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  • 3WE
    replied
    Originally posted by Evan View Post
    Well He doesn't keep the sidestick pegged at 7000fpm/1.5G.
    But still enough to burn all excess airspeed, stall the thing and no doubt register on numerous LSSSGAs.

    And not_unlike what I did when instructors said, "Ok, let's practice stalls"

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  • Evan
    replied
    Originally posted by Gabriel View Post
    I am absolutely open to that possibility. It is one of the 2 options that he lacked said airmanship during his actively self-induced upset: Either he never had it OR he had it and suddenly lost it (the latter being totally compatible with your proposition above). But it is a FACT supported by ample evidence that he lacked it during the incident.
    Well just have to disagree on that. Having an understanding of airmanship and exhibiting airmanship are two different things. One requires only knowledge. The other requires knowledge, sound judgment, healthy situational awareness and practiced skills.

    Hmmmm. Define "actions" and "intentional". Did he intentionally pulled up a 1.5G 7000 fpm 2500 ft climb and then when the stall warning sounded intentionally pulled up actively turning an "approach to stall" to a 40+ deg AoA stall?
    I already answered this one. You are listing the consequences, not the intentions. The stall warning could have been considered spurious. As I just pointed out, he could have done all of this and leveled off at 37,000ft without stalling.

    I do see room for improvement there.
    But don't you agree that the procedure itself is wrong? Why are you wasting time trying to identify a faulty ADR when the problem isn't a faulty ADR? Where are the memory items for loss of autoflight due to unreliable airspeeds?

    When you want to climb, you don't just pull up. That's NOT how flying a plane works.
    AFAIK, you climb by increasing speed and/or AoA. The pilot assumes the thrust is already at full CL (100% N1). The pilot assumes the plane is slowly descending. If he intended to climb, why wouldn't he pull up?

    And I am focusing more in the "Bonin wasn't trained" part, not in UAS at high altitude (whit whatever procedure or technique), not in manual flight at high altitude, not in stall at high altitude...
    If he was well trained and current perhaps he could have kept his wits and reacted more calmly and measuredly.
    Absolutely. Especially if he had practiced and memorized a procedure for this.

    But the crazy unbelievable climb that he did? When was the last time he saw anything remotely close to 12+ degrees ANU in the attitude indicator at cruise altitudes, even in a climb? NEVER. When was the last time he saw 7000 fpm in a climb at any altitude, even during take-off? NEVER. When was the last time he applied 1.5G to climb, at whatever altitude, even immediately take-off, let alone cruise? NEVER. How is that justified by intentional rational improvisation using reasonable airmanship?
    Again, I don't think he intended to achieve 7000fpm of 1.5G, but when was the last time he had to do an manual emergency climb to REC MAX at cruise altitude, because I suspect that was his intent. And if it wasn't, and he intended to execute a smooth, steady climb, I think he just didn't have the skills down. He doesn't keep the sidestick pegged at 7000fpm/1.5G. He's all over the place. You really should look more closely at the sidestick plots.

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  • Gabriel
    replied
    Originally posted by Evan View Post
    - Are you open to the possibility that Pierre Bonin DID have a firm grasp of fundamental airmanship at the moment just prior to the upset?
    I am absolutely open to that possibility. It is one of the 2 options that he lacked said airmanship during his actively self-induced upset: Either he never had it OR he had it and suddenly lost it (the latter being totally compatible with your proposition above). But it is a FACT supported by ample evidence that he lacked it during the incident.

    - Are you open to the possibility that his actions might have been intentional, the result of confused situational awareness, poor aircraft handling skills at that flight level, and a prior goal to ascend to higher altitude?
    Hmmmm. Define "actions" and "intentional". Did he intentionally pulled up a 1.5G 7000 fpm 2500 ft climb and then when the stall warning sounded intentionally pulled up actively turning an "approach to stall" to a 40+ deg AoA stall?

    - Do you see how the existing combined procedure Unreliable Speeds / ADR Check is mismatched (even counterproductive) to the needs of the situation we are describing?
    I do see room for improvement there. I have not made my mind up in waht improvement though. But I am open to it.
    What I don't have confidence in is that this pilot under this circumstances would have applied ANY procedure correctly.

    - Do you therefore see the need for a procedure that IS appropriate for the situation we are describing?
    Idem as above.

    Climb is not a goal, it is a means to achieving a goal, the goal in this case being a higher flight level in smoother, uncontaminated air. The goal was achieved.
    If you want to get higher you have to climb so "climb" has to be at least related with an intermediary goal. But "climb" by itself is insufficient (as a goal or as a mean to achieve it).
    If you are driving North and want to go West, you just turn West? (and bump into a fence for not doing it in a corner or lose control for applying just 1/8 of the steering wheel travel at 100 MPH?)
    "Climb" NEEDS to be associated with performance goals. When you want to climb, you don't just pull up. That's NOT how flying a plane works. Do we need a "climb" QRH procedure with memory items?

    You see, that hinges on WHY he did what he did. If it was for lack of a clear and simple set of memorized actions to follow, then I would place a much higher faith in that pilot to follow the procedure correctly (if properly trained on it - Bonin wasn't) than to improvise incorrectly.
    And I am focusing more in the "Bonin wasn't trained" part, not in UAS at high altitude (whit whatever procedure or technique), not in manual flight at high altitude, not in stall at high altitude...
    If he was well trained and current perhaps he could have kept his wits and reacted more calmly and measuredly.

    All excessive of course, but not the 'relentless' scenario you seem to be describing.
    "Relentless" is not my word. I did use "crazy" and "unbelievable" in some vernacular fashion which is closer to "surprising" and "hard to understand if he was acting rationally".

    It was unsound reasoning, absolutely, because you don't want to leave the current flight path without airspeeds UNLESS you are following the safe targets provided in a written and memorized procedure. But, lacking such a procedure (as he was) his flawed logic (flawed, in part, by misleading indications and stealth factors, but also by a lack of training for the UAS) caused him to both improvise (climb) and overcontrol (due to a lack of manual flight experience up there).
    I understand the "improvise" justification much better than the "overcontrol". There are may ways of doing things wrong. If he had established a shallow climb forgetting to add thrust it would have still be improvising and wrong and he may very well ended up with the stall warning activating after climbing 2000 ft in this smoother way. But the crazy unbelievable climb that he did? When was the last time he saw anything remotely close to 12+ degrees ANU in the attitude indicator at cruise altitudes, even in a climb? NEVER. When was the last time he saw 7000 fpm in a climb at any altitude, even during take-off? NEVER. When was the last time he applied 1.5G to climb, at whatever altitude, even immediately take-off, let alone cruise? NEVER. How is that justified by intentional rational improvisation using reasonable airmanship? That's not enough. So maybe he was not that rational after all? Perhaps it was more "guttural"? THAT is my point.

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  • Evan
    replied
    Originally posted by Gabriel View Post
    Evan, as it happened in the past, your confirmation bias doesn't let you read what I wrote (and "read" also has more than one meaning).

    I am already tired of saying "I didn't say that" or "context please" or "But I said this other thing".
    I read your posts carefully. I don't see where I'm taking things out of context or biasing the things you are saying. The things you are saying don't seem to match with the flight recorders. But just in case I am, please just put it succinctly:

    - Are you open to the possibility that Pierre Bonin DID have a firm grasp of fundamental airmanship at the moment just prior to the upset?

    - Are you open to the possibility that his actions might have been intentional, the result of confused situational awareness, poor aircraft handling skills at that flight level, and a prior goal to ascend to higher altitude?

    - Do you see how the existing combined procedure Unreliable Speeds / ADR Check is mismatched (even counterproductive) to the needs of the situation we are describing?

    - Do you therefore see the need for a procedure that IS appropriate for the situation we are describing?


    And, finally, "climb" is not a goal, it never is, not a valid one form an airmanship point of view at least.
    Climb is not a goal, it is a means to achieving a goal, the goal in this case being a higher flight level in smoother, uncontaminated air. The goal was achieved. The plane rose to FL370 and the turbulence seemed to have abated. One of the probes had cleared. The other was about to clear. At this point the aircraft was still within the envelope, and if Bonin had simple achieved his goal and leveled off, all would have been well. But he made a second, much steeper climb order shortly after that (about 45 secs after the upset) which resulted in the stall and the complete degradation of situational awareness. The reason for the second pitch event is more mysterious to me than the initial one, but I think the flight directors played a role and I think he had just lost his confidence and his bearings at that point and his judgment was defeated at this point. The actual stall then occurs around 02h10min 54, or almost a minute after the loss of autopilot.

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  • Gabriel
    replied
    Evan, as it happened in the past, your confirmation bias doesn't let you read what I wrote (and "read" also has more than one meaning).

    I am already tired of saying "I didn't say that" or "context please" or "But I said this other thing".

    I was starting another post like that where I am replying to your points one by one and was finding myself doing the above a lot, but at this point I believe it is useless to do it yet once again.

    If you are interested in continuing the discussion with an open mind, please re-read my last few posts again (among the relevant ones, you can skip the OT ones), with an open mind, and not focusing too much in the parts for which you can find ways to be interpreted in the way you want although there are other interpretations that make more sense in the context, ignoring other parts, totally missing the
    point in others, or saying that I said something that is explicitly different than what I said.

    And, finally, "climb" is not a goal, it never is, not a valid one form an airmanship point of view at least.

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  • Evan
    replied
    Actually, maybe I can put it more succinctly:

    You all seem to be saying this was a clear case of failed fundamental airmanship and all that needs to be done is to ensure that ALL pilots have a firm grasp of that. (the little dot is a period)

    I'm saying, maybe not. Maybe this was a case of failed supplemental airmanship and we need to focus of providing better procedural (memorized) training for this scenario.

    (Keep in mind we are only dealing with the upset itself here, the first 45 secs or so. What happens after the upset is another matter, but we can prevent that by containing the upset).

    Leave a comment:


  • Evan
    replied
    Originally posted by ATLcrew View Post
    And you're willing to offer the same in return, right?
    How am I not? You all seem to be saying this was a clear case of failed fundamental airmanship and all that needs to be done is to ensure that ALL pilots have a firm grasp of that. (the little dot is a period)

    I'm saying, maybe not. Maybe this was a case of a pilot with solid fundamental airmanship but faced with a complex and deceptive scenario mixed with a bad judgment, bad intention and unpracticed skills. We have to keep an open mind.

    I am also saying, since we can't prevent such lapses of judgment and unpracticed skills where skills are rarely practiced, reliably, across the industry, we need a simple, memorized procedure with focused and easily attainable goals to minimize the opportunity for improvisation and bad judgment. These already exist for situations where 'you're fixin' to hit something', so there's precedent (not to mention the other 11 memory items).

    The only thing standing in the way of doing this is initiative, volition (will) and an open mind.

    That way, whether I am right or you are right, we're covered. Open minds do not stand in the way of open-minded initiatives.

    (And btw, the best solution to this lies in automation, but until then...)

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Evan View Post
    That is all I'm asking.
    And you're willing to offer the same in return, right?

    Leave a comment:


  • Evan
    replied
    Originally posted by Gabriel View Post
    You are distorting, to say the least, my position. That AT THE MOMENT OF THE INCIDENT he lacked a firm grasp of the most basic airmanship is a fact.
    Really? A fact?

    And the pull up was excessive (by way too much , hence the "crazy" and "unbelievable") since instants (I give you the 2 seconds) after the AP disconnect all the way from 35000 ft to 37500 ft and then all the way from there to 0 ft. That's a fact. Does that mean that he had the stick against the back stop all the time? No. I said it before. a quarter turn can be an excessive input in a steering wheel (even when it has a travel of 2 turns).
    The facts are contained in the FDR plots. The fact is, there is no sustained upward pitching command at or near the limit. The actual commands are more or less as I described already. The fact is that, over the next 45 secs, his commands were mostly pitch-up, though not always near the limit and a number of them were nose down. Obviously, these commands were excessive for the speed and altitude, but that can be attributed to a lack of practiced flight skills in those conditions. I am arguing that his intent may have been rational (though procedurally wrong and dangerous) but his actions produced results exceeding his intentions.

    Unbelievable, also means incredible (again, not only in the sense that it is not-credible), extraordinary, astonishing, remarkable, impressive, surprising, inexplicable, and beyond belief. Maybe I am meaning some of those but not others?
    'Unbelievable' means either 'exceeding what can be believed' or, in vernacular usage 'approaching the limit of what can be believed'. It doesn't really correlate to 'remarkable, impressive, surprising', although these days, when everyday speech is expressed with the rhetorical flavoring of hyperbole, who knows what value it has. 'Crazy' on the other hand...

    Better education in fundamentals, systems and etc will surely not harm.
    This is mandatory and vital education, I agree.

    Practice of manual flight in all phases of flights (including cruise) is necessary. How much? As it is required to be able to hand-fly proficiently the instant that it is required (which in turn requires doing it when it is not required).
    I also agree with this, but it has to be done in high-fidelity sims, which still might not produced the IRL results.

    I did say "do follow the procedures"?, which of course requires training in such procedures, which this crew did not have.
    Agreed, but I also find the existing Unreliable Speeds procedure to be flawed for the scenario AF447 encountered. A revision is needed.

    I've already conceded to you that the procedure may have room for improvement.
    Ok, I wasn't clear about that, but I also think that's putting it too mildly. The procedure itself is not matched to the reality of the failure scenario.

    And I proposed a more robust automation that doesn't give up so easily.
    We agree on this.

    What I said is that I don't trust that a pilot that did what Bonin did would be able to follow such a procedure remotely proficiently.
    You see, that hinges on WHY he did what he did. If it was for lack of a clear and simple set of memorized actions to follow, then I would place a much higher faith in that pilot to follow the procedure correctly (if properly trained on it - Bonin wasn't) than to improvise incorrectly.

    And you said before that he didn't have a G indicator. Bullshit. We all do. Roller-coasters would be not fun (or not scary) if we didn't have one. I don't know if you ever were subject to 1.5G, but it is VERY noticeable. The biggest normal acceleration due to maneuvering in a normal flight is immediately after liftoff, and it rarely exceeds 1.2G, and you can CLEARLY feel it. Now, 1.5G doesn't sound like too much more than 1.2G, except that it is 2.5 times as much (because the baseline is 1G, not 0G, there is a reason why 1G is non-accelerated flight). You can't miss it.
    I'm sure he felt it and probably felt that it was excessive. That is probably why the control inputs occillate. However the 1.5G moment was immediately followed by a negative G moment and so on. The actual acceleration at the time of the stall warning, prior to the aircraft leaving the envelope, was slightly less than 1G. It reached a peak of about 1.15G after that. Some of that acceleration is also due to turbulence. All excessive of course, but not the 'relentless' scenario you seem to be describing.

    Let me give you a counter example. Many years ago, an MD-80 was taking off from Detroit with flaps and slats up (unknown to the pilots). The take-off configuration warning didn't sound. The plane struggled to lift off (but did it) and then struggled even more to climb. The stick-shaker activated at about the moment of lift off and shortly later the stall aural warning also activated (a triple buzzer and Miss Douglas saying "stall"). How did the pilot react? He reduced the AoA until the aural warning stopped, then pulled back again until it started to sound, and kept repeating that, modulating the elevator around the onset of the aural stall warning, and he was very skillful at doing that and accomplishing his goal of keeping the AoA very close to the max lift AoA. They hit a light pole in a parking lot and crashed. All died except for one little girl that "unbelievably" survived, nobody understands what. The investigators believe that the pilots suspected a windshear and were flying the windshear procedure, which called to do exactly what the pilots did with one caveat: they should have done what they did around the onset of the stickshaker, not the stall aural warning. Interviewing pilots of the airline (including instructors), there was a "common knowledge" (but wrong) that, even what they knew what the procedure said, it was ok to pull up using the aural warning as the limit if needed, instead of the stickshaker. The stickshaker is a stall proximity warning, the aural warning instead is a critical AoA warning and it is intended to let the pilot know that if he doesn't lower the nose and the AoA deteriorates any further, the plane will lower it by itself (stick-pusher). The logic was that the aural warning limit would give you the maximum lift, which is only partially correct. What it will give you is the maximum lift COEFFICIENT, but if you can trade those couple of degrees between the aural and the stickhaker warnings for just 10 knots of extra speed, the increase in lift do to the higher speed (squared) will be significantly higher than the increase in lift coefficient in a part of the curve where the slope is flattening anyway. But while there is little difference in the lift coefficient between between the 2 angles of attack, the difference in drag is huge and, worse than that, it destroys you roll handling qualities: The ailerons become much less effective which requires much greater inputs to control which in turn means that the roll spoilers will have large deflections during significant portions of the flight which will, again, increase drag, and you will need to be correcting roll all the time because it will aslo kill the roll damping so it will be almost impossible to keep it level, and you will find yourself correcting to one side and the other all the time, which in turn means that the lift vector will be pointing partially sideways (instead of fully up) during good portions of the flight. The NTSB concluded that if they had used the stickshaker as their pull-up goal, they would have accelerated more, they would have not rolled (or not as much), they would not have needed to use so much aileron and roll spoiler inputs, and they would have cleared the light pole by more than 100 ft.

    Was there a problem with the fundamentals there? You bet it!!! Just read what I put above. The pilots didn't know it!!! Not even the instructors!!! And it is still a problem today. Some 5 years ago I had an instructor telling me that it was ok to have the stall warning on all the time while doing spiral descents. That the extra AoA and extra lift coefficient that it is available after the first indication of stall is usable (because you can still extract lift from there) is a myth of the same type than that you can't break a plane from aerodynamic forces when flying below Va (maneuver speed), which is a myth that the aviation community at large (me included) shared until the AA A-300 accident proved all us wrong.

    But the real point I wanted to make with this counter example is that, this could have been explained to pilots, during sim practices (where I guess they followed the correct procedure or they should have failed the checkride) it could have been reinforced what NOT to do, especially since the instructors knew about this myth (except that they didn't think it was a myth). These pilot had a performance goal in mind: full thrust, modulate the elevator around one specific target AoA, use ailerons to bring and try to keep the wings level. And they executed against this goal superbly. I am super-confident that if they had had the right goal in mind (all the same except at the stickshaker AoA instead of the aural stall AoA), they would also have executed it perfectly... and everybody would have lived (and perhaps nobody, except these 2 pilots, would have ever learned that the incident even existed).
    But this just reinforces my point that memorized procedures sometimes need to be scenario-specific rather than generalized. The existing procedure was fine (and safer) if there was altitude to give, but in close ground-proximity, a different procedure and target was needed. This is exactly what I am talking about when I say there needs to be a different memory procedure (learned training) specific to the AF447 scenario.

    What was Bonin's goal again and how well did he execute against his own goal? I don't have any reason to believe that he would have executed any better had he had the right goal in mind.
    Of course we can only speculate but, in speculating, we can foresee the possible goals of future pilots in this scenario. I think he reasoned that the turbulence and atmospheric conditions had knocked out the autopilot and his goal was to climb to smoother air and re-establish autopilot. It was unsound reasoning, absolutely, because you don't want to leave the current flight path without airspeeds UNLESS you are following the safe targets provided in a written and memorized procedure. But, lacking such a procedure (as he was) his flawed logic (flawed, in part, by misleading indications and stealth factors, but also by a lack of training for the UAS) caused him to both improvise (climb) and overcontrol (due to a lack of manual flight experience up there).

    If he had the right, procedural goal in mind, even if he overcontrolled in trying to achieve it, he would have been able to concentrate his efforts on it and would have most likely remained in the safe envelope during that critical minute.

    You are asking me for an open mind. Ok.
    That is all I'm asking.

    Leave a comment:


  • 3WE
    replied
    Originally posted by Evan View Post
    a stalwart refusal to consider how the sound mind can be misled into doing seemingly unsound things.
    Remember, the 'sound mind' DEVIATED from just about every procedure ever written except for A) Trees ahead, B) Mountain Ahead, C) Aeroplanie ahead and lower or trending lower, D) Airport fence ahead and E) School bus full of nun's ahead.

    So you propose a new one.

    As is often said, doing the same thing over and over and expecting a different result is kind of insane.

    Leave a comment:


  • Gabriel
    replied
    Originally posted by ATLcrew View Post
    Oh, I don't think I'm ready for El Cid just yet.
    Don't worry. Neither am I, or the vast majority of currently-alive Spanish-speaking persons.

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Gabriel View Post
    Wow, reading not only in Spanish but in medieval Spanish!!!
    Try The Cid the next time. That will be fun (or not).

    By the way, here, use it for copy-paste: ń
    Oh, I don't think I'm ready for El Cid just yet. Cervantes wrote in such a plain, beautiful language that even archaic words aren't much of an obstacle, it's just that my Spanish in general is still not where it needs to be. I have had a Madrid-born F/O read Don Quixote out loud with a somewhat overly exaggerated Castilian lithp (cabetha, abrathame, corathon, murthielago etc) much to my enjoyment.

    Leave a comment:


  • Gabriel
    replied
    Originally posted by ATLcrew View Post
    Not exactly.
    Ha! The understatement of the week.

    Leave a comment:


  • ATLcrew
    replied
    Originally posted by Evan View Post
    Are you suggesting that Pierre Bonin suffered from covert bouts of madness?
    Not exactly.

    Leave a comment:


  • Evan
    replied
    Originally posted by ATLcrew View Post
    I hope y'all enjoyed this brief literary distraction.
    All very nice ATL and impressive that you are able to read it without translation, but I am left to wonder why you are dragging Cervantes into this. Are you suggesting that Pierre Bonin suffered from covert bouts of madness? I see the resultant madness of his actions, but I also see how a rational mind, in that situation, could make those errors. I think ascribing madness to his actions is a theory of convenience, lazy theoretics, if you will. The official report, which was anything but lazy in its analysis, did not suggest that Bonin was in any way ‘mad’ prior to his actions.

    Gabriel and others have described his actions as crazy, but I see that as a stalwart refusal to consider how the sound mind can be misled into doing seemingly unsound things.

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