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  • #76
    Originally posted by Gabriel View Post
    Read carefully what you've just written. Are you being fair? Because I am smelling confirmation bias.
    If you after careful reflection you still don't agree, we can discuss.

    Because you still got the wrong picture. You've taken off in IMC, are climbing out and you fly through a flock of birds that damage your pitot tubes.
    1) Don't crash against the ground. You don't see what's around you. Are you below a safe altitude? Memory items to ensure a reasonable climb.
    2) When you reach a comfortable location and altitude to troubleshoot, level off using the QRH tables.
    3) Stabilize the speed using the QRH flight technique.
    4) Troubleshoot.
    5) Still no valid speed insdication? Ok, it seems that you will have to complete the flight with no speeds. What's next? You can't return to land in IMC, you need VMC at least for the landing. There is a suitable airpot over there across the mountain range but you also need to save fuel. So you will need to a) Climb to the desired and safe cruise altitude (table), b) level off at the desired cruise altitude and c) descend when approaching the diversion airport.
    Ok, I finally located the FULL QRH procedure and I see what you are saying. The Memory Item values are for climb. The level-off value for the A330 above 190t is 3 deg / 94.3 N1. I'm not certain what the Memory Procedure yields but it is certainly a climb at 5 deg / CL based on the fact that, when the crew advanced the TL's to the CL detent, the N1 increased to 104% (I expect 5 deg and 104% would produce a moderate climb at that weight/altitude). On the fourth page of the procedure are further tables for pitch/power in CLIMB, CRUISE, DESCENT and APPROACH if needed.

    I think one thing that is confusing me is that these procedures were never written or intended for the sudden and total loss of airspeed data (i.e. ice ingestion) and autoflight in the cruise-level phase of flight, as the phenomena of supercooled water and high elevation of ice crystals was not well-understood and therefore that was previously not considered a plausible (or even possible) scenario. So memory (instant recall) items do not exist for this scenario.

    So, the memory procedures, which yield a climbing flight path, do not apply to cruise-level flight unless "the safe conduct of the flight is affected" (I assume this means wherever a climb is necessary), but the QRH procedure still calls for, as a first action after shutting down the AT and FD's, factory-engineered pitch and power settings. As I said in my previous post, I'm fine with that. My concern has always been that pilots avoid improvising on pitch and power, even if they consider it "known" to them, and that the initial commands departing from the current flight path are guided by these reference values.

    There are problems with that though. For one thing, the total loss of speeds in high-altitude turbulence results in an immediate loss of autoflight and need for manual intervention before the QRH values can be obtained. The pitch attitude prior to the disconnect could be quickly lost in that choppy, rolling transition. Therefore, it seems logical that a similar pair of broad, cruise-level-flight pitch/power targets should also be provided as a Memory Item for all weight categories above and below FL250, just to stabilize within the safe envelope for a minute or so. Again, I agree that a provisional autoflight mode is the most optimum idea and I don't see any reason that it can't, or shouldn't, be implemented.

    In any case, I remain steadfastly opposed to the idea of improvisation here. That has to stop. WIth no speed reference, misleading altitude and vertical speed references and the FD in self-destruct mode and the autothrottle in stealth mode, the procedures and engineering-derived pitch and power targets must be expediently followed.

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    • #77
      Originally posted by Evan View Post
      I remain steadfastly opposed to the idea of improvisation here.
      I steadfastly support the idea that when you are overwhelmed and don't have a clue what to do, that it is OK to default to broadly applicable fundamentals unless you were trained that this was some phugoided system where the fundamental rule will result in the wrong thing. (I'm sure such situations exist and am sure there is training to be sure NOT to do it the 172 way).

      Defaulting to fundamentals is:

      1. Simpler when you are totally clueless.

      2. It's pretty damn close to the exact procedure ATL prescribed of: Fly on, assure you are stable and then start high-quality trouble shooting.

      3. It would have worked that night (I double steadfastly proclaim).

      I very much agree that total stupid improvisation which goes almost totally against basic, broadly-applicable fundamentals is wrong (unless there are specific reasons and training for a type-specific system that works other than basic aerodynamic rules).
      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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      • #78
        Originally posted by TeeVee View Post
        this brings new meaning to the word "stubborn"
        LOUD NOISES!!!!!

        https://www.youtube.com/watch?v=aTRSmjUfYrs
        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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        • #79
          Originally posted by 3WE View Post
          I very much agree that total stupid improvisation which goes almost totally against basic 172 fundamentals is wrong (unless there are specific reasons and training for a type-specific system that works other than basic aerodynamic rules).
          But how do you know which you are going to get 3WE, the intact fundamentals of the broken ones? Remember, human factors are rather awesome. Bonin was an experienced glider pilot. He had a solid understanding of fundamentals, in his normal, intact brain. Pilots need a reference in this dangerous state of confusion. And passenger's need to be protected from them. And automation could do that here.

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          • #80
            Originally posted by Evan View Post
            And automation could do that here.
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            • #81
              Originally posted by Evan View Post
              But how do you know which you are going to get 3WE, the intact fundamentals of the broken ones? Remember, human factors are rather awesome. Bonin was an experienced glider pilot.
              Absolutely correct.

              The best evidence that you can't know what to expect is that Bonin, the glider pilot AND EXTENISVELY TRAINED A-300 COPILOT, did not select the right NAV ADR DISAGREE" ECAM83% N1 alpha prot AoA RECMAX THRUST RED ALT WTF NOR the fundamental "let if fly" and "don't pull up relentlessly" procedures.

              So what training is a human more likely to remember when the excrement hits the blower?:

              NAV ADR DISAGREE" ECAM83% N1 alpha prot AoA RECMAX THRUST RED ALT WTF- REPEAT FROM MEMORY...

              OR

              NAV ADR DISAGREE" ECAM83% N1 alpha prot AoA RECMAX THRUST RED ALT WTF- AND remember that is basically saying, "keep flying the plane just like you were taught in 172 school, Q-400 school, CRJ school and A-300 school..."

              However; somehow, you will disagree with the sentence above.
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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              • #82
                Originally posted by Evan View Post

                There are problems with that though. For one thing, the total loss of speeds in high-altitude turbulence results in an immediate loss of autoflight and need for manual intervention before the QRH values can be obtained. The pitch attitude prior to the disconnect could be quickly lost in that choppy, rolling transition. Therefore, it seems logical that a similar pair of broad, cruise-level-flight pitch/power targets should also be provided as a Memory Item for all weight categories above and below FL250, just to stabilize within the safe envelope for a minute or so.
                If a pilot doesn't know his airplane's typical "broad cruise pitch/power settings", no amount of memory items will save him, trust me. That guy/gal shouldn't be flying anything. I do remember sharing these with you for the 320 series (and you disagreed then, too, for some reason):

                Above FL300 2.5-3.0ANU 85% N1
                Between FL200-and FL300 2.5-3.0ANU 75% N1
                Below FL200 2.5-3.0ANU 65% N1

                2.5ANU is particularly easy because that's the first hashmark on the PFD. So, hashmark 85, hashmark 75, or hashmark 65. How much more of a memory item do you need? You will find (just like last time) that these values are within a degree or so and a few percent N1 of QRH values. Again, you're paying me to know my airplane, not my QRH.

                Comment


                • #83
                  Originally posted by ATLcrew View Post
                  Again, you're paying me to know my airplane, not my QRH.
                  I want to apologize for pondering if anything could be done differently for AF- but it's what we do. Not taking off, probably would have prevented this.

                  Aside from that, I find myself concluding there isn't much. The dude was trained, the dude probably wasn't a total idiot, the dude was screened, the dude was periodically reviewed. It sucks. We will never know why he did what he did.

                  I have no special love for the theory that he wanted the automation to give him a safe, slow airspeed (and maybe climb on top) via the full pull up...I would agree that this was inappropriate improvisation, if true. It just seems like the best? SLIGHTLY plausible explanation for his 'inexplicable' actions.

                  It's also possible that Gabby and I would not have crashed (Important disclaimer: At least not crashed in the manner in which he crashed.).

                  I think it's highly possible that I would have passed him from an HR standpoint (not that I have ANY expertise). Evan knows he would be able to screen the guy out as a bad apple for some memory/procedural/somethingorother. But would AA, Delta, WN have failed him because of something magical they do that AF does not?

                  The world is a complicated place and not everyone can be ATLcrew, unfortunately.
                  Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                  Comment


                  • #84
                    Originally posted by ATLcrew View Post
                    If a pilot doesn't know his airplane's typical "broad cruise pitch/power settings", no amount of memory items will save him, trust me. That guy/gal shouldn't be flying anything. I do remember sharing these with you for the 320 series (and you disagreed then, too, for some reason):

                    Above FL300 2.5-3.0ANU 85% N1
                    Between FL200-and FL300 2.5-3.0ANU 75% N1
                    Below FL200 2.5-3.0ANU 65% N1

                    2.5ANU is particularly easy because that's the first hashmark on the PFD. So, hashmark 85, hashmark 75, or hashmark 65. How much more of a memory item do you need? You will find (just like last time) that these values are within a degree or so and a few percent N1 of QRH values. Again, you're paying me to know my airplane, not my QRH.
                    I might have misunderstood those for A330 settings, but anyway... I'm not suggesting that any pilot doesn't know his/her aircraft's typical "broad cruise pitch/power settings". I'm suggesting that, in this scenario, the pilot needs to be trained to react by following a procedure, and that procedure consists of shutting down the AT and the FD's and setting pitch and power. It does not involve maintaining the current altitude, which is what I think Bonin was trying to do, and which I can understand might be the goal of a pilot in 'leveling off' to troubleshoot. The altimeter and the VSI will also be prompting you to do so, because they are affected by the erroneous mach data. Nor does it involve climbing above the weather system, which is also what I think Bonin was doing, with improvised pitch and power, even if the REC MAX gives you room to do so. This is the point I can't seem to get across. This is about the combination of human factors and the deceptions and stealth factors that are created by the loss of airspeeds. I want the initial, focused task to be pitch and power, using safe values known by memory. That generally is best done by training and practice on a memorized procedure for a specific failure condition, not 'do what you normally do in level flight'. If that means 'set the power at 85% and fly the first hashmark', fine, as long as that's the focus (I've already memorized that just writing this sentence). But just don't do anything else with the pitch and power until you get into the QRH. Don't improvise until you have better situational awareness, have run the written procedures and have fully gathered your wits. Don't be deceived. Don't depart level flight. Why would anyone disagree with that?

                    Bear in mind that AF447, while flying level, would have been apparently sinking (due to instrumentation error), would have been decelerating (for real) and would have been intermittently providing deadly flight guidance (which the pilot seems to have followed, perhaps trusting the flight directors over the commands of his senior FO).

                    Again, you're paying me to know my airplane, not my QRH.
                    I have to respectfully disagree with that. You are paid to safely convey passengers from point a to point b (mostly through managing automation), and to take the correct and necessary actions when things go wrong. That means knowing both normal and abnormal procedures. As I said before, I think pilots who take the responsibility seriously would study the FCOM, the QRH, accident reports, aerodynamics, meteorology and all kinds of industry literature on their own time. Just like serious professionals in other jobs do. (And I think you do this).

                    Comment


                    • #85
                      Originally posted by 3WE View Post
                      I want to apologize for pondering if anything could be done differently for AF- but it's what we do. Not taking off, probably would have prevented this.

                      Aside from that, I find myself concluding there isn't much. The dude was trained, the dude probably wasn't a total idiot, the dude was screened, the dude was periodically reviewed. It sucks. We will never know why he did what he did.
                      Are you kidding me? None of the pilots were adequately trained to handle this emergency. Read the report. That's what was so shocking about it.

                      Comment


                      • #86
                        Originally posted by Evan View Post
                        Are you kidding me? None of the pilots were adequately trained to handle this emergency. Read the report. That's what was so shocking about it.
                        Boom- that would be the crux of the matter, and I am absolutely not_kidding you.

                        You see, Mister Gabieeeeeee, might just claim that he (himself) was more than adequately trained to not crash an aerodynamically perfect aeroplanie in a FDnH configuration, with disabled pitot tubes...let's ask him.

                        "That, to me, is whats so shocking about it"

                        (I'd tell you that I claim that I (Mr. full of bologna/talk-from-my-rear 3BS) was more than adequately trained not to crash an aerodynamically perfect airplane, back in 172 school, by a procedure not all that different from what ATL described, but you would not belive me).

                        Gabieeeee: What say you? (And when did you learn this awesome skill: during Native-American-Battle-Tool-named aeroplanie training, or from reading the Book of Acronyms on www.internet.com? + much practice in MSFS?)
                        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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                        • #87
                          I said it before: In aviation it is almost forbidden to say "it will never happen to me".
                          But I am pretty confident that I would not have crashed AF, or Colgan, or Pinnacle.... Not in the way they did it at least. And I think that I more or less "proved" it with BB's unforgettable present.

                          As to where I learned it? For sure basic PPL training was a big part. Was it all? I don't think so. It SHOULD be all that it takes, but I don't think that PL training was nearly as good as it SHOULD have been.
                          But yes, PPL training taught me pulling up hard is a good way way to stall at any speed and attitude, and that step banks and slow speeds are usually correlated with pulling up.

                          But I feel that things like reading accident reports and reflecting a lot on the subject were a good complement. That's how the stall thread came to be. I don;t think it would have existed (not in the way it did) if all the knowledge I had came from the PPL training or at least from the version of the PPL training I had (both theoretical and practical). I said it before, back there in the AF thread, that for something like AF or Colgan to happen it looked to me that there had to be something wrong with their BASIC flight training. Which on the other hand would not be surprising in an era of puppy-mills. And for whatever my 1-datapoint sample is worth, I know that MY PPL training was not perfect or close,

                          --- 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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                          • #88
                            Originally posted by Gabriel View Post
                            for something like AF or Colgan to happen it looked to me that there had to be something wrong with their BASIC flight training.
                            Definitely thought-provoking, for me anyway. I see that AF claims it significantly changed its flight training program after the report on 447 was published. But to your point, just how much BASIC flight training is there in a commercial pilot program? In this era of pilot shortages, are some commercial pilots still going through a form of puppy-mill training (to use your term), and all that's changed is that the curriculum and simulator schedules have been enhanced so that they spend additional time on issues like loss of airspeed data due to pitot tube failure/disagreement. I know it's a pejorative question, but would the tragic events associated with pitot failure still have occurred if the PF had real recent tangible experience of (say) flying a 172 out of a stall in a solo test flight, feeling how the aircraft responded, listening to the pitch of the engines, feeling the change in G forces.

                            Colgan seems rather different. It's not really relevant to this thread, but perhaps we have to remind ourselves that no matter how skilled we might be in basic airmanship, fatigue is very powerful at messing up memory and decision making.

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                            • #89
                              Adjective games:

                              Originally posted by Gabriel View Post
                              ***MY PPL training was not perfect or close***
                              Thus my use of the word 'adequate'...and yeah, I actually said, "more than adequate"...thinking it was fairly accurate.
                              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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                              • #90
                                Originally posted by flashcrash View Post
                                Colgan is not really relevant to this thread, blah, blah, blah, fatigue, blah, blah, blah.
                                Neither is Pinnacle- they had no problem with stall recovery. They DID have a problem with engine restarting due to some very type-specific engine issues that were not part of private pilot training- and with the issue that stalls can cause flame outs in some jet engines.

                                On the other hand, it is still tough to hear "dude, look at the deck angle", and "our airspeed is decaying"- (DUH- we're heading towards a stall)...I have since come to believe that they simply hoped against hope to maintain altitude as ordered by ATC just for another few minutes and not generate an emergency descent and potential questions.

                                "Blah blah blah": I generally agree that fatigue may be THE factor to blame with Colgan (along with the tail-stall-training theory). These all seem to defy logic.
                                Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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