SCRUB: STS-119: LAUNCH ATTEMPT 1 and interim processing coverage

[astrobrian]

NASA just tweeted the following:


At 2:37 p.m. EDT today's launch attempt was scrubbed. Try again in 24 hours. The cause is a hydrogen leak at an attach point to the orbiter.

Does this description fit the information you have or is their 24 hour slip too optimistic?

That would seem to indicate the bipod would it not?

[cb6785]

It definetly get's hotter if we wanna get the full mission duration.

[NavySpaceFan]

It seems that everything that can happen to delay launch has happened.

Nah, I put this in the "it's always something" category.  The pad flow up to this point has been very smooth.

[rsnellenberger]

The leak downstream of the skid, somewhere around the GUCP.

What/which/where/who is "the skid", please?

[Chris Bergin]

The leak downstream of the skid, somewhere around the GUCP.

What/which/where/who is "the skid"?

Asking, might be engineer talk, as I was copying across the notes.

[collectSPACE]

An MMT meeting has been set for 5:00 p.m. EDT.

[Ford Mustang]

An MMT meeting has been set for 5:00 p.m. EDT.

I'll provide a live transcription of the event.

[Chris Bergin]

An MMT meeting has been set for 5:00 p.m. EDT.

I'll provide a live transcription of the event.

MMT meetings are internal. A post-MMT presser would be what you're thinking.

[Ford Mustang]

An MMT meeting has been set for 5:00 p.m. EDT.

I'll provide a live transcription of the event.

MMT meetings are internal. A post-MMT presser would be what you're thinking.

Right, sorry.  Rushed home for coverage to find out they scrubbed, kinda in a downer mood!

[Ronsmytheiii]

The Hydrogen Vent Line Access Arm is used to mate the External Tank (ET) Ground Umbilical Carrier Plate (GUCP) to the launch pad hydrogen vent line. The GUCP provides support for plumbing and cables, called umbilicals that transfer fluids, gases, and electrical signals between two pieces of equipment.

During Shuttle fueling operations, hazardous hydrogen gas is vented from a fuel tank inside the ET. This gas travels through the GUCP and vent line over to a flare stack located a safe distance from the Shuttle. The flare stack is a tall pipe with a flame igniter at top that safely burns away the hydrogen gas.

The Hydrogen Vent Line Access Arm also provides contingency access to the ET. It is retracted several hours before launch, leaving the umbilical attached. When the solid rocket boosters ignite, the umbilical carrier plate releases from the ET and falls back against the tower. A curtain of sprayed water protects it from flames produced by the Shuttle engines during launch.

http://enterfiringroom.ksc.nasa.gov/systemSwingArm.htm

[rsnellenberger]

The leak downstream of the skid, somewhere around the GUCP.

What/which/where/who is "the skid"?

Asking, might be engineer talk, as I was copying across the notes.

I'm now guessing that it's the attach plate itself, which would be good in that "downstream" would indicate that it's not in the vehicle or in the attach points to the orbiter.  If so, might not be as hard to pin down as those earlier H2 leaks in the ET/Orbiter umbilicals (STS-35?). 

[rsnellenberger]

An MMT meeting has been set for 5:00 p.m. EDT.

I'll provide a live transcription of the event.

MMT meetings are internal. A post-MMT presser would be what you're thinking.

Right, sorry.  Rushed home for coverage to find out they scrubbed, kinda in a downer mood!

We were all prepared to be very impressed 

[Namechange User]

The leak downstream of the skid, somewhere around the GUCP.

What/which/where/who is "the skid"?

Asking, might be engineer talk, as I was copying across the notes.

I'm now guessing that it's the attach plate itself, which would be good in that "downstream" would indicate that it's not in the vehicle or in the attach points to the orbiter.  If so, might not be as hard to pin down as those earlier H2 leaks in the ET/Orbiter umbilicals (STS-35?). 

It is not in the orbiter or at the umbilicals.  It is in the GUCP area, hopefully just a bad alignment or seal. 

[glanmor05]

Is it too early or does anyone know where the count will commence from and at what time?  Assuming, tanking therefore 6 hours?

[padrat]

except the skid is downstream of the GUCP, not the other way around.

[hobson911]

Thanks Pad rat for the photo and pointing out the locations on the FSS

[Chris Bergin]

Is it too early or does anyone know where the count will commence from and at what time?  Assuming, tanking therefore 6 hours?

Wait for the MMT. We're hearing its 18 hours just to boil off the tank if it needs to be inert. That makes 24 hours tight, but it depends on how much troubleshooting is required. Bottom line is they are still draining the tank, wait for the MMT.

[rsnellenberger]

Thanks Pad rat for the photo and pointing out the locations on the FSS

Ditto...

[violin1238]

I have been very skeptical of this particular external tank. I don't know why. I wasn't confident when Atlantis was at the pad with ET-127 back in September and know I feel the same with Discovery at the pad  with ET-127.

[Paul Howard]

Looks like the main article on site updated with some images too.
http://www.nasaspaceflight.com/2009/03/sts-119-in-prep-for-tanking-following-engineering-overview-for-crew/