srbmod
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787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 7:07 am

This is for continuing the discussion of the (now locked) thread on this topic. 787 may face 6 mo. delay, Vought involved (by KL911 Jun 8 2007 in Civil Aviation)

One last thing, this thread is for discussing the topic at hand, which is the issue with the 787 involving supplier Vought. Any off-topic discussions (like US Corporate Laws and moderator actions) will be deleted and user(s) possibly suspended.
 
DLPMMM
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 8:19 am

If I may be so bold as to ask, why are we bothering with Part 2? At the end of Part 1 someone debunked the entire rumor with a direct statement from a Boeing spokesperson stating that there is no anticipated delay in rollout or EIS, and if there MIGHT be a delay, Boeing would make it public immediately.

I will find the statement in the other thread and edit it into this post.

It was Khobar's post.

Here is the quote and link:

Also: "Contrary to growing rumors that the 787 will be delayed, she said nothing has been encountered so far during final assembly of the first plane -- or with Boeing's partners (the firing of the 787 Vought executive) -- that would delay the official rollout on July 8, first flight or first 787 delivery next May to All Nippon Airways of Japan."

And: "The 787 spokeswoman did say any serious issues that might delay the 787 would be quickly disclosed."

http://blog.seattlepi.nwsource.com/aerospace/archives/116545.asp

[Edited 2007-06-13 01:22:00]
 
kaneporta1
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 8:28 am

From the previous thread....

Quote:
Determinant assembly is thought to be vastly superior, which is why I was very very surprised to see such an error in such a major assembly procedure

I have been saying for some time now that Boeing would encounter out of tolerance step issues. Laying the barrel from the inner mould line means that this step issue will probably be a long term headache for the FAL guys.

Quote:
IIRC, wasn't there an article sometime in the last year that suggested that some of the 737's arriving in Seattle were so out of tolerance that there was a fair amount of hammering and drilling needed to get them assembled?

You can hammer a metallic skin all you like, but a composite one is a very different beast.

I have seen the photos mentioned in that Seattle Times article and I'm very curious how they got it to fit.
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hb88
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2

Wed Jun 13, 2007 8:30 am

Quoting DLPMMM (Reply 1):
If I may be so bold as to ask, why are we bothering with Part 2? At the end of Part 1 someone debunked the entire rumor with a direct statement from a Boeing spokesperson stating that there is no anticipated delay in rollout or EIS, and if there MIGHT be a delay, Boeing would make it public immediately.

As I understand it, the thread relating to the fuselage barrel mismatch was deleted repeatedly and merged into this one (or rather the old thread), so the topic is intended to cover any manufacturing production issues with the 787, not just the rumoured delay.

The current discussion was over the significance of the relatively large mating mismatch in the two fuselage barrels and whether it actually mattered or not.

To me the more relevant issue is whether these sort of tolerance errors are acceptable (even with a recovery plan) in a determinant assembly context. IMO, this should produce much more exacting tolerances and jigging accuracy. However, that hasn't happened in this case and it all looks a bit pear-shaped (no pun intended).

Has anyone covered the pylon/wing interface issue yet?  Wink
 
DLPMMM
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 8:37 am

Quoting HB88 (Reply 3):
The current discussion was over the significance of the relatively large mating mismatch in the two fuselage barrels and whether it actually mattered or not.

To me the more relevant issue is whether these sort of tolerance errors are acceptable (even with a recovery plan) in a determinant assembly context. IMO, this should produce much more exacting tolerances and jigging accuracy. However, that hasn't happened in this case and it all looks a bit pear-shaped (no pun intended).

Then shouldn't this thread be moved to Tech-Ops and renamed "787 Barrel Tolerances", as the title of the thread has nothing to do with the subject matter?
 
hb88
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2

Wed Jun 13, 2007 8:37 am

Quoting Kaneporta1 (Reply 2):
Quote:HB88
"Determinant assembly is thought to be vastly superior, which is why I was very very surprised to see such an error in such a major assembly procedure"

I have been saying for some time now that Boeing would encounter out of tolerance step issues. Laying the barrel from the inner mould line means that this step issue will probably be a long term headache for the FAL guys.

From my review of the images the barrels weren't aligned on the IML in any case. So I don't think it was a layup thickness issue. My take is that the section was cured out-of-round and needed rejigging to the reference part. The problem was this involved pulling out a fair bit of equipping and "pulling" the blown out part into alignment where it was bulging out.

I don't think would be any prospect of machining the edge to fit. The characteristics of the resulting butt joint would be affected massively. Similarly, it's not an issue of filling it. When performance guarantees are as fine as needing specific paint on engine cowlings to achieve certain fuel burn (i'm not sure if this is the case, but such a hoo-ha was made over it I assume it probably is...), an aerodynamic discontinuity such as a fudged butt-joint line could render the airframe unfit for use.
 
travelin man
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 9:48 am

Quoting HB88 (Reply 5):
I don't think would be any prospect of machining the edge to fit. The characteristics of the resulting butt joint would be affected massively. Similarly, it's not an issue of filling it. When performance guarantees are as fine as needing specific paint on engine cowlings to achieve certain fuel burn (i'm not sure if this is the case, but such a hoo-ha was made over it I assume it probably is...), an aerodynamic discontinuity such as a fudged butt-joint line could render the airframe unfit for use.

This quote is further evidence this should be moved to Tech/Ops. I understood not one piece of this statement (maybe I am stupid, but until this point I hadn't thought so.)
 
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Stitch
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 9:57 am

Quoting HB88 (Reply 5):
From my review of the images the barrels weren't aligned on the IML in any case. So I don't think it was a layup thickness issue. My take is that the section was cured out-of-round and needed rejigging to the reference part. The problem was this involved pulling out a fair bit of equipping and "pulling" the blown out part into alignment where it was bulging out.

Based on the pictures from the factory floor I have seen, I am inclined to agree. The pieces mated fine on the right-hand side, but there was a very noticeable gap on the left-hand side.
 
NAV20
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 11:06 am

Quoting HB88 (Reply 3):
The current discussion was over the significance of the relatively large mating mismatch in the two fuselage barrels and whether it actually mattered or not.

This article gives a pretty fair account of the remedial measures taken which appeared to consist of removing and reinstalling some interior fittings (e.g. floor struts) to achieve a fit.

http://seattletimes.nwsource.com/htm...chnology/2003744076_787gaps12.html

That would not appear to raise any strength or safety implications, if that's what you're thinking about. Given that the problem is now known it should be relatively simple to avoid it arising on anything like the same scale in the future.

It's also worth noting that this is just one of the fuselage joins - the one between the cockpit section and the forward fuselage. Most of the rest of the main fuselage is delivered to Everett after being pre-assembled at Charleston (see the very informative video on here) - so possibly the 'good news' is that the rest of the fuselage, and all the other parts, appear to be fitting together without problems?

http://flightblogger.blogspot.com/

Quoting HB88 (Reply 3):
Has anyone covered the pylon/wing interface issue yet?

Yes, HB88 - in fact it was 'covered' in the very article in which it was mentioned. The problem was that insufficient permanent fasteners were fitted in the first batch of components - so you can stop hoping that the pylons don't fit the wings or anything!  Smile:-

".......what I'm told is a delay in attaching the 787 engine pylons to the wings. My source said the delay is the result of about 8,000 temporary fasteners in the wings. The engine pylons can't be attached to the wings until the temporary fasteners are replaced. But the source also said the temporary fasteners are being replaced with permanent ones as they arrive."

http://blog.seattlepi.nwsource.com/aerospace/archives/116545.asp

I don't blame you in the least for watching for, and commenting on, any snags that may appear to be arising in the 787 programme. As you say, you copped - and continue to cop - enough flak over the continuing A380 delays. But please find some new snags soon - there are bound to be plenty, as there are in any new venture on this scale. Please don't keep re-hashing the ones that have already been covered and explained, none of which appear likely to involve anything approaching a 'six-month delay.' And in respect of which, moreover, Boeing have unequivocally stated that no delay is currently expected to the rollout, the first flight, or the first delivery.
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ikramerica
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 11:24 am

Quoting NAV20 (Reply 8):
That would not appear to raise any strength or safety implications, if that's what you're thinking about. Given that the problem is now known it should be relatively simple to avoid it arising on anything like the same scale in the future.

This is quite simple, and yet it is not the "issue" as some had stated. The "issue" was that things weren't being stuffed at Vought. It morphed into a new issue by people who want to keep the thread alive, but this issue is not new either.

Anyway, the thread should be closed and LOCKED because Boeing has come out and answered the rumors with a categorical reaffirmation of their schedule.

Someone is free to open up an "is Boeing lying?" thread, but otherwise, this whole thing is now pointless.

Boeing can not legally make these statements if they know otherwise. Anyone continuing to claim the plane is late is calling the Boeing management criminals, and should understand the implications of claiming people to be criminals without any proof in a public forum...

Mods: close this thread.
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 11:47 am

Quoting Ikramerica (Reply 9):
Someone is free to open up an "is Boeing lying?" thread, but otherwise, this whole thing is now pointless.

Boeing can not legally make these statements if they know otherwise. Anyone continuing to claim the plane is late is calling the Boeing management criminals, and should understand the implications of claiming people to be criminals without any proof in a public forum...

Mods: close this thread.

I tend to agree Irkamerica. Boeing has answered it's critics here on A.net (Yes they do read this stuff too, according to Randy) and has, so far, put to rest rumors of significant delays. Geez people... This is the first 787 being built! There WILL be issues and they will be addressed. Some of the best people, in their respective professions, are involved with this program. If there are some here that are salivating at the prospect of major upheavals in 787 production schedules, then I'm afraid they'll be very disappointed.

[Edited 2007-06-13 04:50:04]
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pygmalion
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 11:51 am

so, hypothetically mind you, suppose the circumferential length of the barrel was dead on. And "Ghost" wanting to move on to the next one, took the first barrel off the alignment "hoop" prior to attaching the frames at the aft end. Again still hypothetically, "Ghost" then set the barrel in a cradle and then fastened the frame to the skin with the barrel deformed under its own weight.... Hmmm.

That might perhaps cause a local deformation that would result in a "bubble" when joined. DA or no DA. Hmmmm. what could one do?... Break that frame loose perhaps? seems possible. Restore the barrel to its normal round contour? Seems likely. So replace the frame attachment to the skin, no mismatch at the joint, all is hunky dory... Just perhaps though, not knowing specifics, rumors might lead someone to jump to horrible conclusions instead of a fairly simple if irritating fix and a missive off to Ghost to never ever rush things again. Hypothetically of course.
 
aminobwana
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 11:51 am

Quoting DLPMMM (Reply 4):
Then shouldn't this thread be moved to Tech-Ops and renamed "787 Barrel Tolerances", as the title of the thread has nothing to do with the subject matter?



Quoting Travelin man (Reply 6):
This quote is further evidence this should be moved to Tech/Ops

I tend to agree with above. May I suggest extend the name to: "Composite Barrel Tolerances and remedies if exceeded" ?

aminobwana
 
mham001
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 12:29 pm

Don't know why they opened another thread about Vought and a rumor after closing the last one, but here's some more information about the interesting problems Boeing is overcoming.

http://blog.seattlepi.nwsource.com/aerospace/archives/116584.asp

James Wallace

"787 fuselage gap was bigger than newspaper photos show....

Initially, my source says, the gap was 1.750 inches."
 
aminobwana
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 4:48 pm

The block states,that:

Quote:
Those photos were taken during the process of fixing the mismatch, after internal structure had been removed from the composite barrels to make them more flexible, and after some hydraulic pressure had been applied

I will not comment this and simply agree with a comment sent to Mr. Wallace by EPSILON, one of his readers (see blog):

Quote:
Dear Mr. Wallace !!

Do you want an answer, even before Mr. Bair tells you so ??

Somebody screwed up !!!

But as you write, this problem affecting the first unit and which certainly will not repeat itself, is already fixed, so why
all the hoopla ? Mistakes anybody makes, the difference between a good management and a bad one is how and whwn they are corrected !!

Epsilon

aminobwana

[Edited 2007-06-13 09:50:05]
 
GBan
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 5:03 pm

Quoting Aminobwana (Reply 14):
I will not comment this and simply agree with a comment sent to Mr. Wallace by EPSILON, one of his readers (see blog):

Am I guessing right that you are EPSILON?
 
DAYflyer
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Wed Jun 13, 2007 10:07 pm

As your previous thread stated, there will be no delays with this program. Good grief, have you nothing else to talk about?
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474218
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 12:17 am

I an totally confused, is it the gap between the two sections of the fuselage they are worried about, or is the mismatch in diameters at a certain point (bulge in fuselage)?

The pictures shows someone holding a rule next to a straight edge showing a mismatch between the the two sections. Then it goes on to describe a gap that you can see the lights in the ceiling through.
 
Beaucaire
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 12:23 am

The issue seems a difference in diamter of the barrels ,indicatded by the different levels of the gauge..
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Beaucaire
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 12:23 am

The issue seems a difference in diameter of the barrels ,indicatded by the different levels of the gauge..
Please respect animals - don't eat them...
 
mham001
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 12:30 am

Quoting 474218 (Reply 17):
I an totally confused, is it the gap between the two sections of the fuselage they are worried about, or is the mismatch in diameters at a certain point (bulge in fuselage)?

Me too. Is it a difference in the total circumference or simply out-of-round?

If a difference in circumference, it is a total screwup and I'd wonder if there is some problem with the shrinkage they get when its baked.

Also, how are these sections connected? I would have thought they overlap but it appears they just butt together. What holds them together?
 
kaneporta1
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 1:07 am

Quoting Mham001 (Reply 20):
Me too. Is it a difference in the total circumference or simply out-of-round?

It seems like one barrel was out of shape. The two sections were joined without any problems on the top, bottom and right hand side, but there was a very obvious gap on the left hand side.
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 1:08 am

Quoting Pygmalion (Reply 11):
so, hypothetically mind you, suppose the circumferential length of the barrel was dead on. And "Ghost" wanting to move on to the next one, took the first barrel off the alignment "hoop" prior to attaching the frames at the aft end. Again still hypothetically, "Ghost" then set the barrel in a cradle and then fastened the frame to the skin with the barrel deformed under its own weight.... Hmmm.

That might perhaps cause a local deformation that would result in a "bubble" when joined. DA or no DA. Hmmmm. what could one do?... Break that frame loose perhaps? seems possible. Restore the barrel to its normal round contour? Seems likely. So replace the frame attachment to the skin, no mismatch at the joint, all is hunky dory... Just perhaps though, not knowing specifics, rumors might lead someone to jump to horrible conclusions instead of a fairly simple if irritating fix and a missive off to Ghost to never ever rush things again. Hypothetically of course.

Knowing what I have read of some of your other posts, and your occasional insight to things Boeing, I am surprised that everyone here has completely ignored your post.

I envsion the whole problem as similar to the "squashed toiletpaper roll" sure in may be out of round but that the nature of a hollow tube and it is easily addressed by pulling/pushing it back into round.

Speaking hypothetically of course.  Smile

Tug
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mham001
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 1:30 am

Quoting Kaneporta1 (Reply 21):
It seems like one barrel was out of shape. The two sections were joined without any problems on the top, bottom and right hand side, but there was a very obvious gap on the left hand side.

Thats what I gathered as well, but wouldn't that imply a difference in total circumference?
 
eatmybologna
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 2:09 am

Quoting Tugger (Reply 22):
I envsion the whole problem as similar to the "squashed toiletpaper roll" sure in may be out of round but that the nature of a hollow tube and it is easily addressed by pulling/pushing it back into round.

O.K. , I understand that the out of round barrel can be manipulated back to a more tolerant round shape with the help of hydraulic jacks, etc. but wouldn't you think that the cured barrel had memory and its shape would return to its out of spec state once the forces were removed?

E-M-B
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Stitch
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 2:13 am

Quoting Eatmybologna (Reply 24):
O.K. , I understand that the out of round barrel can be manipulated back to a more tolerant round shape with the help of hydraulic jacks, etc. but wouldn't you think that the cured barrel had memory and its shape would return to its out of spec state once the forces were removed?

I suppose it could try, but all those fasteners and internal bracing would prevent it from accomplishing that goal.  Smile

This, of course, assumes the CFRP Boeing is using has "memory"...
 
mham001
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2

Thu Jun 14, 2007 2:21 am

But we've been told that 3 sides met the way they were supposed to. Take two rolls of toilet paper, squish one and at least two sides will not match. You cannot have a "bulge" on only one side if the circumference is identical.
Now, to take Boeing at its word that it only required some hydraulic pushing to match up, we have to conclude that the information of the other three sides matching is not true. It would make more sense as I can't see such a colossal mistake as mismatching circumference.
Seems nit picky, I am by no means an engineer, but this "bulge" theory has been bothering me.

[Edited 2007-06-13 19:42:13]
 
eatmybologna
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 2:35 am

So perhaps one way to avoid this problem for future fuselage sections is to surround them each in an outside circumference sleeve prior to, and during assembly of the inner systems (stuffing.) This might prevent the unwanted distortion.
Isn't knowledge more than just the acquisition of information? Shouldn't the acquired information be correct?
 
TeamAmerica
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 2:47 am

Quoting Mham001 (Reply 20):
Is it a difference in the total circumference or simply out-of-round?

Out of round, keeping in mind that the B787 fuselage cross-section is not actually round at all.

Quoting Mham001 (Reply 20):
Also, how are these sections connected? I would have thought they overlap but it appears they just butt together. What holds them together?

A titanium splice plate on the inner surfaces.

Quoting Kaneporta1 (Reply 21):
It seems like one barrel was out of shape. The two sections were joined without any problems on the top, bottom and right hand side, but there was a very obvious gap on the left hand side.

Ah...but was the gap there before they joined the top, bottom and right hand side? See Pygmalion's strictly hypothetical reply #11.  

Quoting Mham001 (Reply 26):
But we've been told that 3 sides met the way they were supposed to. Take two rolls of toilet paper, squish one and at least three sides will not match. You cannot have a "bulge" on only one side if the circumference is identical.
Now, to take Boeing at its word that it only required some hydraulic pushing to match up, we have to conclude that the information of the other three sides matching is not true. It would make more sense as I can't see such a colossal mistake as mismatching circumference.
Seems nit picky, I am by no means an engineer, but this "bulge" theory has been bothering me.

Make a large tube out of relatively thin material. Cut that tube in half - at that instant the two resulting tubes mate perfectly along the cut. Now fasten internal structures into the two tubes, in different places with different crews at different ambient temperatures inserting different parts in different order into each. Bring the two tubes back together and amazingly...they don't mate up! How can this be?

Simple - installing the internal structure introduces stresses into the tube, taking it "out of round". Getting the various sub-assemblies put together such that the result is a perfectly "in spec" shape at the mating surface is a huge challenge - but it is NOT a surprise.

(edit - typo)

[Edited 2007-06-13 19:58:05]
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Stitch
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 2:51 am

Quoting Mham001 (Reply 26):
But we've been told that 3 sides met the way they were supposed to. Take two rolls of toilet paper, squish one and at least two sides will not match. You cannot have a "bulge" on only one side if the circumference is identical. Now, to take Boeing at its word that it only required some hydraulic pushing to match up, we have to conclude that the information of the other three sides matching is not true. It would make more sense as I can't see such a colossal mistake as mismatching circumference.

The gap was more then just along the left-hand side "vertical plane". The right "half" mated properly from the pictures I have seen and the gap was on the left "half" though it did not extend all the way to the crown and belly center-points.
 
bbobbo
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:09 am

Quoting Eatmybologna (Reply 24):
O.K. , I understand that the out of round barrel can be manipulated back to a more tolerant round shape with the help of hydraulic jacks, etc. but wouldn't you think that the cured barrel had memory and its shape would return to its out of spec state once the forces were removed?

But what caused the barrel to go out of spec? Was it cured that way, or did it become that way during finishing, transporting, etc.? If it was cured "in-spec", then there should be no problems. Assuming the CFRP even has memory.

Quoting Eatmybologna (Reply 27):
So perhaps one way to avoid this problem for future fuselage sections is to surround them each in an outside circumference sleeve prior to, and during assembly of the inner systems (stuffing.) This might prevent the unwanted distortion.

And what keeps the sleeve from distorting?  Smile
 
hb88
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2

Thu Jun 14, 2007 3:15 am

Quoting NAV20 (Reply 8):
Quoting HB88 (Reply 3):
"The current discussion was over the significance of the relatively large mating mismatch in the two fuselage barrels and whether it actually mattered or not."

This article gives a pretty fair account of the remedial measures taken which appeared to consist of removing and reinstalling some interior fittings (e.g. floor struts) to achieve a fit.

http://seattletimes.nwsource.com/htm...chnology/2003744076_787gaps12.html

That would not appear to raise any strength or safety implications, if that's what you're thinking about. Given that the problem is now known it should be relatively simple to avoid it arising on anything like the same scale in the future.

It's also worth noting that this is just one of the fuselage joins - the one between the cockpit section and the forward fuselage. Most of the rest of the main fuselage is delivered to Everett after being pre-assembled at Charleston (see the very informative video on here) - so possibly the 'good news' is that the rest of the fuselage, and all the other parts, appear to be fitting together without problems?

http://flightblogger.blogspot.com/

Quoting HB88 (Reply 3):
"Has anyone covered the pylon/wing interface issue yet?"

Yes, HB88 - in fact it was 'covered' in the very article in which it was mentioned. The problem was that insufficient permanent fasteners were fitted in the first batch of components - so you can stop hoping that the pylons don't fit the wings or anything! Smile:-

".......what I'm told is a delay in attaching the 787 engine pylons to the wings. My source said the delay is the result of about 8,000 temporary fasteners in the wings. The engine pylons can't be attached to the wings until the temporary fasteners are replaced. But the source also said the temporary fasteners are being replaced with permanent ones as they arrive."

http://blog.seattlepi.nwsource.com/aerospace/archives/116545.asp

I don't blame you in the least for watching for, and commenting on, any snags that may appear to be arising in the 787 programme. As you say, you copped - and continue to cop - enough flak over the continuing A380 delays. But please find some new snags soon - there are bound to be plenty, as there are in any new venture on this scale. Please don't keep re-hashing the ones that have already been covered and explained, none of which appear likely to involve anything approaching a 'six-month delay.' And in respect of which, moreover, Boeing have unequivocally stated that no delay is currently expected to the rollout, the first flight, or the first delivery.

That's a fairly mean-spirited response there NAV20 and I find your implications about my motivation personally quite, well, disgusting. You don't know me or anything about my involvement with Airbus or the industry.

... "not appear to raise any strength or safety implications, if that's what you're thinking about", "so you can stop hoping that the pylons don't fit the wings or anything", "I don't blame you in the least for watching for, and commenting on, any snags that may appear to be arising in the 787 programme", "don't keep re-hashing the ones that have already been covered and explained".

All provoked by a 3-4 liner? And from memory, I don't actually think I've commented on anything to do with any 6 month delay. So, if you're going to be nasty, try and at least be accurate.

BTW, you also missed the attempt at humour in the pylon/wing comment.

Quoting Ikramerica (Reply 9):
Anyway, the thread should be closed and LOCKED because Boeing has come out and answered the rumors with a categorical reaffirmation of their schedule.

Since when has that been the criteria for suppressing discussion on any manufacturers processes etc? If you don't like the tone or subject matter of this thread, please don't read it. Much easier.

Quoting Ikramerica (Reply 9):
Boeing can not legally make these statements if they know otherwise. Anyone continuing to claim the plane is late is calling the Boeing management criminals, and should understand the implications of claiming people to be criminals without any proof in a public forum...

With respect, that is the most ludicrous pieces of reasoning I have ever seen - although your faith in Boeings candour is touching.

I hope you would not seriously believe that Boeing would issue any public statements what were not worded in ways which would allow them room for legal argument in terms of absolutes and assurances if they were challenged? If they did, they would either have completely incompetent legal counsel or their PR department is out of control.

Whether they are being completely candid or not, you can bet your last dollar that all public statements are vetted for fallback positions in case unknown/undiscovered/hidden issues are in fact there (and just to clarify before you snort coffee out your nose and reach for your keyboard, I am not implying this). Alternatively if in printed form any statement would have the usual disclaimers reciting the standard boilerplate good faith assurances in case they are subject of proceedings at a later date.

I think the experiences of Boeing are extremely interesting given some of the new manufacturing methods they are undertaking. Similarly for Boeing watchers who are Airbus fans, it's very very interesting seeing the project come together - including the ups and the downs.
 
redflyer
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:20 am

Quoting Tugger (Reply 22):
Quoting Pygmalion (Reply 11):
so, hypothetically mind you, suppose the circumferential length of the barrel was dead on. And "Ghost" wanting to move on to the next one, took the first barrel off the alignment "hoop" prior to attaching the frames at the aft end. Again still hypothetically, "Ghost" then set the barrel in a cradle and then fastened the frame to the skin with the barrel deformed under its own weight.... Hmmm.

That might perhaps cause a local deformation that would result in a "bubble" when joined. DA or no DA. Hmmmm. what could one do?... Break that frame loose perhaps? seems possible. Restore the barrel to its normal round contour? Seems likely. So replace the frame attachment to the skin, no mismatch at the joint, all is hunky dory... Just perhaps though, not knowing specifics, rumors might lead someone to jump to horrible conclusions instead of a fairly simple if irritating fix and a missive off to Ghost to never ever rush things again. Hypothetically of course.

Knowing what I have read of some of your other posts, and your occasional insight to things Boeing, I am surprised that everyone here has completely ignored your post.

Perhaps people don't like what Pymalion had to say, since his reasoning may in fact be correct.  

Quoting Eatmybologna (Reply 24):
wouldn't you think that the cured barrel had memory and its shape would return to its out of spec state once the forces were removed?

Maybe the cured barrel was already in an out-of-spec state because of internal support structures and was already under pressure to return to its "memory" state?

Quoting Mham001 (Reply 26):
You cannot have a "bulge" on only one side if the circumference is identical.

Sure you can if your internal support structures are putting pressure on one side or one particular spot. Regardless, if anyone read the entirety of the articles in the Seattle paper or Aero Network, there were several references to traditional aluminum construction encountering the same, if not worse, problems. And those even occur on mature assembly lines.

I think the key to this entire issue, which has come to light only within the past few days, is how quickly Boeing acknowledged the problem and then went on to state unequivocally that roll-out, first flight, and EIS remain on schedule. I can't imagine them making such statements if they in fact were worried about missing deadlines. In the post Enron and A380-delay era, I can't imagine Boeing doing something so stupid and that would open them up to all kinds of much worse problems. (Of course, companies have been known to do even dumber things, but we'll leave that one for another thread.)

[Edited 2007-06-13 20:21:16]
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TeamAmerica
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:23 am

Quoting Eatmybologna (Reply 27):
So perhaps one way to avoid this problem for future fuselage sections is to surround them each in an outside circumference sleeve prior to, and during assembly of the inner systems (stuffing.) This might prevent the unwanted distortion.

Ideally, the internals are installed such that it tends to hold the structure in shape. If you use a sleeve to force the structure into shape, you can introduce stresses that will take the structure out of shape once the sleeve is removed.

Quoting Bbobbo (Reply 30):
But what caused the barrel to go out of spec? Was it cured that way, or did it become that way during finishing, transporting, etc.? If it was cured "in-spec", then there should be no problems. Assuming the CFRP even has memory.

Let's be careful - is there any evidence that either barrel was actually out of spec? May have been, but to me this looks like an issue in assembly procedure which needs to be resolved. The solution to the problem may then be added to the specification, but too soon to say that the subcontractors got it wrong.
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hb88
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:23 am

Quoting RedFlyer (Reply 32):
I think the key to this entire issue, which has come to light only within the past few days, is how quickly Boeing acknowledged the problem and then went on to state unequivocally that roll-out, first flight, and EIS remain on schedule. I can't imagine them making such statements if they in fact were worried about missing deadlines.

My guess is that it might have been because the images of the barrel mismatch were "out in the wild" almost immediately. They had no choice but to respond quickly.
 
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glideslope
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:26 am

Quoting RedFlyer (Reply 32):
I think the key to this entire issue, which has come to light only within the past few days, is how quickly Boeing acknowledged the problem and then went on to state unequivocally that roll-out, first flight, and EIS remain on schedule. I can't imagine them making such statements if they in fact were worried about missing deadlines.

 checkmark  They are not worried. This is what makes Boeing, well, Boeing.
To know your Enemy, you must become your Enemy.” Sun Tzu
 
bbobbo
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:37 am

Quoting TeamAmerica (Reply 33):
Quoting Bbobbo (Reply 30):
But what caused the barrel to go out of spec? Was it cured that way, or did it become that way during finishing, transporting, etc.? If it was cured "in-spec", then there should be no problems. Assuming the CFRP even has memory.

Let's be careful - is there any evidence that either barrel was actually out of spec? May have been, but to me this looks like an issue in assembly procedure which needs to be resolved. The solution to the problem may then be added to the specification, but too soon to say that the subcontractors got it wrong.

Something must have caused the shape to go out-of-spec (whether during curing, transport, assembly, etc.), otherwise the two pieces would have joined with no problems, right? Although maybe out-of-spec isn't the right terminology for a shape distortion.

In terms of the barrel diameter, I agree that there is no evidence that the barrel was out-of-spec.
 
redflyer
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:43 am

Quoting HB88 (Reply 34):
My guess is that it might have been because the images of the barrel mismatch were "out in the wild" almost immediately. They had no choice but to respond quickly.

Respond quickly, yes. To admit quickly the problem occurred, yes. But to reiterate just as quickly that the program schedule remains on track is somehow a sign that they had no choice? On the contrary, the photos had the explosive affect of an expose. Usually, in an expose situation, the victim (meaning the party that was caught with their pants down) will respond with "no-comment"; something along the lines of "we're aware of the problem and we'll have more to say about it at a later date after we've had time to evaluate it"; or they simply come clean and say "yes, we f--ked up and we're trying to understand the impact to the rest of the program", or something to that affect. In Boeing's case, just as quickly as the pictures and news surfaced they just as quickly stated how they fixed the problem and went on to say that the program remains on track.

Now, I will admit that Boeing could very well be lying about this problem (I've always felt their schedule with the 787 was way too ambitious); however, I cannot help but think that it is not as big of a problem as some on here are making it out to be. The reason is because Boeing so quickly came out and stated that the program remains on track -- to do otherwise would create an incredibly huge problem for the company as well as its senior executives. And, secondly, because this kind of problem seems to occur on traditional -- and mature -- production lines. I imagine it is easier to address this kind of problem when working with composite materials as opposed to aluminum materials.
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hb88
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2

Thu Jun 14, 2007 3:47 am

Quoting TeamAmerica (Reply 33):
Ideally, the internals are installed such that it tends to hold the structure in shape. If you use a sleeve to force the structure into shape, you can introduce stresses that will take the structure out of shape once the sleeve is removed.

 checkmark  I think you're right here. One thing which did seem strange is that installing the internal equipping should have revealed the barrels being incorrectly dimensioned as the internal structure would have been built to specific tolerances which assumed specific internal dimensions. Finding this out after installation of some of the internal airframe components is really odd.

Anyway, there are many other things which are more vulnerable to supplier/assembly problems that the barrels. Presumably, the section was mismatched because either the mandrel was out of match or the layup was assymetric. It didn't look like the skin thickness was different around the barrel so it looks like the mandrel was off. If it had deformed under its own weight, I would have thought it would deform symmetrically, not only on one side. I assume they are shipped upright.
 
kaneporta1
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 3:58 am

Quoting TeamAmerica (Reply 28):
Ah...but was the gap there before they joined the top, bottom and right hand side? See Pygmalion's strictly hypothetical reply #11.

That, I don't know, but I assume that at some point there was a very big gap since the two sections were in different continents...

Quoting TeamAmerica (Reply 28):
Make a large tube out of relatively thin material. Cut that tube in half - at that instant the two resulting tubes mate perfectly along the cut. Now fasten internal structures into the two tubes, in different places with different crews at different ambient temperatures inserting different parts in different order into each. Bring the two tubes back together and amazingly...they don't mate up! How can this be?

Simple - installing the internal structure introduces stresses into the tube, taking it "out of round". Getting the various sub-assemblies put together such that the result is a perfectly "in spec" shape at the mating surface is a huge challenge - but it is NOT a surprise.

In this day and age of 3D modeling, determinate assemblies and tolerance allowances that are measured in micrometers, getting a step (not a gap) that's 0.4" only in one place, doesn't make sense.

[Edited 2007-06-13 21:00:11]
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eatmybologna
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 4:01 am

Quoting Bbobbo (Reply 36):
Something must have caused the shape to go out-of-spec (whether during curing, transport, assembly, etc.), otherwise the two pieces would have joined with no problems, right? Although maybe out-of-spec isn't the right terminology for a shape distortion.

In terms of the barrel diameter, I agree that there is no evidence that the barrel was out-of-spec.

True Bbobbo,

The CFRP fuselage, if simply resting in a saddle, could have easily sagged a little from the pull of gravity during the autoclave and normalizing/stress relieving process. I don't recall the image of the autoclave jig, so I apologize in advance if the jig indeed holds the barrel section in a fixed shape.

E-M-B
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srbmod
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RE: 787 May Face 6 Mo. Delay, Vought Involved PT 2.

Thu Jun 14, 2007 4:13 am

Since this thread has gone off-topic like the previous one, it is being locked. This thread was not for talking about the fit issues with barrel sections.

And for those of you wondering why a Part 2 was opened? It was done so at the request of one of the Head Moderators.