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  • Originally posted by Evan View Post
    I knocked up a flowchart.
    At this point I wish to state that of all the alternate universes I exist in, this one's the weirdest.
    Be alert! America needs more lerts.

    Eric Law

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    • Originally posted by Not_Evan View Post
      The real pilots responded with full corrective aileron and rudder...not sure when, but maybe after 10 or 20 degrees of bank...
      It's the same universe, but another totally accurate view of it.

      Never said this was an easy experience (are you reading all the words? How about Gabe's words?)

      Nevertheless, I would bet a beer that a lot of my ag-pilot acquaintances might be very quick to nose over if they don't like how things are 'rolling'...but alas, a totally different type.
      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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      • Originally posted by 3WE View Post
        Nevertheless, I would bet a beer that a lot of my ag-pilot acquaintances might be very quick to nose over if they don't like how things are 'rolling'...but alas, a totally different type.
        Ok, you're on. Get one of your ag buddies into a shitstorm situation where engine failure is followed by electrical bus failure and hydraulics failure. Get them working that problem, asking "what's it doing now?" with no answer available to them. Keep them focused on flying the plane... airspeed and attitude, and establishing positive climb.

        Have them commanding a bit of light roll corrections in both directions, but no stall buffet, Keep the airspeed well above vs, right where it should be, and tell them to continue climbing out to 800ft (no problem for the DC-10 on two engines, and standard procedure for engine failure), before they level off and accelerate.

        But give them no indication of stall or any reason to expect it.

        Then, over a span of seconds, in the midst of this massively confusion shitstorm, introduce a sudden, extreme roll toward the dead engine, with no stickshacker activation, accompanied by sudden yaw and a rapid drop in pitch.

        Let's see them identify that as stall and recover from that in a DC-10 below 1000ft within a few seconds.

        Note where the stall first occurs on the flight recorder and where it ends (a span of about 8 seconds, of which at least 6 secs are unrecoverable):

        Click image for larger version

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        • Originally posted by Evan View Post
          Blah Blah Blah
          Again- respect to Bobby & colleagues- as you state, but are unable to comprehend my acknowledgement: the situation is very challenging.

          That being said, the counter argument is painfully simple: "Fly the plane first" (maybe that's on Bobby's 5 memory checklists?)

          If the air tractor starts rolling maybe a little nose down along with the aileron and rudders...

          172's 737's DC-10's with bells and whistles BUT NOT stall warnings....Big Airbusses WITH stall warnings...

          Gabieie even once said something about an ATR incident and sudden, commanded roll.
          Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

          Comment


          • Originally posted by 3WE View Post
            Again- respect to Bobby & colleagues- as you state, but are unable to comprehend my acknowledgement: the situation is very challenging.

            That being said, the counter argument is painfully simple: "Fly the plane first" (maybe that's on Bobby's 5 memory checklists?)

            If the air tractor starts rolling maybe a little nose down along with the aileron and rudders...

            172's 737's DC-10's with bells and whistles BUT NOT stall warnings....Big Airbusses WITH stall warnings...

            Gabieie even once said something about an ATR incident and sudden, commanded roll.
            Did you even look at that flight recorder plot?

            3WE, the thing you aren't getting is that everything here was about AVOIDING stall and that really wasn't possible to a crew looking at good airspeed and attitude and no buffet and no stickshaker and no indication of slat retraction. Once the telltale roll occurred, there wasn't time to recover, not for a mere mortal anyway. Maybe Gabriel could have pulled it off, but every pilot involved in the post-accident sims said it couldn't be done. No blame was ever placed on the pilots.

            Comment


            • Originally posted by Evan View Post
              The crew of AA-191 were not doing stall avoidance.
              No, they were dealing with insufficient roll control authority. More speed and less AoA = better roll control authority.

              --- 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
                No, they were dealing with insufficient roll control authority. More speed and less AoA = better roll control authority.
                From the moment of engine faiilure, they were dealing with asymmetric thrust, with sufficient roll control authority. It isn't until the onset of the outer wing stall that they lose this authority. That stall comes without warning.

                ...everything here was about AVOIDING stall and that really wasn't possible to a crew looking at good airspeed and attitude and no buffet and no stickshaker and no indication of slat retraction. Once the telltale roll occurred, there wasn't time to recover, not for a mere mortal anyway.
                Do you really disagree with that?

                Comment


                • Originally posted by Evan View Post
                  Do you really disagree with that?
                  Let’s try this:

                  Pilots responding immediately to a sudden roll with a measured nose down input is well within the universe, and much more likely than a random meteor strike.

                  One more fundamental: when you have an engine failure you are generally near the ragged edge of directional control until you start leveling off.

                  It’s not cowboy improvisational stupidity to be cocked and primed for a little shove over when an engine craps out.

                  The lack of a little shove over is present in most engine failure on take off crashes.

                  We all agree that it’s harder when the ASI is ok and you are doing everything exactly as you do in the sim twice a year...
                  Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                  Comment


                  • Originally posted by 3WE View Post
                    Let’s try this:

                    Pilots responding immediately to a sudden roll with a measured nose down input is well within the universe, and much more likely than a random meteor strike.
                    The immediate response will be opposite roll input. I don't know that nose-down input is a natural response to sudden roll in close ground proximity. Especially in the absence of any other sign of stall.

                    But 3WE, look at the plots! The report confirms that the final roll to the left was the only warning the pilots had of the onset of stall. The aircraft is stalled and in a very reduced pitch attitude five seconds later.

                    First, I feel compelled to remind you once again that these are human pilots under extreme stress, workload and confusion, not 'cocked and primed for a little shove over'.

                    Secondly, there will be some span of time between a human situational recognition and the actual reduction in aoa.

                    Thirdly, obstacle clearance was more of a priority to these pilots than stall avoidance, because, by every indication, they were close to the ground and far away from stall.

                    We all agree that it’s harder when the ASI is ok and you are doing everything exactly as you do in the sim twice a year...
                    But do we agree that it is far harder when the unthinkable event occurs once in a lifetime? Sudden asymmetric stall with healthy airspeed and attitude? You don't practice for this in the sim.

                    But look, Gabriel has a point that the procedural speed reduction to V2 was neither necessary nor, in hindsight, the wisest action. The NTSB also noticed this:


                    Originally posted by NTSB Recommendations
                    Evaluating the takeoff - climb airspeed schedules prescribed for an engine failure to determine whether a continued climb at speeds attained in excess of V2, up to V2 +10 knots, is an acceptable means of increasing stall margin without significantly degrading obstacle clearance.
                    I believe that procedure has been modified since this crash, although not allowing stooges to monkey up the engine mounting procedure closed this risk scenario long ago.

                    Comment


                    • Originally posted by Evan View Post
                      The immediate response will be opposite roll input. I don't know that nose-down input is a natural response to sudden roll in close ground proximity.
                      It can be, it is for some, and it should be in some contexts (slow speed and asymmetric conditions).

                      It could have saved many accidents, including AA-191, the 2 deadly 737 rudder hardover, and most mulitengine LOC that happened after an engine failure (and let's see if we ever learn what happened with the Hercules that crashed earlier this year). Stalling is not the only way to lose roll control. If slow, assymmetric and losing roll control, reducing the AoA and increasing the speed is a damn good idea. Pulling up to raise the nose that has just fallen following the wing is, on the other hand, a terrible idea. Most of these accidents end up being a stall accident even in the cases where they do not begin as one.

                      --- 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
                        It can be, it is for some, and it should be in some contexts...
                        Put this in the context of THOUSANDS of control loss incidents from engine loss WITHOUT slat retraction and arguably pilots really should be cocked and primed for a quick measured shove.

                        Might not have HELPED 191, BUT nailing V-2 unfortunately wasn’t the answer.
                        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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