Originally posted by Evan
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Originally posted by 3WE View PostNo, and listen carefully- we object to cowboy improvisation that goes against "all" logic and fundamentals and procedures.
Written and memorized procedures are reliably sound. They defend against deceiving things.
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Originally posted by Evan View PostImprovisation never goes against all logic, except when it does. The question is: is the logic sound? The next question is: Is there something deceiving behind the logic?
Written and memorized procedures are reliably sound. They defend against deceiving things, except when they don't.Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
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Originally posted by Evan View PostOk, you'll have to please explain to me how your logic tells you to do one thing and you do the opposite.
I can say "1+ adverb = salty pressure" and call it Maths, grammar, cooking and Physics, just not sound at that.
For me the real question is still, what kind of procedure, memory item or whatever would have prevented the irrational and unbelievable crazy (relentless, 3we would say) pull up that the PF executed the instant the AP disconnected before anybody had any chance to identify remote idea of what was going (which is a pre-requisite for what procedure or memory items to invoke)?
What was the "logic" that triggered a 1.5G 7000fpm 2500ft climb and then a relentless pull up with the stall warning sounding uninterruptedly during more than 30 seconds and then intermittently with the plane pointing 10 degrees nose up while falling 10000 fpm?
I'll tell you what logic: an irrational, ignorant, illogical logic.
--- 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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Originally posted by Evan View PostOk, you'll have to please explain to me how your logic tells you to do one thing and you do the opposite.
But...it happened...Would you like to explain why that happened? I've offered some why's but do not defend them very strongly.Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
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Originally posted by Gabriel View Post(relentless, 3we would say)
I find that to be the best adjective for the sake of brevity and clarity.
We needed something to contrast with aggressive, but carefully measured with critical attention to the stall situation.
It's possible it's not a perfect description, but...Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
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Originally posted by Gabriel View PostWe are falling int semantics again. Is a flawed logic (let's say in illogical logic) still logic?
For me the real question is still, what kind of procedure, memory item or whatever would have prevented the irrational and unbelievable crazy (relentless, 3we would say) pull up that the PF executed the instant the AP disconnected before anybody had any chance to identify remote idea of what was going (which is a pre-requisite for what procedure or memory items to invoke)?
What was the "logic" that triggered a 1.5G 7000fpm 2500ft climb and then a relentless pull up with the stall warning sounding uninterruptedly during more than 30 seconds and then intermittently with the plane pointing 10 degrees nose up while falling 10000 fpm?
I'll tell you what logic: an irrational, ignorant, illogical logic.
That is hardly what you call pulling up 'relentlessly'. There was plenty of relenting. If we are going to ever understand what happened here, we have to stop using that word.
The potential logic:
- I am descending and need to regain altitude (logic driven by deceptive indications).
- I am penetrating a massive storm and the turbulence has just knocked off the autopilot. I need to climb to smoother air immediately (logic driven by mental imperatives).
- The stall warnings are erroneous because the speeds are erroneous (bad logic, but understandable if you havent read the procedure).
- I am nowhere near critical AoA at 5° pitch (bad logic, but understandable if you haven't been trained on high-altitude approach to stall).
- I can safely fly 10° of pitch with full climb power (logic based on false assumption, due to stealth factor and lack of high-altitude manual flight training).
- The flight directors are back. That means they have restored and I should follow them (he more or less did follow them).
At this point he reached about 12° nose-up pitch and then began about 45 secs of pitch reduction back to 6°. By then, however, he has lost his SA and is out of his depth, his logic is entirely disoriented, a place we never want pilots to arrive at. From here, logic goes anywhere, including pulling up into a 17° pitch-induced stall.
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Originally posted by Evan View PostThat is hardly what you call pulling up 'relentlessly'. There was plenty of relenting.
That being said, did the stall ever stop for the whole 37,000 feet?Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
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Originally posted by Evan View PostAre you being Socratic? All intentional actions are driven by logic. Logic can be quite flawed but it is still logic, so no intentional act can "go against all logic".
If I say "Some animals eat grass, my cat is some animal, therefore it eats grass and I will feed it with grass", is that voluntary act logical?
And perhaps most importantly... Are you sure that the pilot really intended (i.e. has the intention, since you are reducing the scope only to intentional acts) to pull a 1.5G 7000 FPM 2500 ft climb the moment that the AP disconnected?
Logic can certainly be taught and instilled. If his trained logic was "follow the memorized procedure (assuming one exists) unless it is dangerous to do so (cuz you're fixin' to hit something), then there would be no danger of flawed, improvisation logic ruining the moment.
First of all, I have to insist that we stick to the facts. The PF did nothing 'the instant the AP disconnected'. One second later he applied a modest nose up input (while rolling to the limit stops) and it remained modest for about one second. Only then did he make a more pronounced nose-up input to about half the stick limit, followed one second later by a reduced nose-up input, followed by a slightly more than half-limit nose-up input of about one second followed by a sharp reductionand then a gradual reduction to about 1/8 nose-up limit over the next two seconds, followed over the next four seconds by a series of input variations between 3/4 and 1/8 nose-up limit, followed by a steady return to neutral and a momentary nose-down input, followed by another quick nose-up input to about 1/2 limit, followed by a quick return to neutral and then two nose-down inputs. At this point the pitch, which had been steadily increasing, stopped increasing and then actually reduced slightly before very gradually increasing as his stick commands were now varying between 1/4 nose-up and 1/8 nose down.
That is hardly what you call pulling up 'relentlessly'. There was plenty of relenting. If we are going to ever understand what happened here, we have to stop using that word.
The potential logic:
- I am descending and need to regain altitude (logic driven by deceptive indications).
- I am penetrating a massive storm and the turbulence has just knocked off the autopilot. I need to climb to smoother air immediately (logic driven by mental imperatives).
- The stall warnings are erroneous because the speeds are erroneous (bad logic, but understandable if you havent read the procedure).
- I am nowhere near critical AoA at 5° pitch (bad logic, but understandable if you haven't been trained on high-altitude approach to stall).
- I can safely fly 10° of pitch with full climb power (logic based on false assumption, due to stealth factor and lack of high-altitude manual flight training).
- The flight directors are back. That means they have restored and I should follow them (he more or less did follow them).
At this point he reached about 12° nose-up pitch and then began about 45 secs of pitch reduction back to 6°. By then, however, he has lost his SA and is out of his depth, his logic is entirely disoriented, a place we never want pilots to arrive at. From here, logic goes anywhere, including pulling up into a 17° pitch-induced stall.
A 1.5G pull-up is excessive in any non-life-or-death situation.
A 7000 fpm climb is excessive in any non-life-or-death situation (and then not sustainable for very long).
Pulling up in response to a stall warning is NEVER the right reaction, even if you think that the stall warning is erroneous. Why did he pull up in response to the stallw arning at the top of the climb?
I think you are putting too much rationale into the pilots actions that I believe were more irrational, and hence less intentional, than what you think.
None of us will be able to prove it because the MTR (mind thoughts recorder) was not invented yet.
--- 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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Originally posted by 3WE View PostThat being said, did the stall ever stop for the whole 37,000 feet?
--- 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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Originally posted by Gabriel View PostAgain, that depends on what you call "logic". Are logical fallacies still "logical"?
If I say "Some animals eat grass, my cct is some animal, therefore it eats grass and I will feed it with grass", is that voluntary act logical?
And perhaps most importantly... Are you sure that the pilot really intended (i.e. has the intention, since you are reducing the scope only to intentional acts) to pull a 1.5G 7000 FPM 2500 ft climb the moment that the AP disconnected?
If you really believe that, I am out of the discussion.
A quarter turn of the steering wheel in your car can be relentless if you are going 100 MPH.
A 1.5G pull-up is excessive in any non-life-or-death situation.
A 7000 fpm climb is excessive in any non-life-or-death situation (and then not sustainable for very long).
Pulling up in response to a stall warning is NEVER the right reaction, even if you think that the stall warning is erroneous. Why did he pull up in response to the stallw arning at the top of the climb?
The bottom line here, really, is that you can choose to try to understand this from the point of view of startle factor, deceiving indications and flawed logic (flawed judgment) driving intentional acts executed with unpracticed skills or you can choose to never understand it at all and just write it off as 'unthinkable acts of poor airmanship'. But only the former (along with engineering improvements) can bring about any meaningful changes to prevent it from recurring.
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Originally posted by Gabriel View PostYes, it sounded continously "only" for some 30 seconds. Then, with the pitots working again, the AOA became so high that the (now reliable) airspeed was erroneously too low, below the lower threshold to consider the AoA measurement "reliable". SO the stall warning became intermittent for the rest of the fall as the plane's speed oscillated into and out of that threshold.Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
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For the Nth time, if you want to put it as ït as the inputs, not the consequences", then I would not trust this pilot (in the mental state that he had in the moment) to follow any memory items or procedure. Because the procedure would not have been "pull the stick 1/8 back", it would be based on RESULTANT PERFORMANCE or CONSEQUENCES.
And I don't agree with your false dilemma of you are either with me or shut up. Sorry, there are other choices. There are other ways than this could happen other than "intentional acts based on logic", which I will not repeat anymore.
--- 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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Originally posted by 3WE View PostPlease reread what I wrote, and answer the question I actually asked.
--- 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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