T-00:00:03	Engines at Full Thrust
The five main engines of the Soyuz rocket's core stage and four strap-on boosters are at full thrust.
T-00:00:00	Launch
Producing more than 900,000 pounds of thrust, the Soyuz 2-1a rocket soars into the sky from the Guiana Space Center.
T+00:01:58	Jettison Boosters
The Soyuz rocket's four strap-on boosters, each powered by an RD-107A engine, are jettisoned after consuming their propellant.
T+00:03:29	Jettison Fairing
The ST-type payload fairing is released from the Soyuz rocket when it reaches the edge of the upper atmosphere. The 13.5-foot-diameter fairing protects the payload during the launch countdown and the flight through the dense lower atmosphere.
T+00:04:47	Core Stage Separation
Having burned its propellant, the core stage of the Soyuz rocket, also known as the second stage, separates and the third stage's RD-0110 engine ignites to continue the flight.
T+00:08:47	Soyuz/Fregat Separation
The Soyuz rocket's third stage releases the Fregat upper stage just shy of orbital velocity.
T+00:09:47	First Fregat Ignition
The hydrazine-fueled Fregat upper stage ignites to place the Pleiades 1B satellite in a low-altitude parking orbit.
T+00:13:26	First Fregat Shutdown
The Fregat upper stage shuts down to begin a coast phase.
T+00:41:56	Second Fregat Ignition
The Fregat stage's main engine fires for a second time to circularize its orbit at an altitude of 432 miles above Earth.
T+00:46:05	Second Fregat Shutdown
After a 4-minute, 9-second burn, the Fregat upper stage shuts down after entering a circular orbit with an inclination of 98.2 degrees.
T+00:54:55	Pleiades 1B Separation
The Pleiades 1B satellite separates from the upper position on the Soyuz rocket's Fregat upper stage.

Data source: Arianespace