The Vega rocket surpasses the speed of sound as it soars on an easterly trajectory from French Guiana. The rocket will reach Max-Q, the point of maximum aerodynamic pressure, at T+plus 53 seconds.
T+00:01:54 — First stage separation
Having consumed its 194,000 pounds (88 metric tons) of solid propellant, the 9.8-foot-diameter (3-meter) P80 first stage motor is jettisoned at an altitude of about 33 miles (53 kilometers). The second stage Zefiro 23 motor will ignite a second later to begin its 103-second firing.
T+00:03:38 — Second stage separation
The Zefiro 23 motor burns out and jettisons.
T+00:03:59 — Third stage ignition
Moving at a velocity of nearly 9,000 mph, or about 3.9 kilometers per second, the Vega rocket’s Zefiro 9 motor ignites for the third stage burn.
T+00:04:04 — Fairing separation
The Vega’s 8.5-foot-diameter (2.6-meter) payload fairing is released as the rocket ascends into space.
T+00:06:41 — Third stage separation
The Zefiro 9 third stage shuts down and separates, having accelerated the rocket to nearly orbital velocity.
T+00:08:07 — First AVUM ignition
The Vega rocket’s Attitude and Vernier Module, or fourth stage, ignites for the first time. The AVUM burns hydrazine fuel with an RD-843 engine provided by Yuzhnoye of Ukraine.
T+00:14:10 — AVUM first cutoff
The Vega’s AVUM fourth stage is turned off after an 6-minute, 3-second burn, beginning a 24-minute coast until the engine is ignited again.
T+00:38:05 — Second AVUM ignition
The AVUM fires a second time for a 89-second burn to put the four SkySat satellites into their targeted orbit.
T+00:39:34 — AVUM second cutoff
The AVUM engine shuts down after reaching a near circular orbit with a high point of 315 miles (508 kilometers), a low point of 305 miles (491 kilometers), and an inclination of 97.4 degrees.
T+00:40:21 — SkySat 4-7 separation
The four SkySat Earth observation satellites mounted in the upper position on the Vega rocket’s Vespa dual-payload adapter separate one by one starting at T+plus 40 minutes, 21 seconds, and ending seven seconds later.
T+00:54:44 — Third AVUM ignition
After jettisoning a cover to expose the PeruSat 1 satellite, the AVUM’s RD-843 engine fires a third time for a 47-second burn to boost into a higher orbit for deployment of PeruSat 1.
T+00:55:31 — AVUM third cutoff
The AVUM fourth stage shuts down to begin a 46-minute coast phase before its next burn.
T+01:41:20 — Fourth AVUM ignition
The AVUM main engine ignites a fourth time for a 45-second burn.
T+01:42:05 — AVUM fourth cutoff
The RD-843 engine shuts down after reaching an orbit with a low point of 414 miles (667 kilometers), a high point of 425 miles (684 kilometers), and an inclination of 98.2 degrees.
T+01:42:59 — PeruSat 1 separation
The 948-pound (430-kilogram) PeruSat 1 satellite separates from the Vega rocket’s fourth stage. The upper stage’s RD-843 engine will ignite again a few minutes later to head for a disposal orbit.
Email the author.
Follow Stephen Clark on Twitter: @StephenClark1.
from Spaceflight Now