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Early hours of Endeavour countdown going well BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: March 8, 2008 The shuttle Endeavour's countdown is ticking smoothly through its initial stages, with engineers checking out the ship's avionics systems and gearing up to pump liquid oxygen and hydrogen aboard early Sunday to power the orbiter's electricity generating fuel cells. With forecasters predicting a 90 percent chance of good weather, launch remains on track for 2:28:12 a.m. Tuesday. The only technical issue going into the countdown was trouble with the shuttle's high-power UHF radio, which serves as a backup to the ship's S-band satellite communications system. Overnight, engineers isolated the problem to an amplifier in the high-power section of the UHF transmitter. Because two low-power UHF amplifiers are fully operational, NASA managers cleared Endeavour for launch as is. "All of our systems are in good shape, our countdown work is on schedule, I have no real issues to report," said NASA Test Director Charlene Blackwell-Thompson. "Our team is ready and we're all looking forward to Tuesday's launch." A cold front swept across the spaceport early today, bringing torrential rain and high winds. But the clouds began clearing out this morning as the front pushed through and while shuttle weather officers expected breezy conditions throughout the day, the forecast for launch early Tuesday remains 90 percent "go." "We've had some interesting weather over the past 24 hours," said forecaster Todd McNamara. "We had thunderstorms on and off until about (3 a.m.) local this morning. As they passed through, we experienced about a quarter to an inch of rain from the northern to the southern portions of Kennedy Space Center and we've seen gusts up to around 39 knots on some of our local wind towers. "Now that that system has pushed through, we're going to see high pressure build back in. Over the next 24 to 48 hours, that high pressure system back behind the front will continue to move through the area and kind of dominate our region and by launch day ... we'll be under very favorable conditions." With only a slight chance of low ceilings, forecasters are predicting a 90 percent chance of good weather, with scattered clouds at 3,000 and 20,000 feet and winds out of 40 degrees at eight knots with gusts up to 12 knots. Crosswinds at the shuttle's emergency runway are expected to be well within limits and good conditions are expected at emergency landing sites in Europe. The forecast for Wednesday is 70 percent go with a 60 percent chance of acceptable conditions on Thursday. Here are countdown highlights leading up to Tuesday's launch (in EST/EDT): EDT...........EVENT Sat 03/08/08 02:30 AM......Call to stations 03:00 AM......Countdown begins 01:00 PM......Fuel cell reactant load preps 06:40 PM......MEC/SRB power up 07:00 PM......Clear crew module 07:00 PM......Begin 4-hour built-in hold 07:45 PM......Clear blast danger area 07:45 PM......Orbiter pyro-initiator controller test 07:55 PM......SRB PIC test 08:55 PM......Master events controller pre-flight test 11:00 PM......Resume countdown Sun 03/09/08 12:30 AM......Fuel cell oxygen loading begins 02:00 AM......Switch to Eastern Daylight Time (GMT-4) 04:00 AM......Fuel cell oxygen load complete 04:00 AM......Fuel cell hydrogen loading begins 06:30 AM......Fuel cell hydrogen loading complete 07:30 AM......Pad open; ingress white room 08:00 AM......Begin 4-hour built-in hold 08:00 AM......Crew module clean and vacuum 08:30 AM...... Fuel cell loading boom disconnected 10:00 AM......Secure mobile launch platform interior 12:00 PM......Countdown resumes 12:00 PM......Main engine preps 12:30 PM......Master event controllers 1 and 2 on; avionics system checkout 01:00 PM......Remove OMS engine covers, throat plugs 01:30 PM......Deflate rotating gantry dock seals; tile inspection 02:00 PM......Tile inspection 06:00 PM......Tail service mast prepped for fueling 08:00 PM......Begin 14-hour 3-minute hold 09:30 PM......OIS communications check 10:15 PM......Crew weather briefing 10:20 PM......JSC flight control team on station 11:30 PM......Comm system activation Mon 03/10/08 12:00 AM......Crew module voice checks 12:30 AM......Launch pad debris inspection 01:00 AM......Flight crew equipment late stow 05:00 AM......Service gantry rotated to park position 06:00 AM......Final heat shield inspection 07:00 AM......Ascent switch list 10:03 AM......Resume countdown 10:03 AM......Astronaut support personnel cockpit config 10:23 AM......Pad clear of non-essential personnel 10:23 AM......Hydraulic power system avionics test 11:13 AM......Fuel cell activation 12:03 PM......Booster joint heater activation 12:33 PM......MEC pre-flight bite test 12:48 PM......Tanking weather update 01:33 PM......Final fueling preps; launch area clear 02:03 PM......Red crew assembled 02:48 PM......Fuel cell integrity checks complete 03:03 PM......Begin 2-hour built-in hold (T-minus 6 hours) 03:13 PM......Safe-and-arm PIC test 03:58 PM......Crew wakeup 04:03 PM......External tank ready for loading 04:18 PM......Mission management team tanking meeting 05:03 PM......Resume countdown (T-minus 6 hours) 05:03 PM......Liquid oxygen (LO2), liquid hydrogen (LH2) transfer line chilldown 05:13 PM......Main propulsion system chill down 05:13 PM......LH2 slow fill 05:43 PM......LO2 slow fill 05:48 PM......Hydrogen ECO sensors go wet 05:53 PM......LO2 fast fill 06:03 PM......LH2 fast fill 07:58 PM......LH2 topping 08:03 PM......LH2 replenish 08:03 PM......LO2 replenish 08:03 PM......Begin 2-hour 30-minute built-in hold (T-minus 3 hours) 08:03 PM......Closeout crew to white room 08:03 PM......External tank in stable replenish mode 08:18 PM......Astronaut support personnel comm checks 08:48 PM......Pre-ingress switch reconfig 08:55 PM......Crew breakfast/photo op (recorded) 09:30 PM......NASA television launch coverage begins 09:58 PM......Final crew weather briefing 10:08 PM......Crew suit up begins 10:33 PM......Resume countdown (T-minus 3 hours) 10:38 PM......Crew departs O&C building 11:08 PM......Crew ingress 11:58 PM......Astronaut comm checks Tue 03/11/08 12:13 AM......Hatch closure 12:53 AM......White room closeout 01:13 AM......Begin 10-minute built-in hold (T-minus 20m) 01:23 AM......NASA test director countdown briefing 01:23 AM......Resume countdown (T-minus 20m) 01:24 AM......Backup flight computer loads OPS 1 software 01:28 AM......KSC area clear to launch 01:34 AM......Begin final built-in hold (T-minus 9m) 02:04 AM......NTD launch status verification 02:19:12 AM...Resume countdown (T-minus 9m) 02:20:42 AM...Orbiter access arm retraction 02:23:12 AM...LAUNCH WINDOW OPENS 02:23:12 AM...Hydraulic power system (APU) start 02:23:17 AM...Terminate LO2 replenish 02:24:12 AM...Purge sequence 4 hydraulic test 02:24:12 AM...Inertial measurement navigation units to inertial 02:24:17 AM...Control surfaces steering test 02:24:42 AM...Main engine steering test 02:25:17 AM...LO2 tank pressurization 02:25:37 AM...Fuel cells to internal reactants 02:25:42 AM...Clear caution-and-warning memory 02:26:12 AM...Crew closes visors 02:26:15 AM...LH2 tank pressurization 02:27:22 AM...SRB joint heater deactivation 02:27:41 AM...Shuttle flight computers take control of countdown 02:27:51 AM...SRB steering test 02:28:05 AM...Main engine start (T-6.6 seconds) 02:28:12 AM...Booster ignition (LAUNCH)
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VIDEO:
SATURDAY'S COUNTDOWN STATUS BRIEFING 