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  • #16
    Originally posted by Not Evan
    Just your basic procedurally-laden mind that has somehow again forgotten some of the most extremely basic, cowboy airmanship fundamentals of manage attitude.
    What procedure exactly are you referring to? There is no 'follow the flight director and ignore the basic instruments' procedure.

    A procedure I would have liked to see here would be, I don't know... brief the approach and tune the ILS procedure... level off at your assigned altitude procedure... approach checklist procedure... switch off the FD's when hand-flying against the active vertical mode procedure... CRM procedure... EGPWS procedure... Dual input procedure... Pilot screening procedure...

    This didn't just happen because of bad basic airmanship. This happened because they got behind the airplane, created excessive workload and lost crew resource management. It went from following a plan to improvising. It went from piloting to panicking. Panic creates tunnel vision.

    The lesson to learn here is stay ahead of it. Follow procedures that are there to help you stay ahead of it. Maintain your SA all the way down.

    Comment


    • #17
      Originally posted by Evan View Post
      What procedure exactly are you referring to? There is no 'follow the flight director and ignore the basic instruments' procedure.
      There is a procedure to follow the flight director. Good pilots generally give that close attention and do a good job, and are trained to do so.

      The question is why additional basic, fundamental cowboy procedures such as: maintain situational awareness, maintain reasonable attitudes and altitudes and keep ahead of the plane*, were forgotten by these pilots.

      *be it a Cessna 150 or a 737-236A
      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

      Comment


      • #18
        Originally posted by 3WE View Post
        There is a procedure to follow the flight director. Good pilots generally give that close attention and do a good job, and are trained to do so.

        The question is why additional basic, fundamental cowboy procedures such as: maintain situational awareness, maintain reasonable attitudes and altitudes and keep ahead of the plane*, were forgotten by these pilots.
        Not to mention why the hell this:

        [headscratch]
        The altitude capture activated, the aircraft still at 240 KIAS, the crew selected 400 feet instead of 3000 feet into the altitude window, which caused the autopilot to revert to vertical speed mode at 1200 fpm rate of descent.
        [/headscratch]

        Comment


        • #19
          Originally posted by Evan View Post
          You instruct George to maintain a 1200fpm descent and that what it does. You take George out of the game so now it's just telling you to do what you told it to do. If you don't want it to tell you this, you have to do something about it. It's all coming from you. Airbus, Boeing or what have you.
          Two choices: Shut it up or not listen to it.
          I always thought that the FD was a two edged sword. Pilots become very used, for example in an ILS approach, to follow the FD command bars rather than the ILS needles, because they know that following the command bars will keep the ILS needles centered, until one day it doesn't and they follow the command bars into a stall or into the ground.

          And today even the Cessna 172 comes with flight director!!!! So a pilot might never fly an ILS (or equivalent) approach following the ILS indication as the main reference.

          --- 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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          • #20
            Originally posted by Evan View Post
            Not to mention why the hell this:

            [headscratch] [/headscratch]
            Perhaps they were intercepting from above, were about to reach the preselected altitude and didn't note that they were already capturing the glide slope so they re-selected a lower altitude to keep in the descent and intercept the glide slope?

            --- 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


            • #21
              Originally posted by Gabriel View Post
              And today even the Cessna 172 comes with flight director and digital autopilot!!!! So a pilot might never fly an ILS (or equivalent) approach following the ILS indication as the main reference.
              Fixed!

              --- 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


              • #22
                Originally posted by Gabriel View Post
                Perhaps they were intercepting from above, were about to reach the preselected altitude and didn't note that they were already capturing the glide slope so they re-selected a lower altitude to keep in the descent and intercept the glide slope?
                Not even close.

                Comment


                • #23
                  Originally posted by Gabriel View Post
                  Two choices: Shut it up or not listen to it.
                  I always thought that the FD was a two edged sword. Pilots become very used, for example in an ILS approach, to follow the FD command bars rather than the ILS needles, because they know that following the command bars will keep the ILS needles centered, until one day it doesn't and they follow the command bars into a stall or into the ground.
                  Ah, you lost me. There are of course no ILS 'needles' in the Airbus glass terrarium. Outside of the ILS, you have three choices in manual flight on the PFD: No FD (the appropriate choice here), FD cross bars in HDG / V/S (lateral/vertical modes selected) or the PFV 'Bird' in TRK / FPA. The only problem is if the FD is following an active mode that you need to be flying in opposition to (like climbing in a descending vertical speed mode). On the ILS you just keep the bars centered as you would with the needles, no? I don't see the difference in accuracy between these indications and the old-school needles.

                  So as long as you don't mismanage the FD modes and shut off the FD when it is contradicted, you can follow the FD with total confidence (along with the primary instruments and the old windscreen 'display').

                  What I'm saying is you, the pilot, set up the FD. If you set it up wrong, it will do you wrong. Otherwise, I don't see a problem.

                  And of course, if the autopilot fails for some reason, you turn them off right away!

                  Comment


                  • #24
                    Originally posted by Evan View Post
                    Not even close.
                    At what point in the chart was the altitude selected to 400'? (honest question)

                    --- 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


                    • #25
                      Originally posted by Gabriel View Post
                      At what point in the chart was the altitude selected to 400'? (honest question)
                      According to the description, as they were passing through 3000 (their assigned altitude) the AP tried to level off so they dailed in 400 ft. Why, I ask you...

                      If you look at the graph, every downward path is approximately the 3° slope that 1200fpm (AFAIK, compare it to the glideslope angle) would yield. It seems pretty obvious looking at the graph that each attempt to level out was instead pitched to the FD prompt for -1200 V/S.

                      Comment


                      • #26
                        Originally posted by Evan View Post
                        Ah, you lost me. There are or course no ILS 'needles' in the Airbus glass terrarium. Outside of the ILS, you have three choices in manual flight on the PFD: No FD (the appropriate choice here), FD cross bars in HDG / V/S (lateral/vertical modes selected) or the PFV 'Bird' in TRK / FPA. The only problem is if the FD is following an active mode that you need to be flying in opposition to (like climbing in a descending vertical speed mode). On the ILS you just keep the bars centered as you would with the needles, no? I don't see the difference in accuracy between these indications and the old-school needles.

                        So as long as you don't mismanage the FD modes and shut off the FD when it is contradicted, you can follow the FD with total confidence (along with the primary instruments and the old windscreen 'display').

                        What I'm saying is you, the pilot, set up the FD. If you set it up wrong, it will do you wrong. Otherwise, I don't see a problem.

                        And of course, if the autopilot fails for some reason, you turn them off right away!
                        Ok, let me clarify.

                        First, yes, the Airbus has the ILS needles, in it's digital image version.

                        I used the ILS just as an example. I meant to say flying raw data vs flying the FD trusting that it will result in raw data being the desired one.

                        In manual flight, the FDis a TOOL to HELP the pilot keep the desired data, but it's the pilot duty not to RELY on that and, instead, ENSURE that the raw data is what he wants it to be REGARDLESS of what the FD is showing.

                        The problem is that pilots, when in manual flight, are most of the time flying on FD, and it's very easy to become too used to it to the point where one becomes relyant. That's because it's so much easier to follow the FD commands that to enforce the desired raw data.

                        For example take a descent at constant VS, and let's assume that someone will take care of the airspeed just to simplify the explanation. If you just focus in the vertical speed and adjust your control inputs based only on that, you will very likely end up overshooting the target to one side and another.

                        You need to establish a goal pitch that you think is reasonable for the desired VS, enforce it (using the elevator), and see what happens. So you want -2500fpm. You try and keep 0° pitch, wait for the VS to stabilize and it does so at -2000, so now you establish a new goal of -1°, fly it and keep it until the VS stabilizes and it does so at -3000fpm. So now you repeat the process with -1/2° and get the desired -2500.

                        With an ILS approach you add one more layer. Your ultimate goal is center the glide slope, but for that you establish a goal of say -700fpm, and for that you set a goal of 1° nose up and fly it. First you have to iteratively adjust your attitude goal until you find the one that gives you the desired -700fpm, and then you need to see if that goal is enough to keep the glide slope centered ot you have to adjust it. And if you got one dot low, you will now what to set a new goal of -500 fpm instead of -700 until the glide slope needle is centered again, and then restore the -700, always using pitch, not glide slope nor vertical speed, as the primary feedback of your control inputs.

                        Let me clarify that pilots don't do that, or at least they don't realize that they are doing that. They have practice and they have a good "mechanical" idea of how control inputs and airplane response interact, so they don't do all that consciously that they are doing it. But this closed-loop feedback control system is still there.

                        Now compare that to "move the elevator to center the command bar". Forget about pitch, vertical speed and glide slope. It's so easy to get used to that.

                        And not only that: studies showed that the FD is in itself a major contributor in preventing spatial disorientation and loss of control accidents. I expect that we'll see fewer cases of that in GA now that about every little plane comes with a digital cockpit with FD and AP instead of the old 6 pack.

                        But the FD is not bulletproof. The FD itself can fail, or a sensor providing info the the computer that define the FD logic can fail, or the pilot can fail when selecting the guidance mode. That's why the FD must be take as an aid to help get the desired performance or flight path, but not as the primary indicator that you are doing so as to get the desired performance or flightpath.

                        So, on the other hand, I expect to see (or we are already seeing?) a trend of relatively more accidents related with FD failures and mismanagement (and with all this kind of automations and aids). While avoiding one way to crash is creating new ways to crash, I expect the net result to be positive.

                        But pilots need to be aware of the new risks that come with solutions for old risks.

                        --- 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


                        • #27
                          Originally posted by Evan View Post
                          According to the description, as they were passing through 3000 (their assigned altitude) the AP tried to level off so they dailed in 400 ft. Why, I ask you...
                          Ah, it was the "altitude capture". I don't know why I got it was the "GS capture".

                          --- 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


                          • #28
                            Airbus Golden Rule

                            Know your FMA at all times.

                            Otherwise, Instructor had no idea what was going on (no instructor would ever knowingly allow the aircraft to descend below a cleared altitude), Captain under training had no idea what was going on.

                            But, once again, we see that the 'Dual Input' alert of the Airbus is absolutely inadequate to highlight to the pilots that it is occurring.

                            How many accidents/incidents have we had now where the 'Dual Input' alert is screaming away in the background and no-one notices/acknowledges it? Time for Airbus to go away and have another serious think about the issue, because it keeps cropping up time and time again. Remember - pilot overload = loss of hearing.

                            Comment


                            • #29
                              Originally posted by MCM View Post
                              Airbus Golden Rule

                              Know your FMA at all times.

                              Otherwise, Instructor had no idea what was going on (no instructor would ever knowingly allow the aircraft to descend below a cleared altitude), Captain under training had no idea what was going on.

                              But, once again, we see that the 'Dual Input' alert of the Airbus is absolutely inadequate to highlight to the pilots that it is occurring.

                              How many accidents/incidents have we had now where the 'Dual Input' alert is screaming away in the background and no-one notices/acknowledges it? Time for Airbus to go away and have another serious think about the issue, because it keeps cropping up time and time again. Remember - pilot overload = loss of hearing.
                              So, pilot overload = no CRM? That would be a grim reality. As with the yoke, the primary means of avoiding dual input is protocol, right? Aside from the call-out for command, Airbus gives you a verbal "dual input" alert, a warning light on the glareshield and a priority take-over button. I mean exactly how idiot proof do we have to get here?

                              Also, the A/C was leveling off after capturing the assigned altitude when somebody intentionally dialed in 400' in the altitude window on the FCU. I don't see how an instructor pilot is going to miss that. I also can't for the life of me understand why this was done? Was this another suicide attempt?

                              I only agree with you that the Airbus sidestick control is more dangerous when CRM goes out the window and panic takes over and that isn't go to happen if you are properly trained and stay ahead of the approach. The FD issues Gabriel mentions aren't even worth mentioning when you consider everything else they failed at to get into this situation. But yes, with no protocol and panic creating cockpit anarchy you might be in a better situation with a linked yoke in your hands. Unless the other pilot is much stronger than you. It didn't help on Egypt Air Flt 990, whereas at least with the sidestick you can neutralize the other pilot's input.

                              But really, what needs to be fixed here? The means of control or the discipline of control?

                              Comment


                              • #30
                                Originally posted by Gabriel View Post
                                ... in an ILS approach, to follow the FD command bars rather than the ILS needles, because they know that following the command bars will keep the ILS needles centered...
                                In a perfect world you'd check the ILS, determine the approximate appropriate input and then consult the flight director to make the PERFECT appropriate input (or "stop" and investigate if the FD's suggestions weren't appropriate.)

                                And I'm sure our pros probably do that without even thinking about it.

                                Conversely, do pilots EVER see situations where it's good that they did the extra mental step...EVER?

                                99.9999% of the time, it's a wasted mental exercise....JUST follow the FD.

                                Question to the pros- dusing your simulator work, do you ever rehearse a FD failure?
                                Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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