Detailed Countdown Timeline

All times a.m. EST.  11/26
T- L- Event EDT
  12:00 Verfiy Countdown Clock is in proper Configuration 10:02PM
    Countdown Begins  
    MLP Clear of non essential personnel  
    Launch Pad Environmental Control System Preps  
    Nitrogen Purge  
    Weather Briefing  
    Search Light Power Up  
    SLC41 warning lights on  
  08:30 MLP to Launch Pad 1:32:00
    MLP Hard Down and Securing  
    Atlas System Start in preparation for Tanking  
    Instrument Checks  
    Lox System Preparations  
    Gas Detection System Preparations  
    Internal Battery Checks  
    LH2 System Preparations  
  07:05 Set Roadblocks 2:57:00
  07:00 A/C Power on 3:02:00
  05:25 Weather Briefing 4:37:00
  05:00 Communication Checks 5:02:00
  05:00 C-Band Communication Checks 5:02:00
  04:50 Weather Balloon Release 5:12:00
  04:20 S-Band Communication Checks 5:42:00
  04:00 L-4HR Commanding 6:02:00
  04:00 Polls 6:02:00
  03:35 Initiation of Nitrogen Flow 6:27:00
  03:34 Set Spacecraft Clock 6:28:00
  03:00 SLC Clear of all Personnel 7:02:00
02:00 02:40 Launch Conducter Briefing on Vehicle Conditions 7:22:00
HOLDING   GO/No GO for Tanking Poll  
30min Hold   Pre-Test Tanking Briefing  
02:00 02:10 Centaur LOX Tank Chilldown 7:52:00
COUNTING 02:10 Atlas LOX Vault & MLP Chilldown 7:52:00
  02:10 Centaur Helium Storage Bottle Pressurization 7:52:00
  02:10 Atlas Pressure Vessels Charge 7:52:00
  02:10 Atlas V RP-1 Fuel Tank Press 7:52:00
01:55 02:05 Safe Arm Device Cycle Test 7:57:00
01:50 02:00 Centaur LOX Transfer Line Chilldown 8:02:00
01:43 01:53 Centaur LOX Tanking begins 8:09:00
01:40 01:50 Weather Balloon Release 8:12:00
01:33 01:43 Centaur LH2 Tank Press to Chilldown Level 8:19:00
01:30 01:40 Atlas V LOX Tanking begins 8:22:00
01:25 01:35 Centaur LOX at 75% 8:27:00
01:25 01:35 Centaur LH2 Transfer Lines Chilldown 8:27:00
01:20 01:30 Centaur LH2 Loading 8:32:00
01:00 01:10 Centaur Engine Chilldown 8:52:00
00:55 01:05 Flight Control Final Preparations for Hydraulic Press 8:57:00
00:45 00:55 Main Engine Pneumatic System Press to Flight Level 9:07:00
00:40 00:50 Heater Activation 9:12:00
00:40 00:50 FTS Test 9:12:00
00:35 00:45 FGM Activation 9:17:00
00:25 00:35 Load Boost Block 9:27:00
00:20 00:30 Fault Protection Validation 9:32:00
00:17 00:27 Polls for Terminal Countdown 9:35:00
00:16 00:26 Fuel Fill Sequence Initiation 9:36:00
00:15 00:25 History Data Dump 9:37:00
00:15 00:25 Term CT Configuration complete 9:37:00
00:11 00:21 Range Clear for Launch 9:41:00
00:10 00:20 Weather Briefing 9:42:00
00:07 00:17 Range Clear Poll 9:45:00
00:06 00:16 Spacecraft GO/No GO Poll 9:46:00
00:06 00:16 NAM Poll 9:46:00
00:06 00:16 SMD Poll 9:46:00
00:05 00:15 Fuel Fill Sequence Complete 9:47:00
00:05 00:15 Water Deluge System actuation Pressure Adjustment 9:47:00
00:05 00:15 Cenataur LOX at Flight Level 9:47:00
00:05 00:15 Centaur LH2 at Flight Level 9:47:00
00:04 00:13 NLM Poll 9:49:00
HOLDING 00:09 Launch Director Final Poll 9:53:00
  >>>> SAFE L-9MIN CONFIGURATION FOR EXTENDED HOLDS <<<<
Variable 00:07 Spacecraft Status Check 9:55:00
Hold 00:06 Spacecraft on internal Power 9:56:00
  00:06 LD GO to Launch 9:56:00
  00:05 Range Clear Validation 9:57:00
COUNTING 00:04 Hazardous Gas Monitoring Complete 9:58:00
00:04 00:04 Automatic Sequence Begins 9:58:00
00:04 00:04 Atlas LOX Replenish Terminated 9:58:00
00:04 00:04 Atlas LOX Tank Pressurization 9:58:00
00:03 00:03 Atlas Tanks at Flight Pressure 9:59:00
00:02 00:02 Atlas and Centaur switch to internal Power 10:00:00
00:01:55 00:01:55 CMD Sequence 10:01:05
00:01:50 00:01:50 Centaur Topping Sequence complete 10:01:10
00:01:30 00:01:30 Launch Control System Enabled 10:00:30
00:00:16 00:00:16 Launch Verification 10:01:44
00:00:02.7 00:00:02.7 Main Engine Start 10:01:57
00:00:00.0 00:00:00.0 Booster Ignition 10:02:00
+00:00:01.1 +00:00:01.1 Liftoff 10:02:01

 

Launch Date November 26, 2011
Launch Time 10:02am to 11:45am EST
Launch Site Cape Canaveral Air Force Station
  Space Launch Complex 41
Launch Opportunities Nov 25 to Dec 18
Launch Vehicle Atlas V 541

Launch Window Opens

Links

Launch Vehicle Information
MSL Launch Windows
Ascent Info (Timeline, Ground Track)

Weather
Updated: 11/25/11

Weather: Isolated Showers
Temperature: 62-73°F
Clouds: SCT 035; SCT 300
  Cumulus, Cirrus
Winds  
Direction: 100°
Speed: 18-22KT
Visibility: 7 Miles
Lightning Probability: 10%
Precipitiation Probability: 10%
Prob. of weather rule violations 30%
Concern Cumulus Clouds
  Ceiling
24-Hour Delay 30%
48-Hour Delay 60%

Weather Links

Florida Satellite (Visible): Click Here

Florida Satellite (IR): Click Here

Florida Satellite (False): Click Here

Launch Weather Forecast (PDF File): Click Here

Florida Radar: Click Here


Countdown Timeline Diagram

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Picture
Source: ULA - Launch Press Kit