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  • #16
    Originally posted by 3WE View Post
    5 minutes of full aft stick and a steady, wallowing descent.
    3BS translation: 3 minutes and 27 seconds of full aft stick just after the FD's (which, by skipping procedure in favor of basic airmanship, were left on) commanded a 20deg ANU pitch before blipping out for good. Those were the final 3 minutes and 27 seconds when the PF was entirely panic-stricken and responding to pure instinct. At that point, yes, you could say he was behaving insanely.

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    • #17
      Originally posted by Gabriel View Post
      I remember. I also remember thinking (and saying) that the AoA envelope protection should not be eliminated in Alternate law where you are getting consistent AoAs from all 3 vanes. Degraded may be, but not eliminated. If you can still trigger a "STALL STALL" aural warning, you can keep the plane from exceeding the stall AoA by 40 degrees. Yes, stall AoA varies with Mach number, but you can at least provide protection against exceeding the max stall AoA (minimum Mach number) and if you stall at a high Mach (which is NOT what happened here) you would still be exceeding the real stall AoA by just a few degrees, and the recovery would be much easier and quicker if you have to reduce 5 degrees at 180 kts than if you have to reduce 40 degrees at 100 kts.

      Alternate law where you have no AoA max protection, no low energy protection, no low speed stability (replaces the low energy protection in ALT1 but is lost in ALT2), and no pitch envelope protection, but you keep the normal law's autotrim and stick-to-load-factor or to-pitch-rate control law, looks very inadequate to me. If you are going to let me do do anything with the pitch, at least give me AoA feedback. That feedback doesn't require any logic, just make the deflection of the elevator proportional to the deflection of the stick and exclude the stabilizer unless commanded. Not that it would have made any difference in this specific case because "I have been pulling up the whole time" (or maybe it would because the plane would have not achieved these crazy AoAs without the stabilizer going fully nose-up.
      You have to keep in mind that AoA and pitch envelope protections were never meant to make the plane idiot-proof and that Alternate 2 was designed with a more or less stable aircraft in mind, where load factor longitudinal law will be beneficial over direct law with no trim feedback. We can hardly blame the engineers here for not providing for the upset scenario that occurred here, which would never have occurred with a properly vetted and trained crew (even a fatigued one). You have to rewind to two key events: the failure to follow memory procedure (and any CRM) and the flawed manual flight inputs that caused the a/c to leave stable flight. Prevent these two things from happening and the rest is academic.

      I also recall you suggesting a provisional auto-pilot mode to keep the a/c stable on pitch and power autoflight until air data conflicts resolve. I completely agreed with that.

      Comment


      • #18
        Originally posted by Evan View Post

        The most fundamental aspect of airmanship is situational awareness. Without it, we have seen seasoned airman use their airmanship to fly straight into the ground. But you'll never get past the idea that airmanship is some sort of inherent superpower than is impossible to thwart with human factors and misleading instrumentation in IMC. So carry on.
        Cape airways… throttle, mixture, props, cowl flaps. No autopilot. No FMC, no primary or alternate law. Minimal ability to climb above weather. Operations from lots of smaller airports. Single pilot operations…to date, no relentless pull ups. I am impressed…with them.
        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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        • #19
          Originally posted by Evan View Post
          You have to keep in mind that AoA and pitch envelope protections were never meant to make the plane idiot-proof and that Alternate 2 was designed with a more or less stable aircraft in mind, where load factor longitudinal law will be beneficial over direct law with no trim feedback. We can hardly blame the engineers here for not providing for the upset scenario that occurred here, which would never have occurred with a properly vetted and trained crew (even a fatigued one). You have to rewind to two key events: the failure to follow memory procedure (and any CRM) and the flawed manual flight inputs that caused the a/c to leave stable flight. Prevent these two things from happening and the rest is academic.
          Yes, I am getting academic, and I fundamentally 100% disagree with that regardless of AF44 (as I said, with the kind of irrational control inputs they did they would have stalled a dove if they had the chance). The FARs (and I suppose that the EASA rules too) REQUIRES a specific control feedback in terms both of defection and force. Airbus's normal law flagrantly VIOLATES that requirement. I don't have the details but to certify the plane in this condition they must have provided an alternative mean of compliance, i.e. they had to prove that what they were doing offered an at less equivalent leve of safety that the requirement. And I have a strong suspicion that envelope protections played a strong role in that. So I don't know how (and if I knew I suspect I would disagree) they managed to pull a certification where they can have normal control law (no feedback on AoA or speed) without normal law envelope protections.

          If you are under stress, fighting for situational awareness, task-saturated, confused and hyper-focused in only some of the important things and not being able to pay attention to others (like not stalling), you are much more likely to stall if you can do so without increasing levels of nose-up input (in terms of both deflection and force) that if you need to increase the pull-up to increase the AoA. Apparently, once you pitched 10 degrees nose up and are climbing at 7000 fpm, the plane will try to keep the pitch or vertical speed even if you release the stick at that point, and to do so it would need to apply increasing levels of nose-up elevator and/or stabilizer, and without alpha floor, alpha max, low speed protection, and etc, I don't see why it wouldn't happily stall the plane all by itself without further pilot intervention.

          Actually, on a second thought, and while my opinion is still academic and specifically tied to AF447, I would like to go back and check the FDR data to see how the elevator and stabilizer positions evolved in comparison with the stick inputs. I.e. how much of that was in response to the pilot pulling up (i.e. demanding either an increase in vertical speed or a positive pitch rate) and how much was the plane itself trying to keep the pitch or vertical speed. I tried to find the FDR data or charts but filed. If you have them or can find them, please let me know.

          --- 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


          • #20
            Originally posted by Gabriel View Post

            Yes, I am getting academic, and I fundamentally 100% disagree with that regardless of AF44 (as I said, with the kind of irrational control inputs they did they would have stalled a dove if they had the chance). The FARs (and I suppose that the EASA rules too) REQUIRES a specific control feedback in terms both of defection and force. Airbus's normal law flagrantly VIOLATES that requirement. I don't have the details but to certify the plane in this condition they must have provided an alternative mean of compliance, i.e. they had to prove that what they were doing offered an at less equivalent leve of safety that the requirement. And I have a strong suspicion that envelope protections played a strong role in that. So I don't know how (and if I knew I suspect I would disagree) they managed to pull a certification where they can have normal control law (no feedback on AoA or speed) without normal law envelope protections.
            I suspect the plane was certified in normal law with provisions for degraded control if a major system failure occurred. The alternate means of compliance might have been a synthetic voice that repeatedly calls out STALL STALL STALL. (It wasn’t required to be idiot-proof). If the empennage pitots on the 737 fail, I believe you lose artificial feel, but it was still certified. You don’t certify airframes in degraded conditions as long as they have a means to remain controllable.

            If you are under stress, fighting for situational awareness, task-saturated, confused and hyper-focused in only some of the important things and not being able to pay attention to others (like not stalling), you are much more likely to stall if you can do so without increasing levels of nose-up input (in terms of both deflection and force) that if you need to increase the pull-up to increase the AoA.
            The Airbus cockpit is designed around CRM. One pilot focused on the situation awareness and checklist procedure while the other pilot focuses on not stalling. If you are not adhering to CRM, you are not flying the Airbus. You might as well go weep in the lav because you are a dangerous presence in the cockpit.

            Apparently, once you pitched 10 degrees nose up and are climbing at 7000 fpm, the plane will try to keep the pitch or vertical speed even if you release the stick at that point, and to do so it would need to apply increasing levels of nose-up elevator and/or stabilizer, and without alpha floor, alpha max, low speed protection, and etc, I don't see why it wouldn't happily stall the plane all by itself without further pilot intervention.
            Actually, in Alternate 2, even in level flight the airplane would have eventually stalled if the thrust remained locked and too low as the plane will increase AoA to preserve the flight path. But before that happens, it would say STALL STALL STALL.

            I tried to find the FDR data or charts but filed. If you have them or can find them, please let me know.
            They have vanished from the internet. I have them in an older computer somewhere.

            Comment


            • #21
              Originally posted by Evan
              …the FDs…commanded a 20deg ANU pitch before blipping out for good.
              Yeah, probably nowhere in the FCOM does it discuss whether 20 degrees nose up is a good idea at coffin corner conditions…

              Still, there’s that Uber import 4-ate memory checklist that only applies to 172s I guess. Flyate the goshate darnate airplaneate.
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

              Comment


              • #22
                Originally posted by 3WE View Post

                Yeah, probably nowhere in the FCOM does it discuss whether 20 degrees nose up is a good idea at coffin corner conditions.
                At 02:11:41 they were nowhere near coffin corner. In fact, they were in a deep stall at a high sink rate being flown by an entirely disoriented and panic-stricken pilot. The FD can become quite influential at that point.

                Comment


                • #23
                  Originally posted by Evan View Post

                  100% on the money about pilots having a deep understanding for the type they are flying. Otherwise, he is confirming some factors I have previously brought up here, specifically the initial altimeter error indicating a loss of altitude (which might have prompted the intial climb from level flight) and the role played by the erroneous flight directors to encourage sustained pitch-up input (and thus the supreme importance of learning and following memory procedures like gospel). There are also a few new insights here, such as the role of the yaw damper in mitigating roll during the stall (and thus making the stall less obvious, though still quite obvious).

                  One very crucial recommendation I didn't see in the final report is a software fix to keep the AoA valid even at 'impossible' values. Making this change would have kept the stall warning active and prevented any confusion from that source. It's better to have an occasional erroneous stall warning than a deactivated one that reactivates when the AoA is reduced. A simple software fix. Has it been done?
                  My kudos (which seems to have sources in the Greek language: my respect, in English), to my friend Gabriel. He again brought up a case which all of us have intensively discussed,
                  when it had happened, on June 1st 2009.

                  More than 13 years ago.

                  And all of the 2009 jetphotos heroes seem to be on board again. Gabriel, 3WE, you Evan, and me. I just wonder, only 4 "seniors" (me included) have survived?

                  More than 14 years now, at least for me, here on this brilliant aviation platform.

                  As far as I remember this very dark day in June 2009, the PF question quite soon was answered.

                  No survivors on board, i.e. 216 dead passengers and 12 dead crew members on board. So, all dead on board.

                  I tend to repeat myself, but didn't I say that Rio de Janeiro is so far away from Paris or from my home airport, that there should have been professional support for
                  Captain Dubois.
                  In person of a second experienced four stripe Flight Captain on board that long haul flight.

                  Dubois was alone with his four stripes on this... without lookin that up... 12 hour flight . I know that especially on real long haul flights (more than 5000 nautical miles)
                  there are one or two airlines who fly such routes with two experienced four stripe Flight Captains .

                  PF at the moment of the catastrophe was a F/O who afaik was quite new on the Airbus A330, owner of the ATPL license only since 2007, at a catastrophe which happened in June 2009.

                  So, this Airbus was equipped with one very experienced Four stripes Flight Captain.

                  Plus one A330 Flugschüler (en.: student pilot), who unfortunately with his 2 years of experience as an
                  ATPL license owner was the PF who brought down that A330.

                  Let me ask you, Evan, only one question on this beautiful day on the road to Chistmas.

                  Is it true that I am able to fly an Airbus A330 long haul with 228 souls on board from Rio to Rhein/Main after I own the ATPL license
                  for not more than 22 or 23 months,
                  without that during every second of my attendance in the cockpit
                  one of the two experienced Flight Captains on board look over my shoulder?!

                  The German long haul is alive, 65 years and still kicking.
                  The Gold Member in the 747 club, 50 years since the first LH 747.
                  And constantly advanced, 744 and 748 /w upper and lower EICAS.
                  This is Lohausen International airport speaking, echo delta delta lima.

                  Comment


                  • #24
                    He's back

                    Comment


                    • #25
                      Yes. If that's a reason for you to celebrate.

                      Btw, ARG vs CRO, someone with a result? (active since 60 minutes, the second half is running...)

                      Oyea. (oops, I must confess I am not neutral) .
                      Last edited by LH-B744; 2022-12-13, 20:29. Reason: Oyea.
                      The German long haul is alive, 65 years and still kicking.
                      The Gold Member in the 747 club, 50 years since the first LH 747.
                      And constantly advanced, 744 and 748 /w upper and lower EICAS.
                      This is Lohausen International airport speaking, echo delta delta lima.

                      Comment


                      • #26
                        Another question from someone not experienced in the 'Bus'. With normal flight controls if you are holding the nose up you would get buffeting in the control wheel. Does that apply in the 'Bus' as well???

                        Comment


                        • #27
                          Mr Messi, what did you feel when the referee officially has ended this match?

                          ".... "

                          Dear congratulations! Argentina really strong.
                          The German long haul is alive, 65 years and still kicking.
                          The Gold Member in the 747 club, 50 years since the first LH 747.
                          And constantly advanced, 744 and 748 /w upper and lower EICAS.
                          This is Lohausen International airport speaking, echo delta delta lima.

                          Comment


                          • #28
                            Originally posted by LH-B744 View Post

                            Let me ask you, Evan, only one question on this beautiful day on the road to Chistmas.

                            Is it true that I am able to fly an Airbus A330 long haul with 228 souls on board from Rio to Rhein/Main after I own the ATPL license
                            for not more than 22 or 23 months,
                            without that during every second of my attendance in the cockpit
                            one of the two experienced Flight Captains on board look over my shoulder?!
                            Depends. If you fly for Air France you just need to pass a course in mime and have some hours in a Peugeot. Apparently.

                            But I don't know where you're getting that. The right seat F/O on AF447 got his ATPL in 2001 and had almost 3000 hours in total. Hardly a Flugschüler. Also, the left seat F/O had almost three times the on-type experience as Capitan Fourstripe. And, as we often point out on this forum, hours aren't necessarily the measure of wisdom.

                            Comment


                            • #29
                              Originally posted by kent olsen View Post
                              Another question from someone not experienced in the 'Bus'. With normal flight controls if you are holding the nose up you would get buffeting in the control wheel. Does that apply in the 'Bus' as well???
                              Well, no, since there is no control wheel you would not feel it there. But you would definitely feel it everywhere else. AF447 experienced strong buffet vibrations going into the stall. Buffet and a nagging voice calling out STALL STALL STALL. If that doesn't tip you off then bonne nuit.

                              Comment


                              • #30
                                Originally posted by Gabriel View Post
                                Look, I intended to post this video in the original thread just because it is VERY good. With very complete and accurate information, very well explained, and presented in a very appealing fashion.

                                I don't think that we are learning much new with this video, and even less than our opinions already discussed ad-nauseum in the original thread and many others are going to change because of this video or with further discussion.
                                THAT

                                --- 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

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