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-   -   Eight B787 pulled from service over structural issues (https://www.pprune.org/rumours-news/635106-eight-b787-pulled-service-over-structural-issues.html)

WillowRun 6-3 11th Sep 2020 22:11

Perhaps too much respect attributed to the objective reporting (inquiry, and assessment) by the Dep't of Transportation I.G. about the MAX can lead to exposure to assertions of "quick discounting" or lack of "healthy skepticism" in this nascent situation. An earlier post (#15 - before broad accusatory generalizations surfaced in the thread) didn't claim it was expressing healthy skepticism, but that would be a fair description, looking back.

Still not questioning the overall indictment of how Boeing declined and fell, although that indictment does not make it inadvisable or unnecessary to parse press reports. It could be the case that an inquiry and assessment on a par with the I.G. report (so far) on the MAX debacle would credit the sources and employee reports at face value, but that would be a departure from that method to date. (Of course if it were a choice between needing another I.G. report in another tragic aftermath, or taking those sources at face value, that's an obvious choice.).

etudiant 12th Sep 2020 00:15

Willow Run, you are the voice of reason in many respects on this issue, but honestly, the various testimonies regarding the Max certification as well as the actual evidence of the 737 and 787 assembly deficiencies indicate a truly diseased corporate culture at Boeing. Aerodynamics don't meet spec, time for a 'Jedi mind trick' on the FAA. Stuff does not fit, just make it so. Where did the Boeing integrity go?
There is a great line from the early jet age when CR Smith, the chair of American, asked Donald Douglas for some substantial performance improvement before placing an order. Douglas's response was that 'I can't promise that', to which CR replied, 'I know that, I was just checking to see if you were still honest'.
Boeing too used to be honest, now we are not so sure.

FlightlessParrot 12th Sep 2020 00:41

I don't believe it is strictly thread drift. Although US trades unionism (like so much in the USA) has had more than its fair share of criminality, corruption, and protection of vested interests, the desire to move to a non-union workforce is of a piece with the downgrading of the role of engineers, and the general tendency to treat Boeing as a machine for making money for a few, rather than an organisation for making machines, and making a profit by doing it well. And part of the complexity comes from the use euphemisms, such as "imbalance of power" and "right to work states."

Airbus_A350 12th Sep 2020 00:58

The problem with heavily relying on I.G. reports and the like is that safety regulations are almost always written in blood. Everything is fine until it isn't, and the MCAS saga proves whistleblowers and journalists deserve more credit. The entire point of whistleblower programs is to check otherwise overlooked improprieties.

WillowRun 6-3 12th Sep 2020 01:20

Time for an airport-callsign SLF to enter a plea.

There isn't any question (I've agreed three or four times now (plus a lot of hammering on Boeing on other threads)) that the culture degraded. The point of looking for the niceties of courtroom evidence - since I am copping a plea - apparently doesn't matter in this instance. Maybe there isn't a single assertion in any of the reported deficiencies about these specific manufacturing issues which is inaccurate. I had thought that healthy skepticism works both ways - that to solve the problems Boeing is manifesting, turning the clock back isn't really an option, and so sorting out what's accurate from what may not be accurate actually does matter. But, I cop.

As for euphemisms, perhaps there is knowledge about the Board deliberations and the information upon which they acted in opting to build a plant in South Carolina which makes it clear that the move was thoroughly and exclusively, or nearly exclusively, about avoiding a union workforce. That was not the only factor I recall from decidedly non-inside knowledge of which I was aware. But the label applied to a class of legislation, right-to-work, isn't a euphemism. And by the phrase, imbalance of power, yeah I had hoped to evoke the disdain which a lot of observers have for contemporary progressive dogma. But if the plant relocation was only about avoiding a union and nothing else, then it was an ill-timed shot at sarcasm.

[I'll take: voice of reason. . . when and if I could find it. Thanks.]

Bidule 13th Sep 2020 16:52


Originally Posted by etudiant (Post 10883433)
the various testimonies regarding the Max certification as well as the actual evidence of the 737 and 787 assembly deficiencies indicate a truly diseased corporate culture at Boeing.

And don't forget the 767KCs and rejection of some aircraft at delivery by USAF, for quality issues.

etudiant 13th Sep 2020 17:59

It may be as simple as the logical consequence of manufacturing consolidation. When everyone's livelihood depends on one customer's operations, no one can dare tell that customer that this process is deficient. Anyone who does gets ostracized..
I'm totally certain that lots of people knew about the design weaknesses of the Max, just as they did about the QC failures in the 787. Some heroes tried to sound the alarm, no one wanted to hear it.
In a world where there is one US and one European jetliner manufacturer, who can dare to speak up?

Volume 14th Sep 2020 08:18

The issue is not necessarily quality issues in production.
Whatever part you manufacture, you will have tolerances. It is unavoidable. Especially if you assemble a complex machine from thousands of parts you need to design for tolerances, you need to have provisions in your design to account for them. For example shims.
You need to design for that, you need clear (and workable!) shimming procedures for production. You need to plan for the time it needs to perform this.
The new generation of CAD designers which have never seen production tend to believe that if they specify the dimensions in their computer model to the third digit, it will fit. It won´t !

Composites generally means higher maunfacturing tolerances than metal, and of course in other locations. The wound fusealge barrels of the 787 do not allow any diameter adjustemt, you need to plan for it on the mating parts. If you need to join two non-adjustable parts, you have messed up the design. If you do not realize that from the very beginning and design for it, you will face the issues Boeing does just now. again...

There are reasons, why the A350 fuselage is made from large scale panels, not from seamlessly wound barrels.

Joe_K 14th Sep 2020 09:06


Originally Posted by Volume (Post 10884843)
The issue is not necessarily quality issues in production.

"The manufacturing process uses laser measurement to precisely align the barrel sections and to predict the size of any shims needed. Kowal said the flaw arose when “software notification designed to alert when a shim exceeded the maximum thickness per engineering specifications was not being used.”
From: https://www.seattletimes.com/busines...7-dreamliners/

In my book that's the very definition of a quality issue...

Volume 15th Sep 2020 06:47

Well, obviously somebody in design did not expect that shims beyond a certain thickness may sometimes be required...
It clearly is a quality issue if (to get the job done...) workers in final assembly just force the parts together with shims that are too thin for the tolerances.
But it is a design issue, if you do not correctly predict manufacturing tolerances and don´t plan for them to happen and to be accounted for.

The seamlöessly wound barrel design does not allow to correct the inner diameter in production. It is a nice design with respect to strength, weight and fatigue performance, but a nightmare to deal with tolerances. And if you plan for thick shims, you lose the benefits again...
It was a wrong prediction of manufacturing tolerances that can be met with this type of production. It was lack of composites experience. Partly this is a natural learning curve (after all wound barrels are new), partly it is ignorance not to use the +40 years of experience from glider and small aircraft composites production (which does not exist in the U.S.)

infrequentflyer789 15th Sep 2020 10:51

Joe_K

Not sure that's the right link for the quote, this one definitely has it: https://www.seattletimes.com/busines...may-be-needed/

And yes, it is the very definition of a quality issue in my book. It isn't really a design issue if the designers had specified that this software should have been used, any more than it is a design issue if a part is not made to specified tolerance. This sort of thing may be a design issue (failure to design for production) if, say, tolerances are too tight to be produced with the machinery available or the operator skills available etc. but "was not being used" doesn't indicate that, rather it indicates failure to follow specified process. This is why having loads of "tried and tested processes" (see MAX threads) is no defence (or at least not a complete one) - processes and procedures are no good if they are not followed. Like, say, designing and specifying a component to be made to certain tolerances on a CNC machine, then not bothering with the CNC and just machining it by hand - not that anyone would ever do that in aircraft manufacturing of course.

The really big question is why the software / process "was not being used" - someone just forgot (at least eight times?), or someone wasn't trained properly, or someone was told (or pressured) not to use it in order to speed up production...

GlobalNav 15th Sep 2020 17:18

Or the software was impractical in the production environment. Who knows?

etudiant 15th Sep 2020 19:06

Very likely true.
Manufacturing by remote control from the HQ often generates this kind of disconnects. The testimony of the Boeing 737 Max executives underlines that. (
They are certain the design process worked splendidly, even after the casualties were in the hundreds and the costs in the billions.

tdracer 15th Sep 2020 19:43

I had plenty of first hand experience dealing with various Boeing process software programs. To say they weren't user friendly would be a massive understatement.

megan 16th Sep 2020 02:03


after all wound barrels are new
The first Beech Starship (1986) had a carbon fibre wound over a mandrel fuselage, as did the Premier IA (1998) and Hawker 4000 (2001), so the technology has been around for a while, if not to the scale of the 787. A bit of an article.

https://www.intechopen.com/books/aer...ng-perspective


SLF3 16th Sep 2020 09:25

If the issue is the flatness of the sealing face, and the tolerance is 0.005", how do you inspect without disassembling the joint?

CW247 16th Sep 2020 19:02

Very well written article that stitches it (pardon the pun) altogether nicely:

https://seekingalpha.com/article/437...ring-nightmare

Running Ridges 16th Sep 2020 21:02

SLF3

Ultrasound NDT methods would probably pick up the gaps created by the waviness of the surface

TLoraine 6th Oct 2020 18:56

Boeing are said to be closing their 787 production line at Everett so everything will be built in SC. Is that where Al Jazerra filmed their investigative documentary about alleged quality control issues on the 787?

joe_bloggs 6th Oct 2020 20:18

That is correct.


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