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![]() Shuttle Endeavour fueled up for Monday launch try BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: July 13, 2009 ![]() ![]() Running a month behind scheduled because of hydrogen leaks, launch pad lightning strikes and stormy weather, the shuttle Endeavour was refueled for a fifth launch try Monday to kick off a 16-day space station construction mission. Forecasters are predicting a 60 percent chance of another delay due to expected afternoon storms. Hoping for the best, engineers began pumping liquid oxygen and hydrogen rocket fuel to the shuttle's external tank at 9:33 a.m. The fueling procedure was completed at 12:37 p.m. when engineers transitioned to "stable replenish" mode. The hydrogen vent line that triggered two launch delays last month is working normally, with no signs of any leakage. If all goes well, commander Mark Polansky, pilot Douglas Hurley, Canadian flight engineer Julie Payette, David Wolf, Christopher Cassidy, Thomas Marshburn and space station flight engineer Timothy Kopra will begin strapping in around 3:30 p.m. for a launch attempt at 6:51:24 p.m. "While we all hope that today's the day, we have a saying that you never know for
sure until the solid rockets light off," Polansky said in a Twitter posting early
today.
The only way to re-attach or replace the debonded cover is to move a protective gantry back in place around the shuttle. Engineers decided not to do that before today's launch attempt, but any significant rain at the pad likely would trigger a delay. Water trapped in the nozzle could turn to ice in space and possibly damage the thruster. As it now stands, NASA must get Endeavour off the pad by Tuesday to carry out a full-duration five-spacewalk mission. A Russian Progress resupply ship is scheduled for launch July 24 and while it can "loiter" in orbit for five days, it must dock by July 29. That means Endeavour must take off by Tuesday to complete a full-duration mission in time to undock by July 28, making way for the Progress. Depending on how today's launch attempt play out, NASA could opt to make a launch attempt Wednesday, but the mission likely would have to be shortened by one day. The forecast for Tuesday is 60 percent no-go, improving to 60 percent go on Wednesday. If the shuttle doesn't get off by Tuesday or Wednesday at the latest, the flight likely will slip to July 26 or 27. Here is the remainder of today's countdown (in EDT; best viewed with fixed-width font): EDT...........EVENT Monday, July 13 01:30 PM......NASA TV coverage begins 02:29 PM......Final crew weather briefing 02:39 PM......Crew suit up begins 02:56 PM......Resume countdown (T-minus 3 hours) 03:01 PM......Crew departs O&C building 03:31 PM......Crew ingress 04:21 PM......Astronaut comm checks 04:46 PM......Hatch closure 05:16 PM......White room closeout 05:36 PM......Begin 10-minute built-in hold (T-minus 20m) 05:46 PM......NASA test director countdown briefing 05:46 PM......Resume countdown (T-minus 20m) 05:47 PM......Backup flight computer to OPS 1 05:51 PM......KSC area clear to launch 05:57 PM......Begin final built-in hold (T-minus 9m) 06:27 PM......NTD launch status verification 06:42:24 PM...Resume countdown (T-minus 9m) 06:43:54 PM...Orbiter access arm retraction 06:46:24 PM...Launch window opens 06:46:24 PM...Hydraulic power system (APU) start 06:46:29 PM...Terminate LO2 replenish 06:47:24 PM...Purge sequence 4 hydraulic test 06:47:24 PM...IMUs to inertial 06:47:29 PM...Aerosurface steering profile 06:47:54 PM...Main engine steering test 06:48:29 PM...LO2 tank pressurization 06:48:34 PM...GOX vent arm retraction 06:48:49 PM...Fuel cells to internal reactants 06:48:54 PM...Clear caution-and-warning memory 06:49:24 PM...Crew closes visors 06:49:27 PM...LH2 tank pressurization 06:50:34 PM...Orbiter to internal power 06:50:53 PM...Shuttle computers take control of countdown 06:51:03 PM...SRB steering test 06:51:17 PM...Main engine start (T-6.6 seconds) 06:51:24 PM...SRB ignition (LAUNCH)
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