STS-119 processing

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ozspace

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Looks like they have removed the Hydrogen line and are working on the tank, replacing a seal?
2n86kp5.jpg

You can get screen snaps here
http://science.ksc.nasa.gov/shuttle/cou ... 1large.jpg
 
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bobw

Guest
It wasn't long until they switched to a camera showing 3 tanker trucks back up to a pipe with 4 hoses and unloaded something. The trucks left after about an hour but the camera stayed there so I went to sleep. This morning the pipe is gone and that's what I stayed up so late to see.

Spaceflight Now is still saying it is a seal, at least they don't mention a valve.
Based on past repair experience, a seal in the vent line system must be tightened down after reassembly and allowed to sit for an extended period to correct for possible misalignments during installation. That would have delayed launch to Monday. But engineers decided today they could properly torque the seal in place faster than that, and mission managers opted to press for a Sunday launch.

The Flame Trench has added another story to the one from last night and even has a picture of the valve and a much bigger picture here: http://www.floridatoday.com/content/blo ... 713726.jpg
Valve1-712918.jpg


If that thing is at the end of the pipe in your first picture it must be buried under a bunch of insulation because I can't see any flanges down there. If it is inside the pipe I can't figgure out how they can tighten the bolts on what would be the deep down inside flange.

I am glad the picture is back, maybe I can see the arm come back up. Glad I got some sleep too :)
 
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MeteorWayne

Guest
Teams have developed a plan for troubleshooting and repairing the Ground Umbilical Carrier Plate (GUCP) interface, where gaseous hydrogen leaked during Wednesday's launch attempt. This morning, crews will begin replacing the 7-inch quick disconnect and two seals, one on the external tank side and one on the ground equipment side. The interface then will be retested and leak checked. The teams are confident in the plan and are working toward a Sunday, March 15 launch at 7:43 p.m. EDT. The Mission Management Team will meet on Saturday at 1 p.m. to review the data and the progress of the teams, and make a final determination on the launch.

A request has been sent to the Eastern Range for a possible Sunday attempt.

There will be an STS-119 Launch Status Update on NASA TV at 10:30 a.m. EDT today and a Prelaunch News Conference will be held no earlier than 3 p.m. EDT following Saturday's MMT.
 
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bobw

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I suppose the only way I'm going to understand is to watch the press conference. Maybe not even then :)

ozspace lucked out getting that new picture. I saw it too for a minute but now it shows the rotating service structure.
 
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MeteorWayne

Guest
scribblenotes

OK, plan is in work. They are going to replace all the seals. So far no smoking gun. Thye did an ambient temp leak test today, which as expected showed no leak. The problem occurred Wednesday after the gas leaving the ET was very cold (cryo temps), so since they can't test that, the plan is just to replace everything, retank and plan to fly Sunday evening. Of course, they will be monitoring the situation as usual (well really with a bit more intense interest :) )They will be using an accelerated torquing schedule to get to Sunday launch. That procedure is being tested right now. Work on seals should be done by this afternoon (4-6 PM EDT).
Normally, plan calls for retorquing the seal connections after 30 hour wait, however engineering data has indicated most of the relaxation of the seals occurs within 45 minutes, so they will do 2 3 hour retorques.

Plan is to pick up the count at 4:11 AM EDT Sunday morning, with tanking beginning at 10:18 Sunday AM. Launch window opens at 7:38. This will be a 13 day mission (For a Sunday Launch) so EVA 4 will be dropped.

Weather is 80% go Sunday, 70% go Monday, and 40% go Tuesday---after that is the reasonably hard cutout for the Soyuz. US abort sites have good wx, 2 of 3 TAL sites good all days.

MW
 
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astronaut23

Guest
Normally, plan calls for retorquing the seal connections after 30 hour wait, however engineering data has indicated most of the relaxation of the seals occurs within 45 minutes, so they will do 2 3 hour retorques.

They should stick to the normal plan. I don't want to watch another one of these things blow up. :(
 
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Rhyolite

Guest
astronaut23":bfip1sbr said:
Normally, plan calls for retorquing the seal connections after 30 hour wait, however engineering data has indicated most of the relaxation of the seals occurs within 45 minutes, so they will do 2 3 hour retorques.

They should stick to the normal plan. I don't want to watch another one of these things blow up. :(

That comment is unwarranted and uninformed
 
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MeteorWayne

Guest
Indeed it is. Astronaut23, if you had read what I said, they are quite comfortable with doing this providing the additional testing underway shows that it works fine.

In any case, it would never be a threat to the vehicle, since the plainly stated fact is, that if it leaks again, the countdown stops. If you understood it, this problem is only a threat while they are on the ground, and the detectors in place will let them know during the tanking operation, as they did last time, if there is a problem. If it doesn't leak, there is no threat to the vehicle at all. If it does, the countdown stops.
 
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montmein69

Guest
Maybe have they found what's wrong :

http://www.nasa.gov/mission_pages/shuttle/main/

Early this morning, while installing the replacement seven-inch quick disconnect, crews discovered the Ground Umbilical Carrier Plate (GUCP) was not aligned properly with the external tank. The left and right pivot seat was not fully connecting to the external tank's pin receptacle sleeve at the bottom of the GUCP. Crews now are in the process of checking alignments and making adjustments to get a proper fit. Leak checks will be performed following the adjustments.
 
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MeteorWayne

Guest
Discovery, Weather Looking Good For Launch
Sat, 14 Mar 2009 03:07:00 PM EDT


NASA managers said Saturday that space shuttle Discovery is ready for Sunday’s launch opportunity as repairs on a leaking gaseous hydrogen vent line are moving along smoothly.

“I think we’re in really good shape,” said Mike Moses, chairman of the Mission Management Team that reviewed the shuttle’s readiness.

Mike Leinbach, shuttle launch director, said the work to replace a suspect quick disconnect assembly on the launch pad is about three hours behind schedule, but that will not delay the countdown. Leak checks will be performed later tonight.

“We feel really good and we’re really excited about launching tomorrow,” Leinbach said.

The weather forecast continues to call for an 80 percent chance of acceptable conditions, said Kathy Winters, shuttle weather officer.

Launch controllers will begin preparing to pump fuel and oxygen into the external tank Sunday at 10:18 a.m. EDT. Launch time is 7:43 p.m.
 
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MeteorWayne

Guest
Tanking is underway, no problems so far.

Based on the time of occurrence of the problem during Wednesday's tank fill, that would translate to about 12:30 PM EDT (1630 UT/GMT)
 
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MeteorWayne

Guest
"Fueling of the external tank continues on schedule. The operation began with chill down at 10:20 a.m. EDT and the flow of liquid hydrogen and liquid oxygen at 10:30. An hour into the three-hour process, both tanks are about 26 percent full. The "topping" mode of the liquid hydrogen section begins at about 12:35 p.m. "

MW- IIRC, the problem occurred just before the stable replenishment, so my time estimate earlier seems about right.
 
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MeteorWayne

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Looks good. Now past the point where the problem occurred Wednseday, and no leakage :) :) :)
 
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MeteorWayne

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Uhh ohh. A potential minor (so far) problem A drop in helium pressure on 1 or 4 sensors. I'll update as they give us more info. IIRC, helium is used in various systems to maintain pressure. This is not related to the LH or LOX tanks.
 
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MeteorWayne

Guest
"Teams are monitoring a drop in helium pressure in one of four liquid hydrogen gap measurement plates at the liquid umbilical disconnect where the orbiter connects to the tank. The gap measurement plate maintains a possive purge between the external tank and the orbiter interface to prevent potential ice formation and keeps electrical equipment at the right temperature. All four gap measurements are working, but one has dipped slightly below requirements. The condition will be monitored but is not currently expected to impact tonight's launch. Teams also are exploring the option of manually adjusting the ground system valve in the mobile launcher platform to assist in increasing the pressure."
 
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bobble_bob

Guest
nimbus":1dael2wh said:
And they never found exactly what was leaking this wednesday?

Seems not. Just a case of replacing everything that they think may have caused it and hope for the best

Seems to have worked
 
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bobble_bob

Guest
Ken Ham helping the crew get strapped in. I met him and shook his hand last year :cool:
 
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3488

Guest
Looks like Discovery's crew have arrived at Discovery after the ride from the crew quarters on the Astrovan.

From Spaceflightnow.com.

Justin Ray.

2008 GMT (4:08 p.m. EDT)
Discovery's crew has arrived at launch pad 39A. The AstroVan came to a stop on the pad surface near the Fixed Service Structure tower elevator that will take the seven-man crew to the 195-foot level to begin boarding the shuttle.

2002 GMT (4:02 p.m. EDT)
The AstroVan is passing the 52-story Vehicle Assembly Building where Discovery was attached to its external tank and solid rocket boosters and the adjacent Launch Control Center.

The Press Site is located across the street, and reporters went outside to watch at the passing convoy. This is a launch day tradition to say farewell and good luck to the astronaut crews.

1953 GMT (3:53 p.m. EDT)
Commander Lee Archambault, pilot Tony Antonelli, mission specialists Joe Acaba, Steve Swanson, Ricky Arnold, John Phillips and station-bound astronaut Koichi Wakata just departed the Kennedy Space Center crew quarters to board the AstroVan for the 20-minute ride from the Industrial Area to launch pad 39A on the edge of the Atlantic Ocean.

Guess preparations are going smoothly then, other wise the crew would not have boarded the Astrovan for the ride to Discovery.

Andrew Brown.
 
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bobble_bob

Guest
Good to see alot of questions coming from the UK during this countdown coverage. I was beginning to think no one else cared about a shuttle launch over here
 
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3488

Guest
bobble_bob":14ncw08s said:
Good to see alot of questions coming from the UK during this countdown coverage. I was beginning to think no one else cared about a shuttle launch over here

I certainly care Bob.

I know manned spaceflight is not my main area, unmanned planetary exploration is, does not mean that I do not care or am not interested. I am very interested & care very much for a successful safe launch, successful mission & a safe return.

Nice photo of the crew posing out side of the Astrovan earlier.

213834main_119_walkout_2_720.jpg
.

Andrew Brown.
 
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