Soyuz launch countdown timeline
The Soyuz TMA-15 spacecraft, transporting ESA astronaut Frank De Winne, Russian cosmonaut Roman Romanenko and Canadian Space Agency astronaut Robert Thirsk to the International Space Station, was carried into orbit by a Soyuz FG launcher from Baikonur Cosmodrome in Kazakhstan.
The main events during the countdown to launch at 12:34 CEST on 27 May are as follows.
| Time to launch | Chronology of events |
| -06h00 | Start of final countdown launcher and Soyuz |
| -04h20 | Crew dons spacesuit |
| -03h00 |
Start filling hydrogen peroxide, liquid nitrogen, kerosene and liquid oxygen tanks. Soyuz capsule - venting of shrouds |
| -02h45 | Authorisation from flight commission |
| -02h40 |
End of filling. Start of purge operations. Crew arrives at launch pad |
| -02h30 | Crew enters Soyuz capsule |
| -02h20 |
Electronic systems switch on Topping up of fuels Crew checks radio links |
| -01h55 |
Hatch closure Check of Soyuz reentry capsule |
| -01h40 | End of check of Soyuz reentry capsule |
| -01h30 | Check of Soyuz onboard equipment |
| -01h20 |
Measurement of system status Pressure and temperature check On-board engineer checks air-tightness of the reentry module End of crew commands |
| -01h10 |
Switch on of third stage inertial guidance systems Switch on of communication systems |
| -01h00 |
Triggering of inertial guidance systems Evacuation of launcher teams |
| -45m |
Loading of flight instructions (flight programme) starts Rollback of service gantries |
| -40m | Check of spacesuit air-tightness |
| -30m |
Switch on of safety systems End of on board commands |
| -25m | Loading of flight instructions (flight programme) end |
| -15m |
Launch site total evacuation Unlocking of inertial guidance systems |
| -11m | Automated ignition sequence ready in 5 min |
| -6m | Automatic sequence: ready for ignition |
| -5m | Activation ground and on board telemetry |
| -2m40s | Third stage switches to internal power |
| -29s | Ignition of engines |
| H0 | Liftoff |