1115a 6/7 Update: Wx 80 percent 'go' =================================

CBS NEWS STS-117 STATUS REPORT: 23
Posted: 11:05 AM, 6/7/07

By William Harwood
CBS News Space Analyst

Changes and additions:

   SR-21 (06/06/07): MMT clears Atlantis for launch; engineers brace for evening storms, possible hail
   SR-22 (06/06/07): Shuttle dodges severe storms
   SR-23 (06/07/07): Weather improves to 80 percent 'go'

=================================

11:05 AM, 6/7/07, Update: Weather improves to 80 percent 'go' 

Making up lost time after a stormy night at the launch pad, shuttle workers at the Kennedy Space Center expect to have Atlantis ready for blastoff Friday night on a long-delayed space station assembly mission. There are no technical problems at pad 39A and forecasters now predict an 80 percent chance of good weather at launch time.

"After many months of hard work, Atlantis is finally ready to fly," NASA Test Director Steve Payne told reporters today.

If all goes well, a protective gantry will be rolled away from Atlantis at 10:30 p.m. and engineers will begin pumping a half-million gallons of rocket fuel into the shuttle's external tank starting shortly after 9 a.m. Friday.

Commander Rick Sturckow and his crewmates - pilot Lee Archambault, flight engineer Steve Swanson, Patrick Forrester, Danny Olivas, Jim Reilly and Clay Anderson - plan to begin strapping in around 4:15 p.m. Liftoff is targeted for 7:38 p.m., roughly the moment Earth's rotation carries the launch pad into the plane of the space station's orbit.

Thunderstorms Wednesday evening delayed work to load the shuttle's internal tanks with liquid hydrogen and oxygen to power the ship's electricity producing fuel cells. But Payne said the launch team was able to make up lost time using built-in holds in the countdown and no major problems were expected.

"We did have some significant weather in the area last night," said shuttle weather officer Kathy Winters. "It did delay the ops a little bit, but generally, all the weather came together over the western portion of Melbourne and back toward the west. There was three-quarter-inch hail down in West Melbourne, but no hail here at Kennedy Space Center."

Atlantis originally was scheduled for launch March 15, but the flight was delayed three months after a freak hail storm caused extensive damage to the top of the shuttle's external fuel tank. That damage has now been repaired and engineers say they are confident the tank's foam insulation will stand up to the thermal and aerodynamic rigors of launch without shedding any potentially dangerous debris.

Today, Winters improved the launch forecast for Friday from 70 percent "go" to an 80 percent chance of favorable weather.

"We think it looks a little bit better," she said. "Yesterday, we thought some inland thunderstorms might still be close enough to affect us, but today we're more confident they'll be more inland. So just a 20 percent chance of KSC weather prohibiting launch."

Emergency runways in California, New Mexico, Spain and France also are expected to be available for use if needed. Should launch be delayed, the probability drops to 70 percent go on Saturday and 60 percent on Sunday.

As of this writing, flight controllers are using 7:38:02 p.m. as the estimated launch time. That may change by a few seconds based on final checks of the station's orbit and a final hold at the T-minus nine-minute mark will be adjusted as required. That said, here are countdown highlights (in EDT; fueling could begin up to a half hour earlier than the listed time):

EDT...........EVENT

Thursday 06/07/07

01:00:00 PM...Begin 13-hour 42-minute hold
03:50:00 PM...JSC flight control team on station
04:00:00 PM...Crew weather briefing
05:00:00 PM...Communications system activation
05:30:00 PM...Crew module voice checks
06:40:00 PM...Flight crew equipment late stow
10:30:00 PM...Rotating service structure to park position
11:30:00 PM...Final tile, debris inspection

Friday 06/08/07

12:30:00 AM...Ascent switch list
02:42:00 AM...Resume countdown

02:42:00 AM...Terminate pad tours
03:02:00 AM...Pad clear of non-essential personnel
03:52:00 AM...Fuel cell activation
04:42:00 AM...Booster joint heater activation
07:27:00 AM...Fuel cell integrity checks complete

07:42:00 AM...Begin 2-hour built-in hold (T-minus 6 hours)
07:52:00 AM...Safe-and-arm system test
08:27:00 AM...Mission management team tanking meeting
09:12:00 AM...Test team ready for fueling
09:42:00 AM...Resume countdown (T-minus 6 hours)

09:42:00 AM...LO2, LH2 transfer line chilldown (could start earlier)
09:52:00 AM...Main propulsion system chill down
09:52:00 AM...LH2 slow fill
10:00:00 AM...Astronaut wakeup
10:22:00 AM...LO2 slow fill
10:27:00 AM...Hydrogen ECO sensors go wet
10:32:00 AM...LO2 fast fill
10:42:00 AM...LH2 fast fill
11:57:00 AM...LH2 topping
12:37:00 PM...LH2 replenish
12:42:00 PM...LO2 replenish

12:42:00 PM...Begin 3-hour built-in hold (T-minus 3 hours)
12:42:00 PM...Closeout crew to white room
12:42:00 PM...External tank in stable replenish mode
12:57:00 PM...Astronaut support personnel comm checks
01:30:00 PM...NASA TV coverage begins
01:45:00 PM...Astronaut photo opportunity
03:07:00 PM...Final crew weather briefing
03:17:00 PM...Astronauts don pressure suits
03:42:00 PM...Resume countdown (T-minus 3 hours)

03:47:00 PM...Crew departs O&C building
04:17:00 PM...Crew ingress
05:07:00 PM...Astronaut comm checks
05:22:00 PM...Hatch closure
06:07:00 PM...White room closeout

06:22:00 PM...Begin 10-minute built-in hold (T-minus 20m)
06:32:00 PM...NASA test director countdown briefing
06:32:00 PM...Resume countdown (T-minus 20m)

06:33:00 PM...Backup flight computer to OPS 1
06:37:00 PM...KSC area clear to launch

06:43:00 PM...Begin final built-in hold (T-minus 9m)
06:54:02 PM...NTD launch status verification
07:29:02 PM...Resume countdown (T-minus 9m)

07:30:32 PM...Orbiter access arm retraction
07:33:02 PM...Hydraulic power system (APU) start
07:33:07 PM...Terminate LO2 replenish
07:34:02 PM...Purge sequence 4 hydraulic test
07:34:02 PM...Inertial measurement units to inertial
07:34:07 PM...Aerosurface movement check
07:34:32 PM...Main engine steering test
07:35:07 PM...LO2 tank pressurization
07:35:27 PM...Fuel cells to internal reactants
07:35:32 PM...Clear caution-and-warning memory
07:36:02 PM...Crew closes visors
07:36:05 PM...LH2 tank pressurization
07:37:12 PM...SRB joint heater deactivation
07:37:31 PM...Shuttle computers take control of countdown
07:37:41 PM...SRB steering test
07:37:55 PM...Main engine start (T-6.6 seconds)
07:38:02 PM...SRB ignition (LAUNCH)

=================================

Quick-Launch Web Links:

CBS News STS-117 Status Reports:
http://www.cbsnews.com/network/news/space/current.html

CBS News STS-117 Quick-Look Page:
http://www.cbsnews.com/network/news/space/currentglance.html

NASA Shuttle Web: http://spaceflight.nasa.gov/shuttle/index.html
NASA Station Web: http://spaceflight.nasa.gov/station/index.html
Spaceflight Now: http://spaceflightnow.com/index.html

=================================



You are currently subscribed to the CBS Space  News mailing list. 
To unsubscribe, go to
http://www.cbsnews.com/htdocs/registration/unsubscribe.php
