| L-11:43:00 |
Countdown Initiation |
| L-10:23:00 |
Ariane 5 Power-Up |
| L-09:30:00 |
Electrical Systems Checks |
| L-07:30:00 |
Vehicle in Fueling Configuration |
| L-06:00:00 |
Launch Pad Close-Outs |
| L-06:00:00 |
Flight Software Load |
| L-06:00:00 |
Communication Checks |
| L-06:00:00 |
Inertial Guidance System Alignment |
| L-05:00:00 |
Launch Pad Evacuation |
| L-05:00:00 |
Attitude Control System Pressurization |
| L-04:50:00 |
Propellant Loading Ops |
| L-04:50:00 |
GSE LOX and LH2 Tank Pressurization |
| L-04:30:00 |
Propellant Transfer Lines Chilldown |
| L-04:23:00 |
First Stage Propellant Loading |
| L-03:43:00 |
Second Stage Propellant Loading |
| L-03:33:00 |
Vulcain Main Engine Chilldown |
| L-02:00:00 |
Propellant Topping Sequence |
| L-01:15:00 |
Telemetry, Tracking, Command Systems Checkouts |
| L-00:30:00 |
Prepare for Synchronized Sequence |
| L-00:10:00 |
GO/No GO for Launch |
| L-00:08:00 |
Payloads to internal Power |
| L-00:07:00 |
Countdown Hold&Recycle Point |
| T-00:07:00 |
SYNCHRONIZED SEQUENCE |
| T-00:06:30 |
Propellant Topping Termination |
| T-00:06:30 |
LOX & LH2 at Flight Level |
| T-00:06:30 |
Launch pad safety flood valves opened |
| T-00:06:30 |
Pyrotechnic Safety Barrier Arming |
| T-00:06:00 |
Launcher Ordnances armed |
| T-00:06:00 |
First Stage Helium Loading Termination |
| T-00:04:00 |
First Stage Propellant Tank Pressurization |
| T-00:04:00 |
Propellant GSE Interface Purge |
| T-00:04:00 |
Second Stage LOX Load Termination |
| T-00:04:00 |
Second Stage LOX Pressurization |
| T-00:03:40 |
Second Stage LH2 Load Termination |
| T-00:03:30 |
Launch Time Calculation |
| T-00:03:10 |
Second Stage LH2 Pressurization |
| T-00:03:00 |
Final T0 loaded into Onboard Computers |
| T-00:02:30 |
First Stage, VEB Battery Heating Termination |
| T-00:02:30 |
Vulcain Ignition System Heater Shutdown |
| T-00:02:00 |
Vulcain 2 Bleeder Valves Open |
| T-00:02:00 |
Chilldown Valves closed |
| T-00:01:50 |
Pre-Deflection of HM-7B Engine |
| T-00:01:05 |
Transition to internal Power |
| T-00:01:05 |
Second Stage Isolation from GSE, Tightness Check |
| T-00:00:37 |
Ignition Sequence Start |
| T-00:00:37 |
On-Board Recorder Activation |
| T-00:00:37 |
Arming of pyrotechnic line electric safety barriers |
| T-00:00:30 |
Verification of Propellant System Purge |
| T-00:00:30 |
First Stage Flood Valves Open |
| T-00:00:22 |
First Stage Attitude Control System enabled |
| T-00:00:16.5 |
POGO Pressurization |
| T-00:00:16.5 |
Fairing Ventilation Termination |
| T-00:00:12 |
Flood Valves Opening Command |
| T-00:00:06 |
Cryogenic Umbilicals Retraction |
| T-00:00:06 |
Start Hydrogen Burn Off System |
| T-00:00:05.5 |
Transfer to On-Board Control |
| T-00:00:03 |
Guidance System Transition to Flight Mode |
| T-00:00:03 |
Computer Status Check |
| T-00:00:03 |
Helium Pressurization System Active |
| T-00:00:02.5 |
Verification of HM-7B Nozzle Deflection |
| T-00:00:02 |
Launch Pad Water System Activation |
| T-00:00:01.4 |
Engine Purge Valve Closed |
| T-00:00:00.2 |
Arm Retraction Confirmation |
| T-00:00:00 |
Vulcain 2 Main Engine Ignition |
| T+00:00:06.90 |
End of Vulcain Checkout |
| T+00:00:07.05 |
Solid Rocket Booster Ignition |
| T+00:00:07.30 |
LIFTOFF |
