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  • Originally posted by ATLcrew View Post
    (fly the blasted airplane)
    Wrong. That is broadly-applicable, fundamental cowboy improvisation.

    I think it's supposed to be something like this: NAV ADR DISAGREE ECAM83% N1 alpha prot AoA RECMAX THRUST RED ALT WTF
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

    Comment


    • Originally posted by ATLcrew View Post
      It doesn't require "perfect" anything, it requires only not doing anything stupid. I think THAT is where we actually disagree. And again, your reliance on "trained procedures and memory items" is a bit misplaced. If the biggest memory item of all (fly the blasted airplane) somehow slipped his mind, I doubt he'd remember any other. Do you really not see the point I'm trying to make?
      Yes, I see your point. it’s an obvious point that you and others have been making all along. I just think it’s a superficial understanding of what happened.

      I think he made the initial half-limit pull either to regain 300 feet of altitude or accidentally while still startled and dealing with roll (or a combination of those things). I think he then made the decision to climb to REC MAX, reasoning (imperfectly) that he wouldn’t overspeed in a climb and wouldn’t stall with full climb thrust (around 100% N1). I think he overcontrolled and things quickly got away from him and he was out of his depth because he had no upset training for this scenario. I think he then fought mentally between following the direction of his senior FO or trusting the flight directors, which had re-appeared. I think his judgment was flawed, he wasn’t thinking about drag or how close critical angle was at that altitude. I think he was not the pilot you are, and many probably aren’t. I don’t think enough has been done to prevent this from happening again.

      Comment


      • Originally posted by Evan View Post
        I just think I think he I think he reasoning (imperfectly) that he I think he I think he I think his judgment wasn’t thinking I think he I don’t think.
        I think his actions were almost inexplicable.

        I think you are welcome to think all you want.

        Unfortunately, I think that whatever you think OR whatever I think may very likely be inaccurate because apparently the WWTPTR (What Was The Pilot Thinking Recorder) was inoperative.

        I think we agree he violated some sort of memory procedure. Whether it was item one of 1. Aviate, 2. Navigate, 3. Communicate OR NAV ADR DISAGREE ECAM83% N1 alpha prot AoA RECMAX THRUST RED ALT WTF OR The yet-to-be-written Evan checklist, I think it's most likely the first.
        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

        Comment


        • I'm not a commercial pilot. For what it's worth, if there had been the "old fashioned" conventional controls the flagrant inappropriateness of his actions would have been difficult to miss.
          Another AF447 question. Does the artificial horizon still operate from a gyroscope? If so, when instruments and computer systems are giving confusing messages would it provide an independent reference for pitch?

          Comment


          • Originally posted by pegasus View Post
            I'm not a commercial pilot. For what it's worth, if there had been the "old fashioned" conventional controls the flagrant inappropriateness of his actions would have been difficult to miss.
            Another AF447 question. Does the artificial horizon still operate from a gyroscope? If so, when instruments and computer systems are giving confusing messages would it provide an independent reference for pitch?
            The attitude indicator is driven by a ring-laser gyroscope, so it isn't effected by air data anomalies. The two good references you still have are attitude and thrust level and you use these to establish an approximate safe airspeed and angle-of-attack.

            Comment


            • Originally posted by Evan View Post
              The two good references you still have are attitude and thrust level and you use these to establish an approximate safe airspeed and angle-of-attack.
              So sayeth Evan on 8/9/2019 at 19:17Z with a little dot on the end of the sentence
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

              Comment


              • Originally posted by 3WE View Post
                So sayeth Evan on 8/9/2019 at 19:17Z with a little dot on the end of the sentence
                Holy hydraulics, Batman, did he really just say that?!

                Comment


                • What we have here is LOSS OF COMMS

                  Comment


                  • Originally posted by Evan View Post
                    This is the fallacy and the sticking point. Pierre Bonin DID know how to fly an airplane.
                    There is substantial evidence that he didn't know. Not at that moment at least.

                    I believe he did what he did intentionally...
                    You mean that he intentionally pulled up a 1.5G 7000 fpm 2500 ft climb and when the plane stalled he kept "puling up all the time" (in his own words)?
                    How is that NOT contradictory with your first statement that he DID know how to fly an airplane?
                    Again, EVEN IF (which I doubt) his intention was to climb, that is NOT the way to do it.

                    No no no. I now realize that no such procedure exists for what happened to AF447 (You see, I am learning something here). What I'm advocating is a procedure for loss of autoflight and airspeed disagree at cruise-level altitude. Bonin noticed the airspeed disagree within seconds of losing the autopilot. Essentially it would go something like: LOSS OF AUTOPILOT > CROSS CHECK AIRSPEEDS > If disagree exists, PF do this, PNF go to this procedure... Currently, there doesn't seem to be any standard procedure for this scenario. Even after AF447!
                    There was a procedure then and there is one now. It is titled "UNRELIABLE SPEED INDICATION" and is triggered by an UNRELIABLE SPEED INDICATION or an ADR CHECK ECAM message.

                    It should go like this (ATL, please make the needed corrections):

                    [Sound of AP disconnect]
                    PF: I have control, troubleshoot please (and focuses on keeping the plane stable, anything not crazy will work)
                    PNF: We have ECAM messages, alternate law, protections lost, thrust lock, move thrust levers, rudder trim limit lost, use ruder with care
                    PF: Understood
                    PNF: And we have some crazy speeds indications, the 3 of them differ and are showing crazy low airspeed and are unstable and coming on and off, unreliable airspeed
                    PF: Agree, unreliable speed, safe conduct of flight is not impacted, QRH procedure for unreliable speed please.
                    PNF: Unreliable speed, got it... here it is... if safe conduct of the flight is impacted, no... to level off to troubleshoot...
                    PF: We are leveled off
                    PNF: Ok, then... flight technique, adjust pitch for the required flight path, if pitch tends to increase, airplane slow, increase thrust, if pitch tends to reduce, airplane fast, reduce thrust.
                    PF: Got it.
                    PNF: When flight path is stabilized... ok and the troubleshooting starts. Let me know when ready.
                    PF: Ok, give me a second.
                    PF: Ok, stabilized.

                    Instead it went like this:

                    [Sound of AP disconnect]
                    PF: I have control (and starts to pull up a 1.5 7000fpm 2500 ft climb)
                    [Cricket] Stall Stall
                    [Cricket] Stall Stall
                    PNF: We lost the speeds

                    --- 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 Gabriel View Post

                      There was a procedure then and there is one now. It is titled "UNRELIABLE SPEED INDICATION" and is triggered by an UNRELIABLE SPEED INDICATION or an ADR CHECK ECAM message.
                      Indeed.

                      Comment


                      • Originally posted by Gabriel View Post
                        ...It should go like this (ATL, please make the needed corrections):

                        [Sound of AP disconnect]
                        PF: I have control, troubleshoot please (and focuses on keeping the plane stable, anything not crazy will work)
                        PNF: We have ECAM messages, alternate law, protections lost, thrust lock, move thrust levers, rudder trim limit lost, use ruder with care
                        PF: Understood
                        PNF: And we have some crazy speeds indications, the 3 of them differ and are showing crazy low airspeed and are unstable and coming on and off, unreliable airspeed
                        PF: Agree, unreliable speed, safe conduct of flight is not impacted, QRH procedure for unreliable speed please.
                        PNF: Unreliable speed, got it... here it is... if safe conduct of the flight is impacted, no... to level off to troubleshoot...
                        PF: We are leveled off
                        PNF: Ok, then... flight technique, adjust pitch for the required flight path, if pitch tends to increase, airplane slow, increase thrust, if pitch tends to reduce, airplane fast, reduce thrust.
                        PF: Got it.
                        PNF: When flight path is stabilized... ok and the troubleshooting starts. Let me know when ready.
                        PF: Ok, give me a second.
                        PF: Ok, stabilized...
                        A bit of disconcurment.

                        More like this:

                        HAFDNHPF: HOLY CRAP, WHAT'S IT DOING NOW, WE'RE GOING TO DIE, EVERYTHING HAS GONE OFFLINE, THIS FBW CHEAP COMPOSITE CRACKERBOX IS GOING TO KILL US, I HAVE NO IDEA WHATS GOING ON, I LOVE YOU MRS. PF!!!!!

                        PNF: Just fly the plane...just like a 172...fly the plane...even if we're going to die, keep flying it to the end...

                        [Unknown]: Ok, the PLANE seems to be ok...bejebus, now if we can figure out this phugoid automation...I'm gonna need a minute...

                        (My version does a little better job capturing the so-called 'startle factor'.)
                        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                        Comment


                        • Originally posted by Gabriel View Post
                          There is substantial evidence that he didn't know. Not at that moment at least.


                          You mean that he intentionally pulled up a 1.5G 7000 fpm 2500 ft climb and when the plane stalled he kept "puling up all the time" (in his own words)?
                          How is that NOT contradictory with your first statement that he DID know how to fly an airplane?
                          Again, EVEN IF (which I doubt) his intention was to climb, that is NOT the way to do it.


                          There was a procedure then and there is one now. It is titled "UNRELIABLE SPEED INDICATION" and is triggered by an UNRELIABLE SPEED INDICATION or an ADR CHECK ECAM message.

                          It should go like this (ATL, please make the needed corrections):

                          [Sound of AP disconnect]
                          PF: I have control, troubleshoot please (and focuses on keeping the plane stable, anything not crazy will work)
                          PNF: We have ECAM messages, alternate law, protections lost, thrust lock, move thrust levers, rudder trim limit lost, use ruder with care
                          PF: Understood
                          PNF: And we have some crazy speeds indications, the 3 of them differ and are showing crazy low airspeed and are unstable and coming on and off, unreliable airspeed
                          PF: Agree, unreliable speed, safe conduct of flight is not impacted, QRH procedure for unreliable speed please.
                          PNF: Unreliable speed, got it... here it is... if safe conduct of the flight is impacted, no... to level off to troubleshoot...
                          PF: We are leveled off
                          PNF: Ok, then... flight technique, adjust pitch for the required flight path, if pitch tends to increase, airplane slow, increase thrust, if pitch tends to reduce, airplane fast, reduce thrust.
                          PF: Got it.
                          PNF: When flight path is stabilized... ok and the troubleshooting starts. Let me know when ready.
                          PF: Ok, give me a second.
                          PF: Ok, stabilized.

                          Instead it went like this:

                          [Sound of AP disconnect]
                          PF: I have control (and starts to pull up a 1.5 7000fpm 2500 ft climb)
                          [Cricket] Stall Stall
                          [Cricket] Stall Stall
                          PNF: We lost the speeds
                          There is no argument between us that CRM failed here and that it was a major causative factor.

                          And thank you for pointing out that a procedure exists for unreliable airspeed. Of course, I already know that.

                          But, if what ATL is telling us about the new (circa 2006) 'combined' procedure replacing the old, split procedures is still the official procedure, even after the lessons of AF447, than this what I'm taking issue with.

                          There used to be a procedure for this. If called for immediate actions to stabilize using engineering-derived pitch and power settings (5deg/CL), as well as the necessary system reconfigurations. It was included as a memory item AFAIK. It minimized the risk of pilot improvisation driven by erroneous indications and clouded judgement. Three years before the scenario of AF447 revealed itself, Airbus decided to replace it with this one:

                          Click image for larger version

Name:	uas-adr.jpg
Views:	1
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ID:	1041552

                          I can only surmise that this was done with the assumption that UAS doesn't typically occur at cruise level, FDnH phases of flight, where errors are amplified and tolerances reduced, and done without deeply understanding the human factor issues such an event creates. That is somewhat understandable in 2006, but not in the years following the lessons of AF447.

                          First of all, why are you prioritizing an ADR CHECK PROCEDURE to 'identify the faulty ADR(s) and switch it (them) off'? You do NOT want to do that! The speeds in this scenario will self-restore, typically within a minute (as they did with AF447). Secondly, it's pointless: there is nothing wrong with the ADR's. The procedure doesn't apply to this (newly revealed) failure situation. Thirdly, there is a 'fingerprint' of failures that identifies this situation. The obvious ones are the sudden loss of autoflight (cavalry charge) and Normal Law, followed by the recognition of airspeed disagreement. The pitots have become simultaneously contaminated by a temporary environmental condition that will shortly alleviate. The only task is to manually stabilize, reconfigure certain systems and to remain in stable flight for approx one minute.

                          What I'm saying is that, for this scenario, we should return to the order of the original procedure because the most important actions (and only necessary actions) are boxed in the IMMEDIATE ACTIONS (as a memory procedure) part of that procedure. No ADR CHECK PROC is needed to get things back on track (although the procedure should be run through, once everything is stable, just in case).

                          This is why I suggested to ATL that he might be misinterpreting the application of this procedure, that is for a different scenario than the one made widely known by AF447. Either that or someone higher up isn't thinking this through. If ATL is right, then his airline is lacking an appropriate procedure for an AF447 failure scenario, and nothing except sound pilot judgment and proficiency (in a situation that has been shown to degrade these things) defends the aircraft against erroneous pilot judgment and dangerous improvisation.

                          Comment


                          • Originally posted by Evan View Post
                            There used to be a procedure for this. If called for immediate actions to stabilize using engineering-derived pitch and power settings (5deg/CL), as well as the necessary system reconfigurations. It was included as a memory item AFAIK. It minimized the risk of pilot improvisation driven by erroneous indications and clouded judgement. Three years before the scenario of AF447 revealed itself, Airbus decided to replace it with this one:

                            [ATTACH=CONFIG]27177[/ATTACH]
                            Nope, THAT was the old procedure(s). Tow different procedures, one for unreliable airspeed and one for ADR check, and you had to decide which one to use depending on whether the safe conduct of the flight was impacted or not. And at some point one pointed to the other and vice versa.

                            3 years before AF it was changed to the new unified version that we discussed (which is located later in the same document) which you execute (the same procedure) for unreliable airspeed or for ADR check, and has the question about whether the safe conduct of the flight is impacted in the beginning of the procedure.

                            --- 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 Gabriel View Post
                              Nope, THAT was the old procedure(s). Tow different procedures, one for unreliable airspeed and one for ADR check, and you had to decide which one to use depending on whether the safe conduct of the flight was impacted or not. And at some point one pointed to the other and vice versa.

                              3 years before AF it was changed to the new unified version that we discussed (which is located later in the same document) which you execute (the same procedure) for unreliable airspeed or for ADR check, and has the question about whether the safe conduct of the flight is impacted in the beginning of the procedure.
                              Ah, I uploaded the wrong page. This is it:

                              Click image for larger version

Name:	uas-adr-2.jpg
Views:	1
Size:	420.0 KB
ID:	1041559

                              But please respond to the point I'm making. The red boxed items are necessary to avoid errors and deception. Meanwhile, the instruction for when the affected ADR cannot be identified (as in this case because there is no ADR fault), is to shut them all off. That's rather counterproductive, isn't it? This is why I called it absurd for the situation AF447 was in.

                              Again, I see the ADR check procedure as useful when a speed disagree is developing due to a faulty sensor or ADR, but not for a complete loss of speeds, autoflight and normal law due to ice ingestion.

                              Comment


                              • Originally posted by Evan View Post
                                Ah, I uploaded the wrong page. This is it:

                                [ATTACH=CONFIG]27184[/ATTACH]
                                Nope, that's the one that applies when the BUSS option is installed. Try again. Page 17.

                                Or here:

                                http://flightacademy.info/wp-content...-procedure.png

                                And to the point you are making, I don't even understand it, but I don't agree that these memory items are necessary to avoid errors.

                                --- 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

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