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  • Originally posted by Evan View Post

    Aha. Was that a mid-level improv move or a top level design move, I wonder. Was it coming from the pocket protectors in engineering (why?) or was it, "hey Barney, we're out of rivets... Yeah, yeah, just use screws, time's a wastin'"?

    How much substitution is allowed within the limits of certification?
    This from the Keyboard Captain.

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    • Originally posted by Evan View Post
      Culture.
      CNN is reporting that Boeing senior management stated as recently as last month that online training is all that will be needed when the plane starts flying again. I hope this is misreported/incorrect.

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      • Originally posted by flashcrash View Post

        CNN is reporting that Boeing senior management stated as recently as last month that online training is all that will be needed when the plane starts flying again. I hope this is misreported/incorrect.
        Another pilot speaking?

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        • Originally posted by NY Times
          Specifically, the notice, known as an airworthiness directive, said that design changes to support panels in the Max’s flight deck, or cockpit, had resulted in “insufficient electrical grounding of installed equipment.”
          Ok, not a shoddy assembly issue. But another hard-to-fathom design flaw. How do flaws in such simple concepts as critical data redundancy and basic circuitry make it to the assembly line? I'm no more confident in the oversight than I was two years ago.

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          • Originally posted by Evan View Post
            Ok, not a shoddy assembly issue. But another hard-to-fathom design flaw.
            I told you so, didn't I?

            How do flaws in such simple concepts as critical data redundancy and basic circuitry make it to the assembly line? I'm no more confident in the oversight than I was two years ago.
            It doesn't seem to be a design flaw anywhere close to MCAS golden standard for design flaws.

            I don't know enough of what went on here, but the design change was related to replacing rivets with screws in those support panels which seem to be structurally grounded. It is not immediately clear to me why securing those panels with screws would offer any worse grounding that securing them with rivets. The MCAS thing on the other hand was pretty obvious and outrageous.

            I wonder how many of these "smaller" issues happen all the time in the industry and perhaps there is an AD but the planes are not grounded and it doesn't get the attention of the media.
            But this is a MAX, so it's in the spotlight.

            --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
            --- Defend what you say with arguments, not by imposing your credentials ---

            Comment


            • Originally posted by Gabriel View Post
              I wonder how many of these "smaller" issues happen all the time in the industry and perhaps there is an AD but the planes are not grounded and it doesn't get the attention of the media.
              But this is a MAX, so it's in the spotlight.
              I wonder how small the issue would have been if the problem revealed itself with a crew losing all flight displays in IMC.

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              • I didn't small. I said smaller and was comparing it with MCAS.
                And I mentioned not only the magnitude of the risk, but the magnitude of negligence in the design mistake.

                --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                --- Defend what you say with arguments, not by imposing your credentials ---

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                • Originally posted by Gabriel View Post
                  I don't know enough of what went on here, but the design change was related to replacing rivets with screws in those support panels which seem to be structurally grounded.
                  The actual AD doesn't seem to mention this; however it describes the problem as "degradation in bonds essential for the electrical grounding of equipment". The most common cause of this type of bonding failure is inappropriate metal-on-metal contact. If two dissimilar metals are in contact with some kind of electrolyte present, the less noble metal will corrode. It could be as simple as replacing (say) steel rivets with aluminum screws. This would be a rookie mistake for a Boeing electrician though, so I suspect it's more complex than this.

                  2021-09221.pdf (federalregister.gov)

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                  • Originally posted by Gabriel View Post
                    I didn't small. I said smaller and was comparing it with MCAS.
                    And I mentioned not only the magnitude of the risk, but the magnitude of negligence in the design mistake.
                    This is what bothers me:

                    But this is a MAX, so it's in the spotlight.
                    While the spotlight is definitely on the MAX, it's also in the spotlight because it was grounded again. Was the A320 grounded last month? Was any other major airframe grounded last month?

                    Was it grounded because it is in the spotlight while others, having issues of a similar urgency, were not grounded? I doubt it.

                    Did it need to be grounded? I would think so, given the fact that electrical grounding (or earthing as the Brits would have it) is a fundamental tenet of safe electrical circuitry. From what I gather, the issue could have caused a loss of instrumentation, perhaps an entire loss. That would certainly have put the MAX back in the spotlight. I don't think something of this nature is typically given compliance time.

                    Is this the end of these groundings? I hope so, but what I see here is cultural decay and, most likely, rushed, shareholder-oriented production schedules. So I doubt that too.

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                    • The keyboard Captain hath spoken!

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                      • Originally posted by Evan View Post

                        This is what bothers me:



                        While the spotlight is definitely on the MAX, it's also in the spotlight because it was grounded again. Was the A320 grounded last month? Was any other major airframe grounded last month?

                        Was it grounded because it is in the spotlight while others, having issues of a similar urgency, were not grounded? I doubt it.

                        Did it need to be grounded? I would think so, given the fact that electrical grounding (or earthing as the Brits would have it) is a fundamental tenet of safe electrical circuitry. From what I gather, the issue could have caused a loss of instrumentation, perhaps an entire loss. That would certainly have put the MAX back in the spotlight. I don't think something of this nature is typically given compliance time.

                        Is this the end of these groundings? I hope so, but what I see here is cultural decay and, most likely, rushed, shareholder-oriented production schedules. So I doubt that too.
                        I don't know.... the only incident was found by Boeing when a plane in production failed a standard manufacturing test. The planes delivered to the airplanes passed the test so the grounding was good at that point but the concern is degradation over time.

                        How long have we flown in 737 since the AD for the rudder reversals came out until the compliance date was due many years later? Or with fuel tanks with no inerting system?
                        Again, I don't know enough details of this case with the MAX grounding due to grounding issues, but I WONDER if it being a MAX has something to do with the swiftness of the measures and the publicity it gets.

                        --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                        --- Defend what you say with arguments, not by imposing your credentials ---

                        Comment


                        • Originally posted by Gabriel View Post
                          How long have we flown in 737 since the AD for the rudder reversals came out until the compliance date was due many years later?
                          Waaay too long! But that was due to Boeing fighting the findings of the NTSB every step of the way. Those findings were 'probable cause' and never proven, although it was clearly obvious after multiple incidents that a jammed rudder actuator resulting in a reversal was the most probable cause. However, because it wasn't provable, Boeing was able to negotiate a deal in 2000 with the FAA giving them years of time to comply with design changes, providing QRH procedures to handle rudder hardovers in the interim. It wasn't until 2002 that the AD was issued to fully redesign the rudder actuation architecture with redundancy. Boeing had delayed this outcome by eleven years!

                          Of course, Boeing was expecting to retire the airframe anyway and attempting to avoid a costly redesign at the end of its production run. But then came new management, the demise of the Yellowstone Y1 project, no new airframe to carry the ultrafans and the 737 would have to struggle on into a new age. We know the rest of the story...

                          In the case of the recent groundings, the threat was established and undeniable, thus the grounding. You wonder if the MAX debacle and the public attention it received had something to do with it? Absolutely! Boeing learned a hard lesson about taking risks and corrupting oversight procedures. That is the good that has come out of this.

                          But, obviously, there is still a fly in the ointment and I believe that fly is called executive management.

                          Comment


                          • Evan, you are getting me wrong. I am not judging the appropriateness of the measure. I am asking if the MAX is getting "special treatment".

                            If Embraer reported to ANAC, or ATR reported to EASA, that one of their planes in the factory failed a standard grounding test performed on all airplanes, that the issue is being traced to a recent design change which unintentionally made this grounding less robust, that the other 50 airplanes already delivered with the design change passed the same factory test successfully, and that so far after thousands of hours of flight there was no fault related to this grounding in these 50 airplanes delivered, would ANAC or EASA have grounded the affected fleet?

                            Not asking "should". Asking "would".

                            --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                            --- Defend what you say with arguments, not by imposing your credentials ---

                            Comment


                            • Originally posted by Evan View Post
                              But, obviously, there is still a fly in the ointment and I believe that fly is called executive management.
                              In this case Boeing spoke up for an issue found in their factory and informed the FAA that it was traced to a design change and that there were airplanes already delivered with the design change. That is the correct behavior. How big of a screw up was this design change in the first place, I don't know the details to tell.

                              --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                              --- Defend what you say with arguments, not by imposing your credentials ---

                              Comment


                              • Originally posted by Gabriel View Post
                                Evan, you are getting me wrong. I am not judging the appropriateness of the measure. I am asking if the MAX is getting "special treatment".

                                If Embraer reported to ANAC, or ATR reported to EASA, that one of their planes in the factory failed a standard grounding test performed on all airplanes, that the issue is being traced to a recent design change which unintentionally made this grounding less robust, that the other 50 airplanes already delivered with the design change passed the same factory test successfully, and that so far after thousands of hours of flight there was no fault related to this grounding in these 50 airplanes delivered, would ANAC or EASA have grounded the affected fleet?

                                Not asking "should". Asking "would".
                                Here's what I know: Boeing has squandered much of the faith it had earned with regulators over the prior century. The FAA isn't giving them much rope now and, understandably, are taking any sign of shoddiness or mulfunction very seriously as a symptom of more serious problems. Call it 'treatment' if you like. I call it caution.

                                In this case Boeing spoke up for an issue found in their factory and informed the FAA that it was traced to a design change and that there were airplanes already delivered with the design change. That is the correct behavior.
                                Some things seem to be fixed, such as the thing that self-reports to an agency that they are no longer quite so much in bed with.

                                But other things don't seem to be fixed, such as how a basic electrical design flaw made it through review and approval stages and all the way into production. I think it comes from pressure from on high.

                                We have to remember that the 737MAX is a reactionary fix for having been caught waaaaaaaay behind the market. Boeing justs wants to off-load these things, improve the balance sheet and then, hopefully, if needed changes have really been made in the culture, get to work on a real 21st-century replacement. I worry that corners are being cut to get there.

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