Realtime coverage of STS-134 launch countdown (UPDATED)
By WILLIAM HARWOOD
CBS News
07:10 a.m. EDT Update: Astronauts board shuttle
KENNEDY SPACE CENTER, FL--The Endeavour astronauts have strapped in, the shuttle's hatch has been closed and sealed and the countdown is ticking smoothly toward launch at 8:56:28 a.m. EDT GMT-4). The only technical issue so far this morning has been a minor ding to a heat shield tile near the shuttle's side hatch that required a patch by launch pad technicians.
Forecasters, meanwhile, are monitoring a deck of low clouds that could cause problems as launch time approaches.
NASA flight rules forbid a launch if crosswinds at the shuttle's emergency runway exceed 15 knots and if broken clouds below 6,000 feet encroach on the space center. Those rules can be waived if an astronaut flying a shuttle training jet deems the weather acceptable for an emergency return-to-launch-site landing, but only if conditions are only marginally worse than the launch commit criteria as written.
The tile damage appeared minor and technicians at the pad used a tile repair kit to fill in the ding. There are no other technical issues of any significance.
05:45 a.m. EDT Update: Astronauts board shuttle
KENNEDY SPACE CENTER, FL--Commander Mark Kelly and his crewmates began strapping in aboard the shuttle Endeavour Monday to await liftoff on the 134th shuttle mission. There are no technical problems of any significance and forecasters are optimistic about the weather, although low clouds and brisk crosswinds remain a concern.
Kelly, pilot Gregory H. Johnson, Michael Fincke, Gregory Chamitoff, Andrew Feustel and European Space Agency astronaut Roberto Vittori departed crew quarters around 5:10 a.m. EDT (GMT-4), smiling and waving to Kennedy Space Center workers and reporters before entering NASA's "astrovan" for the trip to the pad.
"Dear God, please bless our crew," Fincke said in a morning Twitter update. "Help us in our mission and to return safely home. Please help me not to mess anything up."
Endeavour was grounded April 29 by a short circuit that knocked out one set of fuel line heaters used by auxiliary power unit No. 1, one of three that provide the hydraulic power needed to move the ship's engine nozzles and aerosurfaces. The short eventually was traced to damaged insulation and an exposed conductor on a thermostat.
The thermostat was replaced, along with an avionics control box and wiring between the box and the heaters. The system was activated during fueling Monday, when cryogenic propellants flowing through main engine plumbing caused temperatures in the aft engine compartment to drop, and telemetry showed the heaters were operating normally.
03:00 a.m. EDT Update: Shuttle Endeavour fueled for launch
KENNEDY SPACE CENTER, FL--Working by remote control, engineers loaded the shuttle Endeavour's external tank with a half-million gallons of supercold liquid oxygen and hydrogen rocket fuel early Monday, setting the stage for launch on NASA's next-to-last shuttle mission.
The three-hour fueling procedure began on time at 11:36 p.m . EDT (GMT-4) Sunday when the propellants began moving through transfer lines to the shuttle, flowing through the ship's main propulsion system to condition the main engines to cryogenic temperatures and then into the external tank's hydrogen and oxygen sections. The procedure was completed by 2:36 a.m. Monday when the tank was topped off and fueling transitioned to "stable replenish" mode.
Endeavour's crew -- commander Mark Kelly, pilot Gregory H. Johnson, Michael Fincke, Gregory Chamitoff, Andrew Feustel and European Space Agency astronaut Roberto Vittori -- plans to don their bright orange pressure suits and head for the pad to strap in around 5:41 a.m. The hatch to Endeavour's crew compartment will be closed a few minutes before 7 a.m.
Liftoff is targeted for 8:56:28 a.m., the opening of a five-minute launch window that roughly coincides with the moment Earth's rotation carries pad 39A into the plane of the International Space Station's orbit.
There are no technical problems of any significance at the launch pad and forecasters are continuing to predict a 70 percent chance of acceptable weather. The only concerns are possibly high crosswinds and a slight chance of low clouds.
Here is a list of major remaining countdown events (in EDT; best viewed with fixed-width font):
CBS News
07:10 a.m. EDT Update: Astronauts board shuttle
KENNEDY SPACE CENTER, FL--The Endeavour astronauts have strapped in, the shuttle's hatch has been closed and sealed and the countdown is ticking smoothly toward launch at 8:56:28 a.m. EDT GMT-4). The only technical issue so far this morning has been a minor ding to a heat shield tile near the shuttle's side hatch that required a patch by launch pad technicians.
Forecasters, meanwhile, are monitoring a deck of low clouds that could cause problems as launch time approaches.
 |
| Shuttle forecasters are monitoring a deck of low clouds approaching the Kennedy Space Center. Hoping for the best, Endeavour's six-man crew has strapped in for launch. (Credit: NASA TV) |
NASA flight rules forbid a launch if crosswinds at the shuttle's emergency runway exceed 15 knots and if broken clouds below 6,000 feet encroach on the space center. Those rules can be waived if an astronaut flying a shuttle training jet deems the weather acceptable for an emergency return-to-launch-site landing, but only if conditions are only marginally worse than the launch commit criteria as written.
The tile damage appeared minor and technicians at the pad used a tile repair kit to fill in the ding. There are no other technical issues of any significance.
05:45 a.m. EDT Update: Astronauts board shuttle
KENNEDY SPACE CENTER, FL--Commander Mark Kelly and his crewmates began strapping in aboard the shuttle Endeavour Monday to await liftoff on the 134th shuttle mission. There are no technical problems of any significance and forecasters are optimistic about the weather, although low clouds and brisk crosswinds remain a concern.
 |
| The Endeavour astronauts, led by commander Mark Kelly, right, and pilot Gregory Johnson, left, depart crew quarters and head to launch pad 39A to strap in for launch. (Credit: NASA TV) |
Kelly, pilot Gregory H. Johnson, Michael Fincke, Gregory Chamitoff, Andrew Feustel and European Space Agency astronaut Roberto Vittori departed crew quarters around 5:10 a.m. EDT (GMT-4), smiling and waving to Kennedy Space Center workers and reporters before entering NASA's "astrovan" for the trip to the pad.
"Dear God, please bless our crew," Fincke said in a morning Twitter update. "Help us in our mission and to return safely home. Please help me not to mess anything up."
Endeavour was grounded April 29 by a short circuit that knocked out one set of fuel line heaters used by auxiliary power unit No. 1, one of three that provide the hydraulic power needed to move the ship's engine nozzles and aerosurfaces. The short eventually was traced to damaged insulation and an exposed conductor on a thermostat.
The thermostat was replaced, along with an avionics control box and wiring between the box and the heaters. The system was activated during fueling Monday, when cryogenic propellants flowing through main engine plumbing caused temperatures in the aft engine compartment to drop, and telemetry showed the heaters were operating normally.
03:00 a.m. EDT Update: Shuttle Endeavour fueled for launch
KENNEDY SPACE CENTER, FL--Working by remote control, engineers loaded the shuttle Endeavour's external tank with a half-million gallons of supercold liquid oxygen and hydrogen rocket fuel early Monday, setting the stage for launch on NASA's next-to-last shuttle mission.
 |
| The shuttle Endeavour was loaded with fuel early Monday to set the stage for launch on a space station assembly mission. (Credit: NASA TV) |
The three-hour fueling procedure began on time at 11:36 p.m . EDT (GMT-4) Sunday when the propellants began moving through transfer lines to the shuttle, flowing through the ship's main propulsion system to condition the main engines to cryogenic temperatures and then into the external tank's hydrogen and oxygen sections. The procedure was completed by 2:36 a.m. Monday when the tank was topped off and fueling transitioned to "stable replenish" mode.
Endeavour's crew -- commander Mark Kelly, pilot Gregory H. Johnson, Michael Fincke, Gregory Chamitoff, Andrew Feustel and European Space Agency astronaut Roberto Vittori -- plans to don their bright orange pressure suits and head for the pad to strap in around 5:41 a.m. The hatch to Endeavour's crew compartment will be closed a few minutes before 7 a.m.
Liftoff is targeted for 8:56:28 a.m., the opening of a five-minute launch window that roughly coincides with the moment Earth's rotation carries pad 39A into the plane of the International Space Station's orbit.
There are no technical problems of any significance at the launch pad and forecasters are continuing to predict a 70 percent chance of acceptable weather. The only concerns are possibly high crosswinds and a slight chance of low clouds.
Here is a list of major remaining countdown events (in EDT; best viewed with fixed-width font):
HH...MM...SS...EDT...........EVENT
06...20...00...02:36 AM......Begin 2-hour 30-minute built-in hold (T-minus 3 hours)
06...20...00...02:36 AM......Closeout crew to white room
06...20...00...02:36 AM......External tank in stable replenish mode
06...17...00...02:39 AM......Ascent flight control team on console
06...05...00...02:51 AM......Astronaut support personnel comm checks
05...35...00...03:21 AM......Pre-ingress switch reconfig
05...26...00...03:30 AM......NASA TV launch coverage begins
04...25...00...04:31 AM......Final crew weather briefing
04...15...00...04:41 AM......Crew suit up begins
03...50...00...05:06 AM......Resume countdown (T-minus 3 hours)
03...45...00...05:11 AM......Crew departs O&C building
03...15...00...05:41 AM......Crew ingress
02...25...00...06:31 AM......Astronaut comm checks
02...00...00...06:56 AM......Hatch closure
01...30...00...07:26 AM......White room closeout
01...10...00...07:46 AM......Begin 10-minute built-in hold (T-minus 20m)
01...00...00...07:56 AM......NASA test director countdown briefing
01...00...00...07:56 AM......Resume countdown (T-minus 20m)
00...59...00...07:57 AM......Backup flight computer to OPS 1
00...55...00...08:01 AM......KSC area clear to launch
00...49...00...08:07 AM......Begin final built-in hold (T-minus 9m)
00...24...00...08:32 AM......NTD launch status verification
00...09...00...08:47:28 AM...Resume countdown (T-minus 9m)
00...07...30...08:48:58 AM...Orbiter access arm retraction
00...05...00...08:56:28 AM...Launch window opens (placeholder; not needed for STS-134)
00...05...00...08:51:28 AM...Hydraulic power system (APU) start
00...04...55...08:51:33 AM...Terminate LO2 replenish
00...04...00...08:52:28 AM...Purge sequence 4 hydraulic test
00...04...00...08:52:28 AM...IMUs to inertial
00...03...55...08:52:33 AM...Aerosurface profile
00...03...30...08:52:58 AM...Main engine steering test
00...02...55...08:53:33 AM...LO2 tank pressurization
00...02...35...08:53:53 AM...Fuel cells to internal reactants
00...02...30...08:53:58 AM...Clear caution-and-warning memory
00...02...00...08:54:28 AM...Crew closes visors
00...01...57...08:54:31 AM...LH2 tank pressurization
00...00...50...08:55:38 AM...SRB joint heater deactivation
00...00...31...08:55:57 AM...Shuttle GPCs take control of countdown
00...00...21...08:56:07 AM...SRB steering test
00...00...07...08:56:21 AM...Main engine start (T-6.6 seconds)
00...00...00...08:56:28 AM...SRB ignition (LAUNCH)