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-   -   787 wrinkling composite stops production (https://www.pprune.org/tech-log/385563-787-wrinkling-composite-stops-production.html)

robertbartsch 17th Aug 2009 19:24

787 wrinkling composite stops production
 
Boeing news | Boeing stops work on 787 fuselages made in Italy to fix wrinkled skin | Seattle Times Newspaper


I suppose most have read about this issue earlier and the other delay announced a few weeks ago regarding the wing box defects.

Are these two issues related? The article discusses non-compliant stringers used in the fuse construction and also discusses issues with stringers in the wing box but it also says officials believe these issues are not related.

answer=42 17th Aug 2009 19:58

The article quotes tolerances in "hundreths of an inch".

Can Boeing really still be working in Imperial units for the 787? Or is this journo 'explanation'?

edited to note answer=42 is SLF.

Mr @ Spotty M 17th Aug 2009 21:09

I would say not related, first the wing box is a design problem.
The second is a manufacturing problem with not meeting tolerances in the build.
Think Boeing should have kept the old number 7E7 and not 787, the "E" might mean eventually.:O

Duchess_Driver 17th Aug 2009 21:21


the "E" might mean eventually
Thats why it's been re-named the 'Dream on liner'!

gas path 17th Aug 2009 21:25


Can Boeing really still be working in Imperial units for the 787?
Of course! .....Is there any other 'units' of measurement?:confused:
;)

Kentot Gemuruh 17th Aug 2009 21:26

Dream or nightmare?
 
dreamliner........" dream on liner " ?

scarebus..........nightmare?

robertbartsch 17th Aug 2009 21:31

Obviously, Boeing is an American based company and being that our measures here in the U.S. are Imperial based, ...yeah, we measure in inches, feet, yards, miles, etc. and our temperatures are in Fahrenheit, not centigrade.

As far as I am aware, the meteric system has never been taught in our schools. Apparently, this was an edict from Ronald Reagan.

Max Angle 17th Aug 2009 21:31

You can't help wondering how many fewer 787s Boeing would have sold had they opted for a more conventional airframe construction. My guess is very few, the airlines need new aircraft and a metal 787 would still have been a very efficient machine. I reckon they must be kicking themselves over the decision to go composite, it's going to end up costing them a fortune.

smudgethecat 17th Aug 2009 21:40

FYI answer 42 not only do Boeing use the imperial system but so do Airbus, every nut/ bolt /washer /rivet on their aircraft are imperial, and long may it continue

robertbartsch 18th Aug 2009 13:42

I thought there were too many aircraft in the world today so Boeing and Airbus need to develop inovative technology to encourage airllines to replace their existing fleets. Since the Dreamer is mostly composite, it is 40% (??) lighter than a conventional aluminum plane and, therefore, burns a ton less fuel; right?

Composites have been around a long time and Airbus has used this in VS, and controll surfaces since the 80s. Many beleive these designs or the materials have casues a few tail snapping incidents so far, but the jury is still out, I supose.

Anyway, I guess Boeing will eventually figure this stuff out and make a ton of money in the future.

Graybeard 18th Aug 2009 14:00

It's not like composites are unproven. The DC-3 has fabric covered control surfaces, correct? Wood is the original composite, and plenty of planes were built with that, including my wood-winged 1946 Bellanca Cruisair.

How can aluminum possibly fly? It won't even float!

GB

ChristiaanJ 18th Aug 2009 15:20


Originally Posted by answer=42 (Post 5132050)
The article quotes tolerances in "hundreths of an inch". Can Boeing really still be working in Imperial units for the 787? Or is this a journo 'explanation'?

For linear measurements, it doesn't really matter all that much, since an inch is exactly 25.4 mm.
So for people who have worked all their life with inches, feet and yards, it's easier to visualise 0.04 in, than for me who's always worked with metric, and who had to convert that 0.04 in to 1 mm before it meant something.

Concorde was built using both imperial and metric, and it never really caused any problems. I wouldn't be amazed if most of the Airbus UK workshops (AB wings are nearly all built in the UK) were still using imperial measurements as well.

It's weights and volumes where imperial measurements make less sense to me, because there are no 'clean' conversion factors, and more opportunities for stupid mistaeks.
Ask the pilots of the "Gimli glider", or the Mars probe, that went "splat".

CJ

ChristiaanJ 18th Aug 2009 15:28

Does anybody have a sketch / drawing / schematic, or whatever, of these wrinkles and the associated stringers?

I would have thought stringers etc. would be molded onto the skin panels, like the integrally milled alumininium skin panels of old?

And I doubt Botox is any use?

CJ

Bruce Wayne 18th Aug 2009 15:44

Anyone have any idea how "ramp rash" will be dealt with ?

I did ask a fleet planner of a major that has an order in and was met with a stoney silence!

gas path 18th Aug 2009 17:45


Anyone have any idea how "ramp rash" will be dealt with ?

A metal scab patch...... I believe!
The difficulty will be in spotting the damage in the first place!:suspect:

Spooky 2 18th Aug 2009 22:51

The repair methodlogy has been developed and I know for fact that Boeing has been training maintenance personnel in the process. So the guy with the stoney look on his face must have missed that class.:} I think the biggest concern is detecting ramp rash before it develops into something more serious. Again there is a tool that detects these types of not so obvious dings.

I have been very disapointed in how Boeing has struggled to get this airplane to market but being a little closer to the subject than some, I expect they will work it out..... at what cost, yet to be determined?

subsonic69 19th Aug 2009 05:11

hmm
 
to be honest .. i think boeing will get over these hurdles. lets be real and accept the fact that designing and manufacturing aircraft is not easy. i only have 2 type course and im pretty sure i dont know everything about my types:ouch:. If it was easy .. I would have my own factory by now.:}

late as it may seem. i have to say Boeing will earn a lot from this aircraft. :ok:

FMS82 19th Aug 2009 08:20

787 wrinkling
 
I have a feeling this new wrinkling problem gets a lot of exposure, only because it follows the epic "stringer end cap delamination delay". Obviously it's a big non-conformity, some guys in Italy will have some explaining to do, but I believe this would be normal QA at work to fix the issue.

As Boeing struggles forward they make big leaps in their learning curve and understanding on how to build composite commercial AC. They will reap the benefits; if not on the 787, they will in the single aisle successor some day...

forget 19th Aug 2009 08:52

smudge.

FYI answer 42 not only do Boeing use the imperial system but so do Airbus, every nut/ bolt /washer /rivet on their aircraft are imperial, and long may it continue
Is this true? I hope so! Airbus obviously agrees with Napoleon. :ok:

http://i21.photobucket.com/albums/b270/cumpas/nap.jpg

SLFStuckInTheBack 19th Aug 2009 11:22

Composite v GLARE
 
Sorry if this has been discussed before.....

How does GLARE compare to only composite in relation to weight and ramp rash?


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