Wednesday, August 26, 2009

Live At KSC: Suspect Valve Passes Five Tests

BLOGGER UPDATE, 9:22 p.m.: NASA managers have decided to go ahead and resume shuttle Discovery's launch countdown at 8:57 a.m. Thursday, aiming to launch the spaceship and seven astronauts at 12:22 a.m. Friday. Engineers will brief NASA's Mission Management Team on valve testing results at a meeting now scheduled to begin at 1 p.m. Thursday. That meeting will be followed at 2:15 p.m. by the MMT's tanking meeting. Propellant-loading tentatively set to begin just before 3 p.m.

The suspect main propulsion system valve on shuttle Discovery passed a series of tests this evening, and NASA engineers now are performing pressure decay tests on an associated manifold.

The eight-inch liquid hydrogen fill-and-drain valve opened and shut as intended when commanded to do so during five separate cycles.

The results bode well for NASA's tentative plans to try to launch Discovery and seven astronauts at 12:22 a.m. Friday on an International Space Station outfitting mission. The agency now plans to pick up the launch countdown at 8:57 a.m. Thursday. A decision on whether to fly as-is will be made during a Mission Management Team meeting at noon Thursday.

The ongoing press decay tests are expected to be completed between 9:30 p.m. and 10 p.m. tonight.

Assuming mission managers decide to press ahead with a launch attempt, here's a list that covers the timing of major countdown milestones:

++9:57 a.m.: Clear Launch Pad.

++10:47 a.m.: Fuel cell activation.

++Noon: Mission Management Team L-0 meeting.

++12:12 p.m.: Clear "Launch Danger Area".

++1:30 p.m.: Crew wake up.

++1:57 p.m.: Countdown enters 1-hr hold at the T-6 hour mark.

++2:00 p.m.: Crew breakfast.

++2:15 p.m.: Mission Management Team meets to give go for tanking.

++2:30 p.m.: Crew final medical checks.

++2:45 p.m.: NASA TV/External Tank fueling coverage.

++2:57 p.m.: Countdown resumes at T-6 hr mark with External Tank loading.

++3:42 p.m.: Liquid Hydrogen Low Level Cutoff (LLCO) sensors go "wet."

++3:57 p.m.: Liquid Hydrogen "fast fill" begins.

++5:12 p.m.: LH2 "topping" begins (gaseous Hydrogen vent valve cycling).

++5:57 p.m.: Countdown enters 2.5-hr hold (T-3 hr mark). ET in stable replenish. Closeout Crew to White Room. Final Inspection Team (FIT) "walkdown."

++6:30 p.m.: Ascent Team on console in Mission Control in Houston.

++6:30 p.m.: Crew photo opportunity (taped for possible playback later).

++LAUNCH COVERAGE BEGINS on NASA TV. Watch Live In The Flame Trench.

++7:52 p.m.: Crew receives weather brief from Ascent Team.

++Crew suits up for launch.

++8:27 p.m.: Countdown resumes at the T-3 hour mark.

++8:32 p.m.: Crew departs Operations & Checkout Building for Launch Pad 39A.

++Mission Management Team on console in the Launch Control Center at KSC.

++9:02 p.m.: Crew begins to board Discovery.

++9:22 p.m.: T-38 weather reconnaissance (Chief Astronaut Steve Lindsey).

++10:17 p.m.: Discovery's hatch is closed and latched for launch.

++10:37 p.m.: Shuttle Training Aircraft weather reconnaissance (Lindsey).

++10:47 p.m.: White Room Closeout.

++11:07 p.m.: Countdown enters a 10-min hold at the T-20 minute mark.

++11:17 p.m.: Countdown resumes at the T-20 minute mark.

++11:28 p.m.: Countdown enters 45-minute hold at the T-9 minute mark. MMT conducts final "Go/No-Go" poll for launch.

++12:13 a.m.: Countdown resumes at the T-9 minute mark.

++12:22 a.m.: Launch.

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