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+00:04:48	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+00:08:46	Soyuz/Fregat Separation
The Soyuz rocket's third stage releases the Fregat upper stage just shy of orbital velocity.
T+00:09:46	First Fregat Ignition
The hydrazine-fueled Fregat upper stage ignites to place the Sentinel 1A spacecraft into orbit.
T+00:20:04	First Fregat Shutdown
The Fregat upper stage shuts down after placing Sentinel 1A in a 693-kilometer (430-mile) orbit with an inclination of 98.2 degrees.
T+00:23:24	Sentinel 1A Separation
The Fregat upper stage releases the 2,157-kilogram (4,755-pound) Sentinel 1A spacecraft in orbit.
T+00:25:34	Sentinel 1A AOS
The first communications signals from Sentinel 1A are received through the Svalbard ground station in Norway, confirming the satellite's status after launch.
T+00:59:15	Second Fregat Ignition
The Fregat upper stage ignites to de-orbit the rocket to comply with space debris guidelines.
T+01:00:36	Second Fregat Shutdown
The Fregat upper stage completes its de-orbit burn to fall into a remote part of the ocean.

Data source: Arianespace