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Brian Abraham
23rd Sep 2011, 02:24
From AVwebFlash Complete Issue (http://www.avweb.com/eletter/archives/avflash/2012-full.html#205410)

One reason we don't know more about why Boeing aircraft suffered fuselage skin cracking can be tied to regulatory decisions made by the FAA. A Southwest Airlines 737-300 suffered a crack in its fuselage on April 1, and an American Airlines 757-200 suffered a tear in its skin last year. Both incidents led to the discovery of symptoms that could lead to similar problems on other jets. In the case of the 737, rivet work was questioned. In the case of the 757 the NTSB determined that the aircraft's skin was of nonconforming thickness -- it was thinner than it was supposed to be. But Boeing's records of how those and other affected planes were built and inspected were missing ... as directed by the FAA.

A study of the manufacturing processes for the jets could explain why or how each situation came to pass. Without the associated paper trail, such a study is not possible. In 2009, the FAA revised rules previously devised in 1964 that set limits for how long manufacturers should keep records of their manufacturing and inspection processes. Per the old rule, manufacturers records should be kept for two years. The new rule requires that record are kept for five years and 10 years in the case of critical components. Southwest's jet, which saw a 5-foot section of the fuselage tear open at 34,000 feet, was built in 1996, so Boeing kept no records. The American Airlines jet entered service in 1990 so, again, no records are available. The NTSB found that "incorrect manufacturing" led to the problem on the 757. And thanks at least in part to the FAA's 5-year rule, there were limits on what else the bureau could find. "Therefore," said the NTSB, "a cause for the manufacturing non-conformance could not be identified."

DCA11FA004 (http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20101027X04916&key=1)

fdr
23rd Sep 2011, 03:48
Once upon a time I would agree with your assessment, however I would think that recent events, since the termination of QA auditors who were identifying non compliant (and I think I am being very generous in terminology) fabrication of the fuselage barrels of the B737NG's and the abject underwhelming response of the FAA, highlights the fact that both Boeing and FAA are at best resting on their laurels.

On August 21, 2006, Sky News alleged that Boeing's Next Generation 737s built from 1994 to 2002 contained defective parts. The report stated that various parts of the airframe produced by Ducommun were found to be defective by Boeing employees but that Boeing refused to take action. Boeing said that the allegations were "without merit".[9] However, a one year investigation by Al Jazeera's People & Power series in 2010 questions the safety of some structural parts in 737s.[10]

[/URL]

[url]http://www.youtube.com/aljazeeraenglish#p/u/0/KFUFFzkCQXw (http://www.upi.com/Top_News/2006/08/21/Report-alleges-faulty-parts-in-jets/UPI-75931156177507/)

Are Boeing's Big Jets Safe? [Archive] - PPRuNe Forums (http://www.pprune.org/archive/index.php/t-195565.html)

FindACase™ | United States ex rel Smith v. Boeing Co. (http://ks.findacase.com/research/wfrmDocViewer.aspx/xq/fac.20080806_0000400.DKS.htm/qx)

FindACase™ | United States ex rel Smith v. Boeing Co. (http://ks.findacase.com/research/wfrmDocViewer.aspx/xq/fac.20100401_0000209.DKS.htm/qx)


Flight Risk | Mother Jones (http://motherjones.com/politics/2005/11/flight-risk)

On a wing and a prayer - People & Power - Al Jazeera English (http://english.aljazeera.net/programmes/peopleandpower/2010/12/20101214104637901849.html)

http://www.hamilton-co.org/appealscourt/docs/decisions/C-070330_04022008.pdf

Contractor Case - Federal Contractor Misconduct Database - POGO (http://www.contractormisconduct.org/index.cfm/1,73,222,html?CaseID=294)

Flight Risk - Mother Jones - Nbr. 306 - Author: Kaplan, Sheila - Id 62717043 - vLex (http://news-business.vlex.com/vid/flight-risk-62717043)

Internal Boeing Documents Support Whistleblower's Allegations: Aircraft Quality Control Problems Cited (http://www.pogo.org/pogo-files/alerts/transportation/tr-faa-20080508.html)

http://pogoarchives.org/m/tr/faa-boeing-audit-20000211.pdf

DoD IG Report on Audit of Boeing Spare Parts Contracts (May 2011) (http://www.pogo.org/resources/national-security/dod-ig-report-on-audit-of-boeing-spare-parts-contracts.html)

Boeing asks for media contacts from former workers in whistle-blower case / LJWorld.com (http://www2.ljworld.com/news/2010/oct/16/boeing-asks-media-contacts-former-workers-whistle-/)

USA is hardly the poster child for jurisprudence... even with the greatest sympathy for 9/11

Golden Rivit
23rd Sep 2011, 04:56
The Last Inspector - Boeing Fraud & FAA Fraud Risking Safety (http://www.thelastinspector.com/index.html)

PAXboy
23rd Sep 2011, 13:59
I have just read the link provided by GR. Fascinating but none of this is a surprise. Any mature company/organisation will be liable to this kind of behaviour (not all will succumb, of course) but since mankind has decided that the accumulation of wealth is paramount, then people will move towards it.

This article is a fascinating example of The Normalisation of Deviance. (many examples can be searched for). Can this corruption be stopped? Yes - but only when enough people have died and it can be PROVED to be caused by the corruption.

Lyman
23rd Sep 2011, 17:33
Not entirely true. There are ways to short circuit this malevolence that haven't to do with deaths per mile.

To think our Congress will have any success is laughable. Henry Waxman?
He is a bag man for the people he purports to keep in line. What a laugh.

The loss of innocence will be the first and most necessary step. That and the rejection of Apathy.

Without consequence, there is no progress, and without risk, there is real danger.

EEngr
25th Sep 2011, 16:12
Is this 'Pick on Boeing' week?:uhoh:

I just saw another thread, possibly about 747 electrical systems: http://www.pprune.org/tech-log/464584-bbc-electricity-series.html#post6716841

I'm not certain I want to go after the company. But if we're piling on the FAA (or Congress), count me in. Companies have a duty to their shareholders to push their policies and procedures right up to the limit of the law in order to maximize profitability. Its up to the regulatory agencies to maintain vigilance and not succumb to 'regulatory capture'.

Lyman
25th Sep 2011, 16:37
Focus is focus, and there's plenty to go around re: procedural whip.

It takes two, and to say that only one side is motivated is not accurate.

Boeing has a more direct, and quantifiable, goal.

The regulator, not so much, it is more reliant on "Protected Duty", and succumbs more easily to pressure, since push back is easily "managed".

Profit trumps Public Duty when it comes to "Mission".

Why doesn't Boeing test the 787 for flame toxics?

Turbine D
25th Sep 2011, 21:39
Lyman

Why doesn't Boeing test the 787 for flame toxics?

Perhaps Boeing has, but if they didn't others have. Here is an FAA report on the subject. Also, don't forget Airbus is not far behind on the use of composites for fuselages.

http://www.tc.faa.gov/its/worldpac/techrpt/ar98-34.pdf

Regards,

TD

DozyWannabe
25th Sep 2011, 22:19
@Turbine D

I don't think this as an A vs. B thing - such trends (regarding disbonding in 737s and things of that nature) are to be monitored in all manufacturers.

Maybe I'm getting a bit cantankerous myself - I know how clever today's aeronautical engineers are, but a small part of me will always be a little nervous that I never saw a 787 fuselage in a big water tank ala the Comet 1.

Turbine D
25th Sep 2011, 23:12
Dozy

I was not making an Airbus vs Boeing thing as you might think. I was just saying the technology for the use of composites for modern day commercial aircraft is here.

If you are concerned about pressure testing of the Boeing 787 fuselage, rest assured it was accomplished. I am not sure today's technology requires the use of water tank submergence as was the case of the Comet years ago. However, here was the results of Boeing's testing on the 787:

On March 28, 2010 loads were applied to the test unit to replicate 150% of the most extreme forces the airplane is ever expected to experience while in service, Boeing claimed. The wings were flexed upward by approximately 25 feet (7.6 meters) during the test and the fuselage was pressurized to 150% of its maximum normal operating condition.

In evaluating the success criteria for the test, Boeing said that its specialists have been poring over the thousands of data points collected during the test to ensure that all parts of the airplane performed as expected.

Regards,

TD

HarryMann
25th Sep 2011, 23:29
to 150% of its maximum normal operating condition.

to 150% of its maximum service operating condition ?

DozyWannabe
25th Sep 2011, 23:42
@Turbine D

It's not the occasional high-load stresses that bother me as much as the research into pressurisation cycles over time. When we went to jets made from aluminium, it turned out that we didn't know as much about how fatigue affects an aluminium pressure vessel as we thought. Hopefully the bods at all the manufacturers have got it right this time!

(That said, the Achilles' heel of the Comet 1 turned out to be fatigue cracks emanating from rivet holes aruond the windows - the 787 doesn't use rivets in the traditional sense)

Starter Crew
25th Sep 2011, 23:57
Hi, Dozy.

I drive past this (http://787flighttest.com/testing-begins-on-fatigue-airframe/) every time I have to work up in the Everett plant - the fatigue test airframe that they encased in its large blue "exoskeleton" late last year. The rig is designed to push the plane through (hundreds of) thousands of taxi, takeoff, flight, landing, taxi cycles - and over a range of flight profiles.

The flight cycles include pressurization according to the "flight" profiles, so as well as the usual spider web of jacks/pulleys/weights, the rig incorporates the capability to pump up the fuselage.

Can't find the reference quickly here on a sunny Sunday, but there's a published number of flight cycles that had to be achieved before entry into service, and the fatigue airframe has to maintain a substantial "lead" over the highest in-service item.

EVERETT, Wash., Sept. 13 — Boeing has begun fatigue testing on the structural airframe of the 787 Dreamliner at the Everett, Wash., site. Fatigue testing involves placing the 787 test airframe into a test rig that simulates multiple lifecycles to test how the airplane responds over time. (http://787flighttest.com/testing-begins-on-fatigue-airframe/)

DozyWannabe
26th Sep 2011, 00:11
Cheers - thats reassuring! :)

EEngr
26th Sep 2011, 01:42
It certainly is ... for that fuselage.

Now, if only there were some way of ensuring that subsequent production articles are all produced per the certified design. And that QA data was tracked for subsequent production units (or a statistically significant group) to ensure detection of trends deviating from the original production tolerances. And that this data was kept in the event unforeseen in service quality issues arose, making it possible to trace back and correct manufacturing problems.

One can dream, I suppose.

italia458
26th Sep 2011, 03:12
Also, don't forget Airbus is not far behind on the use of composites for fuselages.

Not far behind?! The A350, according to Wikipedia, has a higher percentage of composite components than the B787, 53% vs 50%.

And having a quick read over this (http://www.tc.faa.gov/its/worldpac/techrpt/ar98-34.pdf) doesn't make me feel great!

EEngr
26th Sep 2011, 15:38
When my aircraft's fuselage bursts into flames, the health hazards of the combustion products are down my list of priorities a few notches.

I'd like the power system protection to trip an arcing buss off line rather than burn a hole in the skin, for example.

Lyman
26th Sep 2011, 17:38
Strikes me that has happened, and involved both of your serious concerns. In assignerd order of priority, at that.

3holelover
26th Sep 2011, 21:05
Are they also considering, or adding, the effects of unreported ramp rash and hangar rash? There WILL be occurrences of both, guaranteed, so how will these untold bits of minor damage to the pressurized carbon fibre hull figure in on the test equations? ...if at all? ...and if not, I do sincerely hope every little ding is either very easily spotted, or of no consequence.

amicus
26th Sep 2011, 21:47
The fact of the matter is that, normally, in a survivable crash fire scenario a la A340 AF survivable crash in Malton and well over a hundred others, that the fuselage cracks or fractures allowing ingress of toxic gases into the cabin. This has never been tested on 787 despite a series of industry inputs stressing the vital necessity of such testing given the flammability and FST characteristics of epoxy composites.
So now it seems that in-service issues and experiences will either validate or obviate such fire, smoke and toxicity concerns. And only time will tell and I am not optimistic of the outcome.

Lyman
26th Sep 2011, 22:16
Perhaps it was seen as too large a gamble, to test the structure for flame products invasion.

On to 'flight test' then.

westhawk
27th Sep 2011, 00:24
Are they also considering, or adding, the effects of unreported ramp rash and hangar rash?

Presumably all part 25 aircraft must meet the in service damage tolerance requirements outlined in 25.571 (http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=ca46c5d92a3c9e3231e56f68d85a205d&rgn=div8&view=text&node=14:1.0.1.3.11.3.170.65&idno=14). The specific methodology to be used to perform these evaluations is not detailed in the regulation. I would expect that test and evaluation methodology guidelines exist in other documents and new ones are developed and approved as needed.

Time will tell how well any airliner type tolerates the abuse of day to day service and whether or not established inspection methods and intervals are sufficient to prevent critical failures. Past experience demonstrates that the prevention and detection of such damage greatly depends upon the level of care and diligence practiced by the individual airline. With that being the case, I fully expect that it's only a matter of time before a severely impact damaged 787 is inadvertently taken into the air to test the efficacy of the damage tolerance testing and evaluation required to become certificated. It's happened with most types to date!

Will baggage carts and belt loaders stop smashing into airliners at the gate? Will ill-trained ground handlers with no investment or background in aviation recognize the need to report incidents to qualified personnel when the inevitable accidents occur? The answer to both questions is obvious. Ground damage will occur. Some instances will then go undetected and/or unreported. Time will tell as to whether the consequences of those events will be any different than they have been with aluminum airliners up to today. It could go either way.

Turbine D
27th Sep 2011, 02:46
Lyman

Perhaps it was seen as too large a gamble, to test the structure for flame products invasion.

Here is some work done to look at flammability on Boeing's composite material.

http://www.fire.tc.faa.gov/pdf/07-57.pdf

TD

Flapping_Madly
27th Sep 2011, 20:33
Just curious--not trying to stir any pot.
Does that Boeing test rig include freezing the airframe to minus 60 and baking it to plus 50 a few times a day?

Couldn't see anything.

Just curious. Thank you.

Starter Crew
1st Oct 2011, 02:14
Does that Boeing test rig include freezing the airframe to minus 60 and baking it to plus 50 a few times a day?

No, the entire structure resides outdoors at Everett, so operates within the normal meteorological conditions for that location. I don't know for sure, but I think there are a number of small cold-soak and/or baking chambers where examples of critical structure are cycled.

I will check around.