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  • #91
    We all know the old saw about Airbus being dangerous because the protections are inconsistent between control laws. What that misses is that knowing the reversion laws on an Airbus is as fundamental as knowing the stickshaker on a Boeing. When a Boeing pilot feels shaker, if that pilot does not instinctively think 'stall warning, watch the pitch and power', that pilot is not a pilot. When an Airbus pilot gets the indications of alternate law (which include a master caution) and that pilot does not instinctively think 'hard stall protection lost, watch the pitch and power', that pilot is not a pilot.

    Each methodology has strengths and weaknesses. Boeing pilots get a more physical feedback than Airbus pilots (though buffet is still quite felt). But in downbursts or critical terrain conflicts you are much better off in an Airbus. Overall, in almost 100% of flights, a protected aircraft is the safer one.

    But, it the pilot is not a pilot, then good luck.

    Comment


    • #92
      Evan:

      May I write Airbus a letter, suggesting that training be updated to remind pilots that relentless pull ups can cause a lot of airplanes to stall, including alternate-law A-330s, AND that it’s not a good reaction to A RASH of warnings, unless you are dangerously near terrain?

      Thanks in advance.
      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

      Comment


      • #93
        Originally posted by 3WE View Post
        Evan:

        May I write Airbus a letter, suggesting that training be updated to remind pilots that relentless pull ups can cause a lot of airplanes to stall, including alternate-law A-330s, AND that it’s not a good reaction to A RASH of warnings, unless you are dangerously near terrain?

        Thanks in advance.
        Dear Mr. 3WE,

        Thank you for your kind letter. Rest assured that we at Airbus have always built upon the assumption that all licensed airline pilots have had adequate training in the basic stall characteristics that you describe both in their introductory pilot training and in their Airbus type ratings. We do not at present offer an idiot-proof airplane for non-pilots. The procedure in our FCOM's calls for pitch (AoA) reduction as the first instant recall procedural item following a stall warning. To make the stall warning instantly identifiable, we have it call out "STALL STALL STALL" rather insistently. We hope this answers your inquiry.

        Respectfully,

        Airbus Media Relations
        Troll Division

        Comment


        • #94
          Originally posted by Evan View Post

          I think you might be living in a universe parallel with yourself.

          The first statement comes off to me as scarebus legend: ‘Airbus pilots learn to pull up relentlessly’. There are two situations I can think of where pulling up relentlessly would be taught (directly or indirectly). Both are in ground proximity and both are also taught for the 737.

          Otherwise, Airbus pilots are taught to remain in the envelope with careful, measured sidestick inputs. A.k.a Airmanship.

          So what is your point (or agenda) there?
          Dude....

          3we
          Except, I almost never favor a relentless pull up…unless there’s a REALLY GOOD, PARTICULAR REASON…
          Admittedly, if you WANT to stall, it’s a really good, particular reason.

          Gabe
          In an Airbus, there are a number of things that would qualify as a good reason to relentlessly pull up(1), which would not qualify as good reasons in a 737 or a Boeing.
          (1) Small but binding print: As long as the plane is in Normal Law.

          Evan
          1) Wind shear
          2) Obstacle or terrain clearance
          What else?

          Gabe
          You just mentioned 2 things that are NOT "you WANT to stall" which are good reasons to relentlessly pull up.
          2 is a number.
          Point is that pilots get to know and trust the plane's ability to to handle a relentless pull up without fear fo stalling (fine print still applies but may get lost under startle and panic).
          Do you understand the difference between teach and learn? Do you think there are ways of learning other than being directly taught something? Do you think that there are things that can be learned from teaching even when that thing was not what was directly taught? Do you think that Airbus pilots practice relentless pull-ups in the sim and see that the the plane cannot stall regardless of how much they pull? (fine print applies but may be overlooked under high stress, overload, panic and confusion). Do you think that Airbus pilot study that the plane will not go more than 30 deg ANU, 15 deg AND, 67 deg bank, overspeed, over-G, or stall, regardless of what they do with the stick? (again, fine print applies). Do you think that experiencing these envelope protections is something that may be practiced in the sim perhaps during type rating, to demonstrate how the protections work? Do you understand that I am NOT saying that anybody ever told any Airbus pilot "if you experience a stall warning, just pull up relentlessly"?

          And...

          There are two situations I can think of where pulling up relentlessly would be taught (directly or indirectly). Both are in ground proximity and both are also taught for the 737.
          Really, Evan? Are you ok? Do you think that Boeing may train on a limit on how much the pilot can pull back while Airbus may train that it is ok to pull the stick all the way back and hold it there if needed?

          --- 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


          • #95
            Originally posted by Evan View Post
            We all know the old saw about Airbus being dangerous because the protections are inconsistent between control laws. What that misses is that knowing the reversion laws on an Airbus is as fundamental as knowing the stickshaker on a Boeing. When a Boeing pilot feels shaker, if that pilot does not instinctively think 'stall warning, watch the pitch and power', that pilot is not a pilot. When an Airbus pilot gets the indications of alternate law (which include a master caution) and that pilot does not instinctively think 'hard stall protection lost, watch the pitch and power', that pilot is not a pilot.
            Exactly. And that is why Bonin was not a pilot. I rest my case.
            (And neither was Renslow)

            Just some clarification on my position (things that I already said in this thread but, you know, it is not always well understood).

            I think that AIrbus-style envelope protections are GOOD.

            While of course nobody wants to lose envelope protections when the control law is degraded (to avoid the inconsistencies that you mentioned), that may be unavoidable (there is a reason why the control law was degraded to begin with). That doesn't mean the way that happens cannot be improved (especially in the hinsight of AF447). For example. alpha max depends on Mach number. If Mach is lost, you could set a degraded alpha max at the highest value (which corresponds to the lowest Mach). You may still enforce that degraded alpha max protection. Of course the plane may (and more likely will) stall earlier than that, if the pilot disregards other signs of an impending stall, but it will limit how much you can go into the stall. You would not find yourself in a situation where you are with 45 degrees of AoA and the stabilizer fully trimmed nose up to the stop, and the plane still honoring your "but I have been pulling up all the time" stick inputs.

            The part that I don't like is that in Alternate Law you lose all low speed and AoA hard and soft protections (except the stall warning) but the pitch response to stick input remains in direct law which lacks AoA feedback. Note that that doesn't happen even in direct law. In direct law, when you enter the slow speed regime (alpha prot) the stick response changes from load factor / pitch rate demand to AOA demand.

            --- 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


            • #96
              Originally posted by Evan View Post

              Dear Mr. 3WE,

              Thank you for your kind letter. Rest assured that we at Airbus have always built upon the assumption that all licensed airline pilots have had adequate training in the basic stall characteristics that you describe both in their introductory pilot training and in their Airbus type ratings. We do not at present offer an idiot-proof airplane for non-pilots. The procedure in our FCOM's calls for pitch (AoA) reduction as the first instant recall procedural item following a stall warning. To make the stall warning instantly identifiable, we have it call out "STALL STALL STALL" rather insistently. We hope this answers your inquiry.

              Respectfully,

              Airbus Media Relations
              Troll Division
              Ha! Good one.
              Side comment: Bolded/underlined part was not the case in the times of AF447. It is much better now, take a look:
              /https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/what-is-stall-how-a-pilot-should-react-in-front-of-a-stall-situation.pdf

              --- 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


              • #97
                Originally posted by Gabriel View Post

                Exactly. And that is why Bonin was not a pilot. I rest my case.
                (And neither was Renslow)

                Just some clarification on my position (things that I already said in this thread but, you know, it is not always well understood).

                I think that AIrbus-style envelope protections are GOOD.

                While of course nobody wants to lose envelope protections when the control law is degraded (to avoid the inconsistencies that you mentioned), that may be unavoidable (there is a reason why the control law was degraded to begin with). That doesn't mean the way that happens cannot be improved (especially in the hinsight of AF447). For example. alpha max depends on Mach number. If Mach is lost, you could set a degraded alpha max at the highest value (which corresponds to the lowest Mach). You may still enforce that degraded alpha max protection. Of course the plane may (and more likely will) stall earlier than that, if the pilot disregards other signs of an impending stall, but it will limit how much you can go into the stall. You would not find yourself in a situation where you are with 45 degrees of AoA and the stabilizer fully trimmed nose up to the stop, and the plane still honoring your "but I have been pulling up all the time" stick inputs.

                The part that I don't like is that in Alternate Law you lose all low speed and AoA hard and soft protections (except the stall warning) but the pitch response to stick input remains in direct law which lacks AoA feedback. Note that that doesn't happen even in direct law. In direct law, when you enter the slow speed regime (alpha prot) the stick response changes from load factor / pitch rate demand to AOA demand.
                Maybe while they're reprogramming the thing, they could also add a little code so the flight director doesn't call for a sustained nose-up pitch in situations where it's guaranteed to stall the aircraft?
                Be alert! America needs more lerts.

                Eric Law

                Comment


                • #98
                  Originally posted by Gabriel View Post

                  Ha! Good one.
                  Side comment: Bolded/underlined part was not the case in the times of AF447. It is much better now, take a look:
                  /https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/what-is-stall-how-a-pilot-should-react-in-front-of-a-stall-situation.pdf
                  Again, Evan misses the point.

                  Based on ATLs comments, he’s a decent pilot AND the Airbus is a fine plane.

                  But MORE THAN ONE PERSON has fouled up the pull up. My proposal wasn’t to change their plane, but instead their training: HEY, EVER HEARD ABOUT STALLS AND CONTROL STICKS BENT BACKWARDS?

                  And yeah Boeing dudes do it too.

                  Since Evan sees nothing wrong, has he offered an economical way to identify and defer Bonins (and avoid lawsuits) when Bonin was able to get the relevant ratings?
                  Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                  Comment


                  • #99
                    Originally posted by elaw View Post

                    Maybe while they're reprogramming the thing, they could also add a little code so the flight director doesn't call for a sustained nose-up pitch in situations where it's guaranteed to stall the aircraft?
                    Like autopilot, it should be inop when the air data is unreliable and remain that way until switched back on. Maybe they’ve changed it since then.

                    Comment

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