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Breaking news: Ethiopian Airlines flight has crashed on way to Nairobi

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  • Originally posted by BoeingBobby View Post
    Do you see ANYTHING in that NEWSPAPER article that says the word trim anyware?
    No, I do not actually see the term 'trim' used there. What is your point...?

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    • it would be nice if Boeing released a video explaining why their planes cant be hacked. Until that video, I aint flying on planes again.

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      • Originally posted by BoeingBobby View Post
        Brian, I am surprised that you would say that. In my opinion, and after a lengthy conversation with a friend that is a Captain one, I would personally have no problem getting on a MAX. As long as it was being operated by a competent crew.
        And therein lies the problem. Apart from giving the cockpit crew a preflight written test on the features of MCAS and recovery procedures from a problem how are we to know that they are competent in recovering from a runaway trim on a -800 MAX ?
        If it 'ain't broken........ Don't try to mend it !

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        • Originally posted by Evan View Post
          No, I do not actually see the term 'trim' used there. What is your point...?
          Remember something about the runaway trIm procedure?

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          • Originally posted by BoeingBobby View Post
            Remember something about the runaway trIm procedure?
            The procedure, yes. Trim switches up. Cutoff switches to off. Also, I've seen 'grab the trim wheel' on the older stuff.

            As I said to Gabriel though, I am not talking about the procedure. I'm talking about the way the control column cuts off the electric nose-down trim movement when the pilot pulls up instinctively against a sudden nose-down event. Except on the MAX when it doesn't...

            I'm talking about instinctive reaction and the difference between the NG and the -MAX of the flight surface response to that instinctive reaction .

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            • Originally posted by BoeingBobby View Post
              Do you see ANYTHING in that NEWSPAPER article that says the word trim anyware?
              I do. When I read "stabilizer movement" I see the word "trim".

              --- 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 Post
                The procedure, yes. Trim switches up. Cutoff switches to off. Also, I've seen 'grab the trim wheel' on the older stuff.

                As I said to Gabriel though, I am not talking about the procedure. I'm talking about the way the control column cuts off the electric nose-down trim movement when the pilot pulls up instinctively against a sudden nose-down event. Except on the MAX when it doesn't...

                I'm talking about instinctive reaction and the difference between the NG and the -MAX of the flight surface response to that instinctive reaction .
                What instinctive reaction? How can you have an instinctive reaction if it is neither something we as a species evolved to react instinctively nor something that is performed until it becomes instinct? Add (I hope) it is neither something that is taught and processed intellectually by pilots to become what I think I called an "intellectual automated response" back then (stick-shaker reaction in the 747).

                Now, if you mean that a pilot may instinctively react to a nose-down force beyond expectations with pulling back on the yoke, ok, I can get that. But if you never experienced that before, what difference does it make that the NG had it and now the MAX doesn't? We can argue if it is a feature that is needed in itself and then blaming Boeing for not putting this feature in the MAX, but I don't see where if the all the previous 5000 versions of all the Boeing planes had this feature for 2 centuries or not would make a difference.

                --- 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 Post
                  What instinctive reaction? How can you have an instinctive reaction...
                  Now, if you mean that a pilot may instinctively react to a nose-down force beyond expectations with pulling back on the yoke, ok, I can get that.
                  That is what I mean.

                  But if you never experienced that before, what difference does it make that the NG had it and now the MAX doesn't?
                  Experienced what before? An nose-down pitch excursion? Or a trim runaway? I'm guessing a lot of experienced pilots have experienced one of those things. I'm hoping a lot of them have also trained for both of them in the sim. So now we have a control response difference, where, if you happened to notice that the trim could be stopped by pulling aft in the past, you might be expecting that same thing to happen in the MAX. Maybe many pilots have never experienced such things. Who knows? Shall we take a survey? Or shall we err on the side of safety, you know, like we used to...

                  And by the way, Boeing had a very good reason to have that function there in the first place and keep it there for five decades (or more). The ONLY reason they removed it on the MAX was because they painted themselves into a corner.

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                  • Originally posted by Evan View Post
                    Do you mean negative training? Because that is what training for an MCAS runaway on an NG simulator amounts too. The fact is, Boeing rushed the MAX to the degree that not a single MAX sim was available at the time it went into service. The more we learn about the PHYSICAL reaction differences of these two aircraft to trim runaway, the more obvious it is that a MAX sim session is needed for safe compliance. The problem began with training pilots on an ipad and will not be solved by re-training pilots on an ipad.
                    I will ignore the debate on the technical aspects of the training. Boeing issued a safety bulletin to all MAX airlines instructing them to have the pilots review the training on how to switch it off. The fact that even you (a non-pilot) seem to know more than the pilot flying Ethiopian is the problem here. This was a known issue. Airlines were instructed to review training around this exact scenario. It is looking like Ethiopian didn't seem to take that seriously enough and now we have another planeload of people that died. These particular deaths are not on Boeing alone.

                    Ethiopia owns the investigation right now. How much you want to bet we never see the transcript of the CVR?

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                    • Originally posted by Schwartz View Post
                      I will ignore the debate on the technical aspects of the training. Boeing issued a safety bulletin to all MAX airlines instructing them to have the pilots review the training on how to switch it off. The fact that even you (a non-pilot) seem to know more than the pilot flying Ethiopian is the problem here.
                      Sometimes this forum is like some sort of sitcom where I express key points of an argument and then they just evaporate and we start over again.

                      Your conclusion is that, because a pilot failed to quickly recognize the complex, incredibly disorienting and heretofore unknown upset situation that he suddenly found himself in--sorry--that Boeing thrust him into--he must not have got that memo about what it probably was. Your conclusion is based on the notion that, because BoeingBobby, Gabriel and most every other pilot in the universe is supremely confident that they would have done better, that this is somehow even remotely true. Meanwhile, we have a trove of data from stacks of previous accident reports going back many years that strongly contradict that assumption, revealing instead how such situations can have a tremendously deleterious effect on human situational awareness and cognitive performance. And all that emphasis by disciplined think tanks like the NTSB on the prime importance of doing everything practical to avoid placing pilots in such upset situations is just like so many dogs barking, because all we should ever need is a memo and a bit of iPad Powerpoint reminders to make flying perfectly safe again.

                      The fact that this same scenario probably took a second batch of lives sort of proves my point. Hubris isn't working. Depending on pilot awareness and proficiency as the ONLY redundancy in this bewildering scenario, memo or not, is not going to cut it across the industry. It would be nice if we could all just accept that humiliating fact and move on. Pilots are just vulnerable human beings. There, I said it.

                      Comment


                      • Originally posted by Evan View Post
                        Experienced what before? An nose-down pitch excursion? Or a trim runaway? I'm guessing a lot of experienced pilots have experienced one of those things. I'm hoping a lot of them have also trained for both of them in the sim. So now we have a control response difference, where, if you happened to notice that the trim could be stopped by pulling aft in the past, you might be expecting that same thing to happen in the MAX. Maybe many pilots have never experienced such things.
                        When you say a nose-down pitch excursion you mean with or without trim input? Because other than a trim runaway (including MCAS failure), the nose-down trim input can be caused y AP input (so they are not in manual flight and pulling the control column hard enough will disconnect the AP, not just the AP's input on the trim) or pilot input (then you have a pilot trimming down and pulling up at the same time, which I will argue is NOT normal).

                        Now, if you mean a nose-down pitch excursion during manual flight (for example, due to turbulence or due to the pilot not-flying accidentally kicking the control column), then yes, I will concede that pullin back on the yoke is a natural reaction to that. But I don't get how that will lead you "to notice that the trim could be stopped by pulling aft".

                        Oh, and by the way, if you pull back and feel that you need to keep an unusual strong pull back force to keep the nose where you want it, do you know what one thing IS (or should be) very instinctive? To apply nose-up trim because, well, that's that the trim is for and that is how it is normally used for in manual flight: to cancel stick forces.

                        And by the way 2, in manual flight, the MCAS will not cause a sudden nose-down pitch excursion. Rather, a slow and progressive trim down. With 2 big black and white wheels spinning next to your knee and making a lot of noise.

                        Again, I don't think at all that the DIFFERENCE between the NG and the MAX regarding what happens with the trim when you move the control column is a significant safety risk that would be a contributing factor in these accidents. The FACT that the control column doesn't stop the MCAS? Maybe, but that's independent of how it worked on the NG. The combination of the trim runaway with a stall warning and a speed disagree can be a factor too, overloading the pilots. As well as the fact that the MCAS stops for 5 seconds after manual trim input and then starts commanding trim again (which is very different from what would expect a trim runaway to behave).

                        The fact that this happened in daylight VFR and after the Lion Air crash makes it less understandable. At what point do you stop pulling up and applying nose up trim when you see the nose going down and the Earth becoming bigger? And nothing was learned from the Lion Air crash? I still hope that there was something else, something quite different in the Ethiopian crash. Something for which the lessons learned in the Lion Air crash were not enough.

                        --- 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


                        • Originally posted by Schwartz View Post
                          I will ignore the debate on the technical aspects of the training. Boeing issued a safety bulletin to all MAX airlines instructing them to have the pilots review the training on how to switch it off. The fact that even you (a non-pilot) seem to know more than the pilot flying Ethiopian is the problem here. This was a known issue. Airlines were instructed to review training around this exact scenario. It is looking like Ethiopian didn't seem to take that seriously enough and now we have another planeload of people that died. These particular deaths are not on Boeing alone.
                          I totally agree with you but I will go one step farther by not letting the pilots off the hook. You are flying the new Boeing 737 MAX, this same plane had just a terrible fatal crash where some systems were implicated, and you don;t go and learn all that you can about that, unless the airline spoon-feeds you (which yes, the airline should do)? Don't these pilots have internet and like 10 free days per month, apart from vacation?

                          --- 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


                          • Originally posted by Evan View Post
                            Sometimes this forum is like some sort of sitcom where I express key points of an argument and then they just evaporate and we start over again.

                            Your conclusion is that, because a pilot failed to quickly recognize the complex, incredibly disorienting and heretofore unknown upset situation that he suddenly found himself in--sorry--that Boeing thrust him into--he must not have got that memo about what it probably was. Your conclusion is based on the notion that, because BoeingBobby, Gabriel and most every other pilot in the universe is supremely confident that they would have done better, that this is somehow even remotely true. Meanwhile, we have a trove of data from stacks of previous accident reports going back many years that strongly contradict that assumption, revealing instead how such situations can have a tremendously deleterious effect on human situational awareness and cognitive performance. And all that emphasis by disciplined think tanks like the NTSB on the prime importance of doing everything practical to avoid placing pilots in such upset situations is just like so many dogs barking, because all we should ever need is a memo and a bit of iPad Powerpoint reminders to make flying perfectly safe again.

                            The fact that this same scenario probably took a second batch of lives sort of proves my point. Hubris isn't working. Depending on pilot awareness and proficiency as the ONLY redundancy in this bewildering scenario, memo or not, is not going to cut it across the industry. It would be nice if we could all just accept that humiliating fact and move on. Pilots are just vulnerable human beings. There, I said it.
                            I am sure that there are a LOT of good pilots that would not have fallen in the same trap than the Lion Air fell (which we still don't know if it is what happened to Ethiopian). Not before the Lion Air crash (the crew of the previous flight is an example) but even less after the facts surrounding the Lion Air crash became known. Perhaps we should improve pilot screening. Things like IQ, performing under pressure, and why not enough interest in your profession, the airplane you fly, your life, and the life of you passengers, that you go keep yourself very well informed of the safety vulnerabilities of your plane with or without the airline's intervention. And then a similar screening for the airlines.

                            --- 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


                            • Article in UK Daily Telegraph:

                              “After this horrific Lion Air accident, you’d think that everyone flying this airplane would know that’s how you turn this off,” said Steve Wallace, the former director of the US Federal Aviation Administration’s accident investigation branch. The combination of factors required to bring down a plane in these circumstances suggests other issues may also have occurred in the Ethiopia crash, said Jeffrey Guzzetti, who also directed accident investigations at FAA and is now a consultant. “It’s simply implausible that this MCAS deficiency by itself can down a modern jetliner with a trained crew”.

                              Comment


                              • Originally posted by Gabriel View Post
                                Oh, and by the way, if you pull back and feel that you need to keep an unusual strong pull back force to keep the nose where you want it, do you know what one thing IS (or should be) very instinctive? To apply nose-up trim because, well, that's that the trim is for and that is how it is normally used for in manual flight: to cancel stick forces.
                                Yes, as the first thoughtful action after your intial reflex action to pull back on the column, which has cancelled the nose-down trim, unless it's a MAX, in which case the trim is still increasing against you. How many seconds does it take for your awareness to kick in and your pitch trim input to begin? How much further has the trim progressed against you during that time? How much larger is the resulting upset? That is the difference between these two types.

                                And by the way 2, in manual flight, the MCAS will not cause a sudden nose-down pitch excursion. Rather, a slow and progressive trim down. With 2 big black and white wheels spinning next to your knee and making a lot of noise.
                                How certain are you about that? I've read that a trim change of 2.5 deg over 10 seconds at the speeds we are talking about can produce a rather abrupt and rapid nose-down effect.

                                Again, I don't think at all that the DIFFERENCE between the NG and the MAX regarding what happens with the trim when you move the control column is a significant safety risk that would be a contributing factor in these accidents.
                                It might be a contributing factor in confusing situational awareness but the main reason I've brought this up is that it provides rationale for a new sim requirement rather than an iPad or a desktop training aid. When the aircraft's functional responses to a reflex control input change to this degree, I think that triggers a new sim.

                                I am sure that there are a LOT of good pilots that would not have fallen in the same trap than the Lion Air fell [into]...
                                There probably are. How does that suffice for safety across the industry? I also disagree that any pilot can know whether they would have performed to their own expectations here. There is just too much evidence gathered over the years conflicting with that. I think hubris is a necessary thing for people whose job requires them to risk their lives on a regular basis. They need to have complete confidence in themselves. That's fine. But the engineers and the regulators who certify airplanes must think otherwise for aviation safety to improve.

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