STS-127 Updates

[tblaxland]

I seriously think that it is time for NASA to get a new launch vehicle finally.

Like they're not already... :dry:

 

[agentgonzo]

Launch is delayed until NET 11th July due to the beta cutout for the orbiter whilst at the ISS (basically it will spend too much of its orbit in the sun and overheat).

It should give them plenty of time to look into the H2 leaks.

 

[FordPrefect]

I am really delighted to learn that the launch of LRO is no longer delayed now because of the shuttle. LRO is going to be a really exciting mission.

 

[DaveS]

Bill Harwood's latest STS-127 story: http://spaceflightnow.com/shuttle/sts127/090619update/
To summarize(but I do recommend that you read it as iy contains some other bits of information):

• The gaseous hydrogen(GH2) leaks that have been seen recently at the Grounnd Umbilical Carrier Plate(GUCP)/External Tank Carrier Assembly(ETCA) is now thought to be caused by a "clocking" misalignment on ETCA.
• The use of a new 2-part flexible seal could resolve this misalignment.
• During the weekend, pad workers will take detailed measurements of the current GUCP/ETCA for confirmation of this hypothesis.
• Then next week they'll once again take the GUCP apart again and quite possible demate the actual GUCP from the ETCA on the Endeavour's ET-131.
• An Integrated Tanking Test(S0037) is planned for sometime at the end of this month ahead of a July launch.

 

[ryan]

I am really delighted to learn that the launch of LRO is no longer delayed now because of the shuttle. LRO is going to be a really exciting mission.

Its sort of the which takes priority the unmanned or manned mission arguement that has been going on for ages.

And becuase i dont bother to read any of the last posts, has any one seen the post scrub conference they said the leak was the size of a tip of a pen.

 

[agentgonzo]

Nasa:

Engineers Narrow In on Cause of Endeavour Hydrogen Leak

Sun, 21 Jun 2009 03:40:29 PM GMT

Space Shuttle Program Manager John Shannon says engineers believe they now understand why a hydrogen gas vent line has been leaking, causing shuttle Endeavour's STS-127 mission to be postponed twice. He says a plate that attaches the vent line to Endeavour's external fuel tank is slightly misaligned and that's allowing a small leak to happen during the fueling process.

Teams at NASA Kennedy Space Center's Launch Pad 39A are taking precise measurements of the attaching plate during the weekend before crews disassemble it, realign the plate and install a new set of seals to fix the leak. Shannon also says technicians are preparing to test the repair plan by filling Endeavour's external tank with liquid hydrogen and liquid oxygen in the next week and a half, just as they would for a launch. This "tanking test" will confirm whether the repairs will work before another launch attempt is made. Hydrogen leaks in the vent line postponed Endeavour's launch attempts June 13 and 17, delaying its 16-day flight to the International Space Station. If the repairs are successful, Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m. EDT.

At NASA's Johnson Space Center in Houston, STS-127’s seven astronauts are taking the weekend off before resuming their mission training Monday

 

[DaveS]

Some techs at GUCP:

 

[dougkeenan]

Who would have ever thought hydrogen valves needed alignment? Live and learn.

 

[Orbinaut Pete]

Who would have ever thought hydrogen valves needed alignment? Live and learn.

I think this whole issue is just an example of why jobs should be done properly the first time around.

If an investigation had been done after the STS-119 hydrogen leak, the issue may well have been found then, and Endeavour might be in space now.

With 8 more Shuttle flights planned, and only a 1 and a quarter years left in the Shuttle program, the temptation to rush things through is great. But, every time NASA have ignored problems in the past, even small problems, it has led to disasters (Challenger being SRB O-Ring seals, Columbia being ET foam loss). While I admit, a pad hydrogen leak is relatively danger-free, it just makes me wonder what other problems are currently being overlooked, with the hope being that the program will end before they become serious.

I know that clocks are ticking for the remaining Shuttle missions, and that 8 missions in just over 1 year is a very ambitious target, but that is no excuse to get sloppy. NASA need to stay sharp. It would be a great shame if, instead of ending on the high flight rate for which it was designed, the Shuttle program ended on another disaster.

 

[tblaxland]

I think this whole issue is just an example of why jobs should be done properly the first time around.

If an investigation had been done after the STS-119 hydrogen leak, the issue may well have been found then, and Endeavour might be in space now.

Might is the appropriate word since the evidence is contrary to your speculation:

http://spaceflightnow.com/shuttle/sts127/090619update/

engineers believe Endeavour's problem is a one-time issue related to this particular external tank. A spare vent line carrier plate was attached to external tanks currently in production and no similar clocking problems were found

If there are no "clocking" issues with tanks currently in production then it is unlikely there is a tooling issue and, on balance of probabilities, it is likely that past leaks were also unrelated. Also, if more time was taken on 119, then it is also likely that 127 would not be in space due to flow-on delays.

 

[agentgonzo]

I think this whole issue is just an example of why jobs should be done properly the first time around.

Comments like these always annoy me. One of the (many) reasons why projects fail is because managers/directors expect people to be infallible. Yes, it would be better if all jobs are done properly the first time around, but if you expect this to be the case when you set out then you are destined to fail. Humans are fallible and will make mistakes somewhere along the lines - it's just a fact you have to accept. This is why there should always be procedures in place to detect/fix the problem should they arise - just as the launch checks detected the leak before the launch and resulted in a scrub.

I don't see the scrub as a failing of the launch system. I see it as a success of system in that the errors/problems were detected before they became critical and procedures enacted to fix the issue. The space shuttle is horrendously complicated and I see launch scrubs as a reminder of just how complicated a task Nasa are undertaking and how well they are doing at it.

Rant over

 

[DaveS]

Per NASASpaceflight.com the tanking test is set for next Wednesday(July 1), with actual tanking starting at 4 am EDT(0800 UTC).

 

[tblaxland]

If there are no "clocking" issues with tanks currently in production then it is unlikely there is a tooling issue and, on balance of probabilities, it is likely that past leaks were also unrelated.

I take that back:
http://www.nasaspaceflight.com/2009...t-for-next-wednesday-gucp-repair-work-begins/

This problem has been found with six other tanks set to fly, although the misalignment on ET-131 is classed as “the worst”.

Still, I don't think NASA can be criticised on this issue. If this root cause analysis had all been done at STS-119, STS-127 would still likely have been delayed into July. I think the work that went on with the GH2 FCV's prior to STS-119 shows that NASA is well committed to having a safe vehicle.

 

[ryan]

Why is there GUP covered up?

 

[tblaxland]

Why is there GUP covered up?

Its not. The structure you see there on the outside of the external tank is the Ground Umbilical Carrier Plate (GUCP). What has been covered up is the gaseous hydrogen (GH2) quick disconnect (QD) socket. Mostly likely to prevent contamination.

 

[DaveS]

Its not. The structure you see there on the outside of the external tank is the Ground Umbilical Carrier Plate (GUCP). What has been covered up is the gaseous hydrogen (GH2) quick disconnect (QD) socket. Mostly likely to prevent contamination.

Entirely correct. The glossy green area behind the gray GUCP is the External Tank Carrier Assembly(ETCA) which is the umbilical on the tank to which the GUCP is mated to when it is in the VAB vertical checkout cell.

 

[tblaxland]

The glossy green area behind the gray GUCP is the External Tank Carrier Assembly(ETCA) when is the umbilical on the tank to which the GUCP is mated to when it is in the VAB vertical checkout cell.

Sorry that sentence doesn't quite make sense to me, so here is my interpretation: the ECTA is fixed to the ET structure; the GH2 QD socket is mounted in the ECTA; the QD plug is mounted in the GUCP; the GUCP is mated to the ECTA which mates the QD plug and socket. (Very "Dem Bones" isnt it, sing: The thigh bone is connected to the hip bone... Dem bones gonna walk around... )

Is the ECTA is mounted to the ET in the VAB, not MAF?

 

[DaveS]

Sorry that sentence doesn't quite make sense to me, so here is my interpretation: the ECTA is fixed to the ET structure; the GH2 QD socket is mounted in the ECTA; the QD plug is mounted in the GUCP; the GUCP is mated to the ECTA which mates the QD plug and socket. (Very "Dem Bones" isnt it, sing: The thigh bone is connected to the hip bone... Dem bones gonna walk around... )

Is the ECTA is mounted to the ET in the VAB, not MAF?

Just noticed the wording error:

"The glossy green area behind the gray GUCP is the External Tank Carrier Assembly(ETCA) which is the umbilical on the tank to which the GUCP is mated to when it is in the VAB vertical checkout cell."

I hope that makes more sense.

 

[tblaxland]

I hope that makes more sense.

Yes, thank you.

 

[ryan]

NASA Plans "Tanking Test" for Wednesday, July 1

Fri, 26 Jun 2009 02:34:44 AM UTC+1000


At NASA's Kennedy Space Center in Florida, crews continue work to repair a plate that attaches a gaseous hydrogen vent line to space shuttle Endeavour's external fuel tank. Hydrogen leaks in the area of the Ground Umbilical Carrier Plate, or GUCP, postponed Endeavour's launch attempts June 13 and 17, delaying its 16-day flight to the International Space Station. Seals in the GUCP were removed overnight and will be shipped to NASA's Marshall Space Flight Center in Huntsville, Ala. today for inspection.

A "tanking test" is planned for Wednesday, July 1, starting at 7 a.m. EDT to ensure repairs were successful. Endeavour's external tank will be filled with liquid hydrogen and liquid oxygen, just as it is before launch. NASA managers will hold a news conference following the test to discuss the results at approximately 1 p.m. The test will be shown live on NASA television.

Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m.

At NASA's Johnson Space Center in Houston, the STS-127 mission astronauts will spend today in the fixed base simulator brushing up on procedures for their first spacewalk. They'll also rehearse the installation of the Japanese Experiment Facility platform that will be attached as the "porch" for the Kibo science laboratory on Flight Day 4 of the mission.


(This is from the NASA site)

---------- Post added 06-27-2009 at 02:06 AM ---------- Previous post was 06-26-2009 at 05:35 AM ----------

Ground Umbilical Carrier Plate Realigned, Seals Reinstalled

Sat, 27 Jun 2009 05:44:45 AM UTC+1000


At NASA's Kennedy Space Center in Florida, crews continue work to repair a plate that attaches a gaseous hydrogen vent line to space shuttle Endeavour's external fuel tank. Hydrogen leaks in the area of the Ground Umbilical Carrier Plate, or GUCP, postponed Endeavour's launch attempts June 13 and 17, delaying its 16-day flight to the International Space Station. The carrier plate has been realigned and seals have been installed.
On Wednesday, July 1, starting at 7 a.m. EDT, a tanking test will be conducted to ensure repairs were successful. Endeavour's external tank will be filled with liquid hydrogen and liquid oxygen, just as it is before launch. NASA managers will hold a news conference following the test to discuss the results at approximately 1 p.m. The test and news conference will be shown live on NASA television.
Endeavour's next launch attempt is targeted for July 11 at 7:39 p.m.
At NASA's Johnson Space Center in Houston, the STS-127 mission astronauts will resume training Monday, June 29.