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Soyuz countdown timeline
Posted: October 11, 2012

T-04:20:00 Russian State Commission Meets
The Russian State Commission meets to authorize fueling of the Soyuz rocket.
T-04:00:00 Fueling Begins
Loading of kerosene and liquid oxygen propellants begins for the Soyuz rocket's three lower stages.
T-01:45:00 Fueling Complete
The rocket is fully fueled for launch.
T-01:00:00 Gantry Retracts
The 170-foot-tall mobile service gantry moves to the launch position on rails, revealing the Soyuz rocket for launch.
T-00:06:10 Key on Start
The launch key is put in place in the control center to begin the Soyuz synchronized countdown sequence.
T-00:05:00 Fregat on Internal Power
The Fregat-MT upper stage is tranferred to internal battery power.
T-00:02:25 Upper Umbilical Retracts
The umbilical arm reaching the upper portion of the Soyuz rocket retracts.
T-00:00:40 Soyuz on Internal Power
The Soyuz rocket transitions to internal power.
T-00:00:20 Lower Umbilical Retracts
The umbilical arm servicing the lower portion of the Soyuz rocket retracts.
T-00:00:17 Ignition
The ignition sequence begins for the Soyuz rocket's core stage and four strap-on boosters.
T-00:00:03 Full Thrust
The RD-107A and RD-108A engines reach their full power level, totaling more than 900,000 pounds of thrust.
T-00:00:00 Liftoff
The launch pad hold-down arms retract and the Soyuz rocket soars into the sky.

Data source: Arianespace