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Door blows out during ground test on Boeing 777X jet

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Door blows out during ground test on Boeing 777X jet

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Old 28th Nov 2019, 23:46
  #141 (permalink)  
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The reality of delegated authority is that the FAA picks and chooses what is delegated and what it retained, whatever you might think of it in your reality.
Delegation allows the authority to provide a service with more efficient use of authority staff time. If there were no delegation, the taxpayer would be covering the cost of hundreds more staff, both for the volume of certification work, and the in depth knowledge of certain disciplines.

Oh, by the way, 'ever had a pilot flight test? Was it administered by a staff pilot of the authority? Or a delegated examiner? C of A's issued to aircraft - most commonly by a delegate, rather than an authority staff member.

I always invite the authority to witness certification tests I carry out, even if the test is entirely delegated to me. Doing so affords the authority the opportunity to learn, while witnessing testing they otherwise probably could not see first hand. In co witnessing testing, the standards for the test and acceptance, and agreement as to how to disposition unexpected outcomes becomes a joint task, rather than just the delegate - 'builds confidence in the certification system.

Delegation is not perfect, but it's necessary, or our industry would grind to a slow pace.
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Old 28th Nov 2019, 23:48
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rem fdr " Oh Grebe, the first 767 - VA001 - was not sold to United. It was initially kept by Boeing for use as a flying test bed, before being modified to the AOA (Airborne Optical Adjunct) test aircraft as part of Reagan's 'Star Wars' initiative. "

My confusion/memory re VA001 came from an event in about 1992- . I had kept a copy of the 767 firing order published in 1982 or so, and had dug it out as part of my 1992-93 deposition on some specific tooling and patent issues. AS I recall ( but could be wrong ) the firing order showed VA001 as being ***assigned *** to UAL. The assembly dates were critical, specifically when the tool was first used on a part of the 767 ' production' aircraft versus when the firm that had patented the tool and claimed a design and manufacturing date of the tool as being about 6 months later. Eventually they lost the patent because I was able to show via records accurate to within a few M days the tool setup dates, load dates, etc . I have since thrown away virtually all my notes and depositions. So based on my memory I ** assumed** that UAL had eventually taken delivery. I left the 767 program in 1983 for what was known as WILO and came back to everett on the 777 program about 1993 or so.

MY goof - my point was that that the static test and fatigue test airplanes ( at least at boeing ) are not planned to be put in flyaway condition other than basic structure- and not sold except for scrap or cutaways or whatever.

And FWIW the times article mentioned the loading on the fuselaghe as xx thousand lbs bending downward. Since the it was not pulled down while sitting on the landing gear, a simple force diagram would show that since plane was not moving up or down, somewhere the equal and opposite load up ward had to be available - that upward load was of course the wings bending upward by pulling on a bunch of cables etc

Last edited by Grebe; 28th Nov 2019 at 23:59. Reason: clarificatin my goof re 767 and
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Old 29th Nov 2019, 02:06
  #143 (permalink)  
 
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Originally Posted by Grebe
My confusion/memory re VA001 came from an event in about 1992- . I had kept a copy of the 767 firing order published in 1982 or so, and had dug it out as part of my 1992-93 deposition on some specific tooling and patent issues. AS I recall ( but could be wrong ) the firing order showed VA001 as being ***assigned *** to UAL. The assembly dates were critical, specifically when the tool was first used on a part of the 767 ' production' aircraft versus when the firm that had patented the tool and claimed a design and manufacturing date of the tool as being about 6 months later. Eventually they lost the patent because I was able to show via records accurate to within a few M days the tool setup dates, load dates, etc . I have since thrown away virtually all my notes and depositions. So based on my memory I ** assumed** that UAL had eventually taken delivery. I left the 767 program in 1983 for what was known as WILO and came back to everett on the 777 program about 1993 or so.
VA001 was originally intended to go to UAL as you note, but there were some issues with the way it was built that made it unsuitable for commercial service, so Boeing held on to it. Then again, the general view is that Boeing made far more money leasing it to the USAF as the AOA test bed than they would after doing a post-flight test refurbe and delivering it to United.

Regarding the Seattle Times article, I almost laughed when I saw the part about "The test plane is a complete write-off". As if that airframe was ever going to used for much of anything else after the ultimate load test
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Old 29th Nov 2019, 02:21
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Originally Posted by tdracer

Regarding the Seattle Times article, I almost laughed when I saw the part about "The test plane is a complete write-off". As if that airframe was ever going to used for much of anything else after the ultimate load test
td,
If it had not failed, it could have been used for other tests, couldn't it ?
Also they were meaning it was destroyed ?
With respect :
Knowledgeable people laugh when journalists use simplified terms for the layman to get the picture.
More knowledgeable people don't laugh nor fuss : they are capable of adapting their level of language to any public.

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Old 29th Nov 2019, 02:36
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fly aiprt said ' If it had not failed, it could have been used for other tests, couldn't it ?
Also they were meaning it was destroyed ?"

even with the failure as described, other smaller tests on certain parts may be done. Other uses can also include minor changes in part configuration found as part of fatigue tests. For but one very old example. The 767 static test failed a bit below the 1.5 mark due to a stringer problem near the tail. So it was removed and parked outside. A year or so later, when some data analysis showed a stress problem with a few fasteners near the aft side of the wing box, the solution was to simply remove the fasteners and cut a " flange" part about 2 inches shorter.By that time a half dozen or more planes had been assembled. In order to determine what special tool might be needed, I simply got permission from engineering to take a mechanic out to the plane, cut off a few collars on the fasteners, and use a small cutoff saw to trim as needed. Then simply write up the process, location, tools needed such that the shop could follow thru on planes that were past that point in assembly. Just but one example of possible use of a failed static test unit.

I'm sure there are many other examples of ' use' of failed static test parts/planes

Last edited by Grebe; 29th Nov 2019 at 02:40. Reason: fat fingers
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Old 29th Nov 2019, 02:40
  #146 (permalink)  
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If it had not failed, it could have been used for other tests, couldn't it ?
Test articles are subject to "conformity inspections" prior to acceptance for test. It may be the case that a previously tested part is used for a subsequent test, though such reuse would be describe and agreed in the test plan, and the test article would have to be inspected to assure that it was "test worthy" which would equate to airworthy - no defects. Deviations can be allowed, where they would not affect the outcome of the test. It is not in the applicant's interest to test a defective test article, as the test could be a false fail.

Where the test is a flight test, obviously, we intend that the aircraft is returned at least reusable, if not still certifiable. Examples would include over speed or over weight testing in flight, where an inspection of the aircraft following test should verify that the aircraft remains airworthy. Manufacturer's test prototype aircraft are rarely released into service, often because they don't exactly represent the final approved design anyway.

There are times when I'll plan a test to demonstrate compliance to the requirement, then the requirement plus a factor of safety (which may deform and ruin the test article), and then following removal of the test load, a test to destruction, to see how it failed, rather than at what load it failed.
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Old 29th Nov 2019, 02:46
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Originally Posted by Fly Aiprt
td,
If it had not failed, it could have been used for other tests, couldn't it ?
Also they were meaning it was destroyed ?
The ultimate load test is always the last planned test for that airframe, since it is often tested to destruction during that test. Further, even if it doesn't fail, the test will take portions of the airframe beyond the plastic deformation stage, so its value for any additional testing is minimal. When they did the 767 ultimate load test ~40 years ago, they planned to test the wings to destruction, but the fuselage failed first.
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Old 29th Nov 2019, 05:38
  #148 (permalink)  
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Originally Posted by tdracer
The regulations spell out the minimum requirements - it's always acceptable to do cert tests that exceed those minimum requirements.


The reality of delegated authority is that the FAA picks and chooses what is delegated and what it retained, whatever you might think of it in your reality.

The level of ignorance of certification requirements, testing, and procedures exhibited by some of the critics on this forum is rather disturbing.
With respect:
This is a mainly a pilots forum and not so much an "engineering" forum. Your quote relating to the "level of ignorance of certification requirements" may have been construed to mean "engineers have no idea how critical pilots deal with required certifications during line operations", so this may also be true that engineers are also "a disturbing ignorance" to line pilots in general. Pilots fly, engineers do what they do!
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Old 29th Nov 2019, 05:57
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Originally Posted by Fly Aiprt
td,
If it had not failed, it could have been used for other tests, couldn't it ?
Also they were meaning it was destroyed ?
With respect :
Knowledgeable people laugh when journalists use simplified terms for the layman to get the picture.
More knowledgeable people don't laugh nor fuss : they are capable of adapting their level of language to any public.
As you know, knowledge is wisdom.
“The only true wisdom is in knowing you know nothing.”
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Old 29th Nov 2019, 06:00
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Originally Posted by 568
With respect:
This is a mainly a pilots forum and not so much an "engineering" forum. Your quote relating to the "level of ignorance of certification requirements" may have been construed to mean "engineers have no idea how critical pilots deal with required certifications during line operations", so this may also be true that engineers are also "a disturbing ignorance" to line pilots in general. Pilots fly, engineers do what they do!
Yes, the engineers are by and large somewhat ignorant of what pilots do. However for the most part we know better than to go on a public form and overtly criticize what the pilots are doing based on that ignorance. Many posters - alleged pilots, although in some cases I have my doubts - on this form have no such qualms regarding what the engineers do.
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Old 29th Nov 2019, 06:07
  #151 (permalink)  
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Originally Posted by tdracer
Yes, the engineers are by and large somewhat ignorant of what pilots do. However for the most part we know better than to go on a public form and overtly criticize what the pilots are doing based on that ignorance. Many posters - alleged pilots, although in some cases I have my doubts - on this form have no such qualms regarding what the engineers do.
Indeed that may be true, but I can attest that the converse is also true, outside of public forums.Happy Thanksgiving BTW.
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Old 29th Nov 2019, 12:06
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At the same time, the fuselage was bent downward at the extreme front and aft ends with millions of pounds of force. And the interior of the plane was pressurized beyond normal levels to about 10 pounds per square inch — not typically a requirement for this test, but something Boeing chose to do.
In other words, Boeing had previously done the 1.5x pressurization test - and passed. Then, although it's not a regulatory requirement, they again pressurized the fuselage to 1.5x when they did the wing ultimate load test - when it failed at 99% of target.
I believe this is where the theories come from...overpressure the hull to prevent buckling...
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Old 29th Nov 2019, 21:23
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Quote:
Originally Posted by OldnGrounded OK, but that doesn't actually say anything, at all, about the reality of delegated certification authority, which is an undeniable, inarguable reality -- whatever you think of it.
Originally Posted by tdracer
The reality of delegated authority is that the FAA picks and chooses what is delegated and what it retained, whatever you might think of it in your reality.
Umm . . . I'm not sure how you understood what I wrote to suggest otherwise, but . . . it did not and I do not. I simply said that the fact that FAA personnel were present at the referenced test doesn't mean or indicate anything about delegation to the manufacturer. And it doesn't.

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Old 29th Nov 2019, 22:53
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Originally Posted by OldnGrounded
Umm . . . I'm not sure how you understood what I wrote to suggest otherwise, but . . . it did not and I do not. I simply said that the fact that FAA personnel were present at the referenced test doesn't mean or indicate anything about delegation to the manufacturer. And it doesn't.
Yes, it does. The FAA can choose to witness any cert test they want - even if the test has been delegated. Once the FAA chooses to witness the test, the FAA assumes the responsibility for the acceptability of the test and test results (e.g. pass/fail). Quite common in flight testing - the FAA will often decide they want to ride along to observe even if the test is delegated - once they do that they effectively override the ARs (delegated equivalent of a DER) in determining the acceptability of the testing and the results. And yes, it often goes the other way as well - the FAA retains a flight test, but for some reason decide not to go along on the flight test - automatically delegating the authority to the Boeing ARs witnessing the test.

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Old 30th Nov 2019, 10:24
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Originally Posted by tdracer
Yes, it does. The FAA can choose to witness any cert test they want - even if the test has been delegated. Once the FAA chooses to witness the test, the FAA assumes the responsibility for the acceptability of the test and test results (e.g. pass/fail). Quite common in flight testing - the FAA will often decide they want to ride along to observe even if the test is delegated - once they do that they effectively override the ARs (delegated equivalent of a DER) in determining the acceptability of the testing and the results. And yes, it often goes the other way as well - the FAA retains a flight test, but for some reason decide not to go along on the flight test - automatically delegating the authority to the Boeing ARs witnessing the test.
I'm definitely not making myself sufficiently clear. I understand (really!) about the individual test. I was trying to make the point that what happened at that moment in time isn't particularly relevant to the overall question of delegation.

But we're just arguing past each other, so let's stop.
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Old 1st Dec 2019, 08:09
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May I ask a question about delegation, relevant to anyone who may travel on a Boeing aircraft.

I have formed the notion, from this discussion, that in the good old days the FAA delegated a lot of responsibility to individual Boeing engineers, who reported to the FAA; the engineers had to manage their dual loyalties, but the FAA was in a position to check that. I think that what has happened is that the engineers now report to Boeing managers, which means that the FAA has delegated responsibility not to engineers whom it can choose, but to the Boeing company.

Is this notion accurate? If so, it's troubling, because individuals have ethical standards, but by modern doctrine, a company's responsibility is to its shareholders, not any ethical ideals.
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Old 1st Dec 2019, 09:29
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Very well summed up!
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Old 1st Dec 2019, 15:51
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Originally Posted by FlightlessParrot
May I ask a question about delegation, relevant to anyone who may travel on a Boeing aircraft.

I have formed the notion, from this discussion, that in the good old days the FAA delegated a lot of responsibility to individual Boeing engineers, who reported to the FAA; the engineers had to manage their dual loyalties, but the FAA was in a position to check that. I think that what has happened is that the engineers now report to Boeing managers, which means that the FAA has delegated responsibility not to engineers whom it can choose, but to the Boeing company.

Is this notion accurate? If so, it's troubling, because individuals have ethical standards, but by modern doctrine, a company's responsibility is to its shareholders, not any ethical ideals.
The delegates always report to their company managers but are still responsible to the FAA for their decisions. No way can a company manager over-rule the delegate. The company delegate does his job of informing his company manager of his interfacing responsibilities with the FAA.

In my view if there was a fault, it was in the decision making based on the information provided to the delegate/FAA and not the chain of command nor a mixed allegiance
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Old 1st Dec 2019, 16:29
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To refine lomapaseo's post a little, the FAA delegates an organizational delegation to the applicant company (Boeing, in this case), who then nominates individuals employed by the company to be delegated persons. The FAA would accept each person to hold a delegation, based upon their merits, and hold that [each] person directly responsible to the FAA. And, the FAA would hold the delegated company also responsible for the overall management of the company's delegation.

In the case of a small problem, the FAA could elect to increase oversight of the delegated work. Surveillance is an FAA responsibility, and its depth and frequency are based upon risk analysis done solely by the FAA. A greater problem could be addressed by reviewing the delegation of the individual, or the company delegation as a whole. For my experience, a delegation holder acts rapidly, and definitively to accept the FAA's desired oversight to prevent the FAA considering removing delegation.

It is a dual loyalty situation, where the delegated person is employed by, and paid by the company, which discharging their their responsibility to the FAA. This is a part fo the reason that the company also holds organizational delegation, so they have something to loose if they appear to influence the work of the delegated person(s).

This is a necessary system, otherwise the FAA would have to employ hundreds more highly qulified people in the certification role, and certification would slow down. It's just a matter of finding the balance of delegation and oversight.
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Old 1st Dec 2019, 18:56
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Hopefully I have engaged my brain now.

So this *was* the ultimate load test, and the airframe gave way at 99% — in what must be a fairly unusual way? Is the object of this test to test the wings alone or the fuselage and wings as a unit? My introduction to the test was the 777 documentary way back and I’ve always assumed only the wings were being tested.

It must be a safe bet that Boeing didn’t expect the fuselage to fail, but is it possible that the failure is an artefact of the test?
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