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Air Astana serious control problems, request ditching, land safely

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  • #31
    Originally posted by 3WE View Post
    If there is a control position readout that is part of the checklist, then they SHOULD check AND DETECT such problems. Repeating- I took the control checks seriously on 172's and used the memory device: thumbs points UP towards the aileron that should point UP. Took it serious because mis-rigging has crashed a lot more light planes than big planes.

    I would hope the airline guys take their TV check just as seriously and slowly and pause to not get dickleskick about what should be up and down (nor blindly do the motions like they have done thousands of times before- without really registering what they saw).
    I think I am not making myself clear,, so here it goes again, for the third time, with emphasis added:

    After congratulating these crew members for this amazing feat, giving them medals, raising statues and giving them a high monetary bonus, let's fire them for not catching such an important basic and obvious thing in the pre-flight checks, especially after the plane had undergone major maintenance. The synoptic page that should be used during the control checks is very obvious. I may even understand someone missing a fully inverted system (where all the controls go right when you turn the wheel left), but the spoilers going up and the ailerons down on the same wing should have raised all kind of red flags even if peeked with the peripheral vision.

    Doesn't give you shivers seeing things going up and down on the same wing at the same time?
    That is very different from just an inverted aileron for which you need the thumb rule to make sure.

    And by the way:
    707's, 737-200's, 727's, Early 747's, DC-9's, J-31, Saabs, Brasilias and MD-80s.
    I don't know if all of them, but many of them have things that looked like this (go and find it. Hint: zoom in):


    --- 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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    • #32
      Originally posted by Schwartz View Post
      OK, I have so many thoughts about this. Whenever I design something that is connected, I make damn sure, there is only one way the connector goes in. How could the control system parts be ambiguous enough to allow improper connection?????? The engineers should be shot for that one. The airbus incident was different, they were fixing an electronic part on the control device itself, and in replacing wires mis-soldered them. That is different.
      It is not different. In the Airbus system they routed the electric wires incorrectly and soldered them to the wrong connectors. In the E-190 they routed steel cables incorrectly and attached them to the wrong lever hole.

      1) I don't think the system was fully reversed. It was just messed up on one side, and some of the surfaces were messed up, but not all of them. I suspect that meant that they had some limited control especially at lower deflections.
      The ailerons were inverted on both sides. The spoilers were ok on both sides. The question is who had more roll power, and I will go and guess it was the ailerons or the incident would not have happened, it would have been "just"a reduced (but positive) roll authority. This was clearly not a limited control issue. Limited positive control let's you keep the plane at least roughly wings level. These guys exceeded bank angle limits all the time (rumor say they rolled inverted a couple of times), and where unable to keep even a "generally western heading" to aim for the ocean as they intended. And, especially at lower deflections.... I don't know the E-190 but in general the roll spoilers only start acting after certain minimum deflection threshold is exceeded, so at lower deflections only the ailerons would act, and those are the ones that were inverted.

      2) Same as above, I doesn't look fully reversed so the outcome of movements would not have been trivial to figure out and I suspect behaved very differently under different conditions. They had to figure enough of it out. Given they were stalling and losing control several times, I suspect it wasn't easy for someone to wander to a window to figure out what was going on with the wing surfaces.
      Well, again, how did they not crash then. I think that the main thing to realize is that the ailerons are working terrible and that you cannot control the plane's roll/bank with them. Once you realize that, the first thing to do would be refraining from using them, there are other means to control roll (mainly the rudder). Once stabilized at a safe airspeed, altitude, attitude, and hopefully in VMC, you can start the troubleshooting, analysis and test flights with incremental use of the wheel. The decision may be then ök, let's ban the wheel for the rest of the flight" (I suspect that is what they ultimately did).

      That reverse bike video is great.
      I agree. So my question is, what would you do if you get on a bike like this, suddenly discover that the handlebar is not working or is giving totally unexpected response to your inputs, and somehow you manage to survive the initial moments?
      Because I would crash in 2 seconds, but if I by miracle didn't then I would eventually (sooner rather than later) stop using the handlebar at all and revert to tilt control mode.

      By the way, it happened to me once that the handlebar got loose so it was sliding semi-freely both angularity and vertically. I didn't last 2 seconds and ended up rolling on the floor with the handlebar in my hands and the rest of the bike 6 feet away from me.

      I don't imagine that I could have done anything to avoid crashing, but even less I imagine keep riding the bike not figuring what is going on and still trying to control the bike with the handlebar. Any success scenario would include as necessary but not sufficient conditions realization of the situation (at least that the handlebar was not responding as expected or needed) AND stopping using it. So again my question is not how 1) or 2) are possible in themselves but how they were possible TOGETHER.

      --- 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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      • #33
        I wonder how much of a factor yaw was here?

        I bet a wing with the aileron deflected downward and the spoiler deflected upward has a hell of a lot of drag...
        Be alert! America needs more lerts.

        Eric Law

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        • #34
          Originally posted by elaw View Post
          I wonder how much of a factor yaw was here?

          I bet a wing with the aileron deflected downward and the spoiler deflected upward has a hell of a lot of drag...
          Yes, but in the "good" direction (pro- intended turn)

          --- 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


          • #35
            Originally posted by Gabriel View Post
            I don't know if all of them, but many of them have things that looked like this (go and find it. Hint: zoom in):
            Always on, mechanical fight control indicators? Not on the 190. I think the synoptic page looks like this:Click image for larger version

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            • #36
              Originally posted by Gabriel View Post
              The ailerons were inverted on both sides. The spoilers were ok on both sides. The question is who had more roll power, and I will go and guess it was the ailerons or the incident would not have happened, it would have been "just"a reduced (but positive) roll authority... I don't know the E-190 but in general the roll spoilers only start acting after certain minimum deflection threshold is exceeded, so at lower deflections only the ailerons would act, and those are the ones that were inverted.
              I think the roll spoilers are more effective at high speeds. The spoilerons in particular. Also, spoilers create roll by creating drag, by dropping the onside wing, so they would be more hazardous at low speed/low altitude.

              I think this incident makes a good case for split-able speedbrake levers though... Some sort of guarded disconnect lever as we have on the yokes. Maybe more effective at low speed than differential thrust anyway...

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              • #37
                One other thought ... couldn't they just fly it through the autopilot? The yokes would be going the wrong way but rigging shouldn't affect autopilot...

                Comment


                • #38
                  Originally posted by Gabriel View Post
                  go and find it. [a sea of gauges, knobs and lights wrapped in Turquoise]
                  No...

                  As humorously depicted in the movie Airplane!, airliners have a LOT of gauges and knobs and blinking lights.

                  AND in spite of a lot of parlor talk and occasional peeks in the cockpit and MSFS, sitting in a cockpit in a Virginia? museum once, I never noted a control-surface position indicator...other than the flap indication.

                  Not arguing against what you say- but don't feel like searching for a "needle in a haystack" when I have rolled in the hay a few times...you wanna direct me to it, great.

                  Actually- how about a checklist: "Flight controls free and correct".
                  Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                  Comment


                  • #39
                    Originally posted by Evan View Post
                    I think the roll spoilers are more effective at high speeds. The spoilerons in particular. Also, spoilers create roll by creating drag, by dropping the onside wing, so they would be more hazardous at low speed/low altitude.
                    Ummm….you wanna rethink that?

                    There may be a few correct comments, but ummmm…...
                    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                    Comment


                    • #40
                      Originally posted by 3WE View Post
                      Ummm….you wanna rethink that?

                      There may be a few correct comments, but ummmm…...
                      Ding, Ding, Ding, we have a winner.

                      Comment


                      • #41
                        Originally posted by Evan View Post
                        I think this incident makes a good case for split-able speedbrake levers though..
                        Should we install that right over next to that TOPMS thingy?

                        Comment


                        • #42
                          Originally posted by Evan View Post
                          I think the roll spoilers are more effective at high speeds.
                          All controls are more effective at high speed but compared with and relative to the ailerons? Rudder the opposite.

                          The spoilerons in particular.
                          What? I've heard of flaperons, elevons, rudderons, rudderators and even elerudderons. But spoilerons? It's a first.

                          [qupte]Also, spoilers create roll by creating drag, by dropping the onside wing, so they would be more hazardous at low speed/low altitude.[/quote]
                          Whaaaat? The spoilers do create drag, yes, like any control surface that you stick into the wind. But that's not the mechanism how they create roll. The SPOILERS create roll by SPOILING the lift in the affected area, and the larger the deflection the more lift they spoil. Aw, let's be honest, they push air up so air pushed them down. Very much like the up-going aileron.
                          So you may want to re think the "so" part of the sentence (take into account that there are planes that use spoilers as the ONLY means of roll control)

                          I think this incident makes a good case for split-able speedbrake levers though... Some sort of guarded disconnect lever as we have on the yokes. Maybe more effective at low speed than differential thrust anyway...
                          I was thinking split-able flaps..

                          --- 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


                          • #43
                            Originally posted by Evan View Post
                            One other thought ... couldn't they just fly it through the autopilot? The yokes would be going the wrong way but rigging shouldn't affect autopilot...
                            Well, that depends on what was the misrigging point and at what point the autopilot servos connect to the mechanism. But I would tend to think that, if the AP controls the ailerons, it would have been reversed too.

                            --- 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


                            • #44
                              I am really surprised that no one has brought up R/C flying on this thread. When the A/C is flying towards you, left is right and right is left. Not easy for a real pilot to master, believe me I have tried. It has not ended well on all three occasions.

                              Comment


                              • #45
                                Originally posted by Gabriel View Post
                                What? I've heard of flaperons, elevons, rudderons, rudderators and even elerudderons. But spoilerons? It's a first.
                                Assymetrical spoilers used for roll control. They've been around for quite a while, including on aircraft without ailerons.

                                Whaaaat? The spoilers do create drag, yes, like any control surface that you stick into the wind. But that's not the mechanism how they create roll. The SPOILERS create roll by SPOILING the lift in the affected area, and the larger the deflection the more lift they spoil. Aw, let's be honest, they push air up so air pushed them down. Very much like the up-going aileron.
                                The difference is that, with ailerons, one wing is decreasing in lift while the other is increasing in lift, so, for that reason alone, there shouldn't be an overall loss of altitude (Gabriellian physical hairsplitting aside). With spoiler control, one wing is decreasing lift with no corresponding increase in lift on the opposite wing, so a loss of altitude, from that reason alone, will occur. Thus, roll via spoilers alone at very low altitude comes with the caveat that, all other things being equal, the wing will drop lower to the ground than it would with roll via ailerons alone.

                                I was thinking split-able flaps..
                                A bit too slow in transit methinks.

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