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Germanwings A320 on BCN-DUS flight crash near Nice, France

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  • Originally posted by Evan View Post
    Give me a break...

    The findings of the investigation, notably from the FDR, do not align with this new scenario:
    However, the first CVR assessment conducted by French Gendarmerie (they were not permitted to take notes hence no transcript could be produced), which became the base for the states attorney's statements in the subsequent press conference, clearly noted, that it can not be determined whether the person present in the cockpit was conscious or not.

    Sure, but the FDR clearly DOES determine that the 'person present in the cockpit' was conscious. So, that's taken care of.

    The flight was at cruise, on managed guidance, and the F/O dialed in a selected altitude target of varying amounts (clearly under psychological stress) down to the minimum setting, and then repeatedly increased the airspeed target to achieve a greater vertical speed (as this was now in OPEN DES selected guidance mode). All that selected guidance doesn't occur without a conscious person present in the cockpit. Furthermore, it was revealed during the investigation that this same 'person present in the cockpit' made similar selected guidance anomalies during the inbound flight to BCN. You might remember how chilling a revelation that was.

    This new 'alternative fact' scenario is nonsense. It will probably become very popular on parlour-talking forums.
    Yes, all these facts were are addressed in the pilot's parent's press conference, and in the successive investigation by Simon.
    Again, nothing indicates that the pilot was NOT consciously doing what very apparently he was consciously doing.

    But there are several things in there that I was not aware off and a few of them strongly called my attention (although I agree that they very unlikely will change the conclusions):
    - That the investigation and prosecutors concluded that the pilot had been hospitalized due to mental illness and was undergoing depression, when apparently there is no evidence whatsoever of that.
    - That the autopilot was simultaneously in 2 modes that are mutually exclusive, and that the pilot cannot select together even if he wants to.
    - That there is no evidence that the PIC ever entered the emergency access code, or that the FO rejected the request be flipping the switch to "lock". In particular, the CVR didn't capture the 15-seconds tone that alerts the pilot that somebody outside has entered the emergency code, to give the pilot a chance to reject the request.

    --- 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
      Yes, all these facts were are addressed in the pilot's parent's press conference, and in the successive investigation by Simon.
      Again, nothing indicates that the pilot was NOT consciously doing what very apparently he was consciously doing.

      But there are several things in there that I was not aware off and a few of them strongly called my attention (although I agree that they very unlikely will change the conclusions):
      - That the investigation and prosecutors concluded that the pilot had been hospitalized due to mental illness and was undergoing depression, when apparently there is no evidence whatsoever of that.
      - That the autopilot was simultaneously in 2 modes that are mutually exclusive, and that the pilot cannot select together even if he wants to.
      - That there is no evidence that the PIC ever entered the emergency access code, or that the FO rejected the request be flipping the switch to "lock". In particular, the CVR didn't capture the 15-seconds tone that alerts the pilot that somebody outside has entered the emergency code, to give the pilot a chance to reject the request.
      (sigh)

      You know Gabriel, this is what drives me mad about conspiracy theories: the way they selectively employ ignorance to shoehorn a theory into reality.

      To begin with, DES is an FMGC managed mode, while OP DES is a selected guidance mode. When in DES mode, the autopilot is tracking an FMGC speed target via a pitch mode (DES) and the A/T mode is SPEED/MACH. However, OP DES is a selected guidance pitch mode where the A/T mode is THR IDLE. During this incident, the A/T mode was THR IDLE.

      Originally posted by BEA Final Report
      At 9 h 30 min 53 (point  ), the selected altitude on the FCU changed in one second from 38,000 ft to 100 ft (2) . One second later, the autopilot changed to ‘‘OPEN DES’’ (3) mode and autothrust changed to ‘‘THR IDLE’’ mode. The aeroplane started to descend and both engines’ rpm decreased.
      What this theory seems to be suggesting is that the FMGC may have simultaneously commanded DES and OP DES which is not possible, since the FMGC cannot command OP DES. It should also be pointed out that the two FMGC's are operating in dual synchronous mode. Any disagreement in one FMGC would cause them to degrade to Independent mode, and that would certainly have been recorded by ACARS. Any wildly random failure in one unit is not going to occur simultaneously in the other one. Again, Airbus engineers aren't entirely stupid. They provided redundancy for unforeseeable FMGC errors.

      If it is true that the FDR recorded both modes, the most likely explanation is an error in recording the mode, not an autoflight error.

      But desperate minds grasp at their ideas by ignoring ALL of the available facts and simply choose the ones that fit their fancy. So, everything I just posted will not deter them.

      - A pilot leaves the cockpit.
      - During those few minutes, the other become instantly incapacitated, without any ability to call for help.
      - And then, the autopilot does something it has NEVER done in 30 years of operation, despite it also being logically impossible.
      - AND THEN, the door keypad fails.
      - And weirdest of all, a similar thing happened briefly on the previous flight (minus the door lock failure)...

      Yeah, right. And pass the bong dude...

      Comment


      • Originally posted by Evan View Post
        (sigh)...[rants about lists of extremely unlikely circumstances]...Yeah, right. And pass the bong dude...
        While I may concur with your conclusion, don't forget that airplane crashes are very often the result of lists of extremely unlikely circumstances.

        The fine line between a tin foil hat and accepting that some low voltage wire sparked for an unknown reason with just the right temperature and just the right fuel-air mixture, and that an impossible double autopilot fault...one can moll it over without being a nut job or needing your overly-bold dismissal.

        And it doesn't help that my Win-10 / Office 365 machine just threw a total blue screen crash either.
        Last edited by 3WE; 2017-04-05, 13:58. Reason: expeletive adjectives in the wrong places.
        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

        Comment


        • Originally posted by 3WE View Post
          airplane crashes are very often the result of extremely unlikely lists of circumstances.
          I'm fairly sure that's because industry and regulators have worked hard to ensure that crashes do not result from likely combinations of circumstances.
          Be alert! America needs more lerts.

          Eric Law

          Comment


          • Originally posted by 3WE View Post
            And it doesn't help that my Win-10 / Office 365 machine just threw a total blue screen crash either.
            Thar because you don't have two Win-10 / Office 365 machines working in sychronous dual mode, where a glitch in one would switch to the other in a fail-operational way.

            It's not HAL, it's HALS.

            Comment


            • Originally posted by Evan View Post
              Thar because you don't have two Win-10 / Office 365 machines working in sychronous dual mode, where a glitch in one would switch to the other in a fail-operational way.

              It's not HAL, it's HALS.
              Too black and white for me. I am sure that Bill Gates has error traps on top of error traps...No doubt the hell better (and hell more conservative) aeroengineers have a more failsafe system, but 'more' is a relative term. Two HALS and 'fail-operational' design is just couple of error traps strung together, isn't it?
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

              Comment


              • Originally posted by Evan View Post
                But desperate minds grasp at their ideas by ignoring ALL of the available facts and simply choose the ones that fit their fancy. So, everything I just posted will not deter them.
                I dont't think that we have desperate minds here. We do have holes, contradictions and poor investigationship. Again, closing these holes, fixing the contradictions, and being serious with some non-serious parts of the investigation (like the hospitalization part) will likely not change the conclusion, but needs to be done.

                The father of the pilot (who held the press conference raising these concerns) clearly said that he didn't know and would not speculate where closing those gaps would lead to, and that he and his family were ready to accept the the FO did it intentionally if that's the conclusion after these suspect points are reviewed and fixed. I also believe that the family of the victims deserve a serious investigation that doesn't fail to explain some basic things (two incompatible AP modes active at the same time), doesn't fabricate conclusions out of thin air (hospitalization, psychological status of the FO), and states ALL the truth (that is available), not just the part that reinforce their conclusions omitting the parts that don't (like that they have no evidence whatsoever that the PIC attempted to use the emergency code or that the FO refused access after such emergency code was entered).

                The BEA has us accustomed to poor investigations (even if the conclusions are valid). The BEA is one of the world's most important aviation accidents investigation agencies and they should behave as such, being super professional and meticulous, especially in a total air disaster like this.

                - A pilot leaves the cockpit.
                - During those few minutes, the other become instantly incapacitated, without any ability to call for help.
                - And then, the autopilot does something it has NEVER done in 30 years of operation, despite it also being logically impossible.
                - AND THEN, the door keypad fails.
                - And weirdest of all, a similar thing happened briefly on the previous flight (minus the door lock failure)...

                Yeah, right. And pass the bong dude...
                I was the first one to state this chain of independent events needing to happen in the alternate scenario. I didn't make it explicit here, but what I meant is that such a chain of events would be extremely unlikely. In the AvHerald comments section, where I posted more or less the same, I was more explicit and said that:
                1- A pilot momentarily leaving his seat for a toilet break is very frequent, happens in many (if not most) flights.
                2- A pilot becoming incapacitated is unusual, but still happens a few times per weeks worldwide.
                3- The type of AP failure required to bring down the plane in this way is unprecedented, as far as I know it never ever happened after billions and billions of flights.
                4- The keypad failure... I don't know how frequent it was, but there is data that seem to indicate that this very airplane had this problem and there is no indication in the investigation regarding whether the problem had been fixed or deferred, case in which it would be a preexisting condition and would get out of the combinatorial probability analysis (or you can leave it with a probaility of 100%).

                I also said that, with point 3 alone, the chances of this event would be as unlikely as it gets, and combined with the other events there would be nothing getting anything close to impossible. I also said that total air disasters like this are extremely rare, so many times they are the result of a very unlikely chain of events (if very likely chains of events would make plans crash it would be raining planes). I also said that, once that the extremely unlikely happened, the chances that it happened are 100%.
                What are the chances that
                - a meteorite skips you by a number of feet that can be counted with your fingers, AND
                - it happens while you are skydiving (taking into account that you are not-skydiving by large most of the times, AND
                - That this event is captured in video (taking into account that the field of view of the video is only the minority of the "all around you" field of view)

                Minimal. Almost non-existent.
                What are the chances that something like this ever happened? 100% Because it did happen.

                When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth."

                I still firmly believe that, in this case, "the impossible" is the above chain of events. But we do need to prosecutors and investigators to tie up these loose ends, because there are loose ends.

                --- 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
                  I dont't think that we have desperate minds here. We do have holes, contradictions and poor investigationship. Again, closing these holes, fixing the contradictions, and being serious with some non-serious parts of the investigation (like the hospitalization part) will likely not change the conclusion, but needs to be done.
                  Concur. Even though we already know what caused the crash.

                  (like that they have no evidence whatsoever that the PIC attempted to use the emergency code or that the FO refused access after such emergency code was entered).
                  Did they make that claim in the report? All I recall was that the PIC (presumably) was banging very hard on the cockpit door, possibly with an axe, which tends to get the attention of a conscious, selective guidance entering F/O.

                  The BEA has us accustomed to poor investigations (even if the conclusions are valid). The BEA is one of the world's most important aviation accidents investigation agencies and they should behave as such, being super professional and meticulous, especially in a total air disaster like this.
                  Concur. Even though we already know what caused the crash.

                  I was the first one to state this chain of independent events needing to happen in the alternate scenario. I didn't make it explicit here, but what I meant is that such a chain of events would be extremely unlikely. In the AvHerald comments section, where I posted more or less the same, I was more explicit and said that:
                  1- A pilot momentarily leaving his seat for a toilet break is very frequent, happens in many (if not most) flights.
                  Concur.

                  2- A pilot becoming incapacitated is unusual, but still happens a few times per weeks worldwide.
                  Yes, but how often does it happen so abruptly that the pilot cannot call for help, especially a healthy jugend like this?

                  3- The type of AP failure required to bring down the plane in this way is unprecedented, as far as I know it never ever happened after billions and billions of flights.
                  Because it can't. OP DES is not a mode available under managed FMGC guidance. It must be selected.

                  4- The keypad failure... I don't know how frequent it was, but there is data that seem to indicate that this very airplane had this problem and there is no indication in the investigation regarding whether the problem had been fixed or deferred, case in which it would be a preexisting condition and would get out of the combinatorial probability analysis (or you can leave it with a probaility of 100%).
                  It could very well have been inop for some time without the knowledge of maintenance, since it is rarely ever used.

                  I also said that, with point 3 alone, the chances of this event would be as unlikely as it gets, and combined with the other events there would be nothing getting anything close to impossible. I also said that total air disasters like this are extremely rare, so many times they are the result of a very unlikely chain of events (if very likely chains of events would make plans crash it would be raining planes). I also said that, once that the extremely unlikely happened, the chances that it happened are 100%.
                  What are the chances that
                  - a meteorite skips you by a number of feet that can be counted with your fingers, AND
                  - it happens while you are skydiving (taking into account that you are not-skydiving by large most of the times, AND
                  - That this event is captured in video (taking into account that the field of view of the video is only the minority of the "all around you" field of view)
                  These are all examples of serendipitous coincidence. The alternative theory on this crash involves known impossibilities.

                  I still firmly believe that, in this case, "the impossible" is the above chain of events. But we do need to prosecutors and investigators to tie up these loose ends, because there are loose ends.
                  If someone else is paying for it, why the hell not.

                  Look, I firmly believe that the father of this pilot (and my heart goes out to him) is the victim of some predatory lawyering and has been convinced that this theory is probable by a legal parasite who thinks it's possible to extract a 'make-it-go-away' settlement from a big airframer.

                  Of all the scenarios, that is the most probable. Why? Because it's happened before... an awful lot...

                  Comment


                  • You cannot have DES mode in pitch and THR IDLE in A/T. Thus the A/T mode confirms that the pitch mode was OP DES, tracking an FCU-selected speed target, not an FMCG calculated one.
                    I have to retract this. When the managed mode is DES but still out of altitude contraints (or repressurization), the plane can be in DES (IDLE PATH) and the A/T would be in THR mode at IDLE. Once in altitude contraint however, the A/T will be in SPEED/MACH mode. The report states that the A/T remained in IDLE for the remainder of the flight, so essentially, except for the initial idle path segment of DES, it still contradicts the idea that the AP was under managed (involuntary/unconscious pilot) rather than selected (intentional/conscious pilot) guidance.

                    Comment


                    • Originally posted by Evan View Post
                      Because it can't. OP DES is not a mode available under managed FMGC guidance. It must be selected.
                      I was being more generous: I have never heard of a case where the AP fails in a way that it changes modes by itself going from holding cruise altitude to selecting a low altitude and engaging in any descent mode towards that altitude, all by itself and while failing. It would be an interesting, active and almost intentionally evil mode of failure (HAL style).

                      --- 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
                        I was being more generous: I have never heard of a case where the AP fails in a way that it changes modes by itself going from holding cruise altitude to selecting a low altitude and engaging in any descent mode towards that altitude, all by itself and while failing. It would be an interesting, active and almost intentionally evil mode of failure (HAL style).
                        Again, I think the most likely reason for a recording of both DES and OP DES is an error/anomaly in the data recording logic. The next best thing I can come up with is this: if the F/O initiated a descent in OP DES and then (perhaps while fiddling with the speed knob under psychological stress) PRESSED rather than pulled the speed knob, I THINK that would revert the speed target to an FMGC managed one and the mode would become DES. At that point, being well below the flight plan descent profile, the pitch would adjust from an open descent to an attempt to intersect the descent profile and the A/T mode would probably become SPEED/MACH as a result.

                        The modes could never have engaged simultaneously, but perhaps this might result in a recording error that they had. At any rate, the aircraft descended at a rate consistent with OP DES and incompatible with DES, so any engagement of DES would have been momentary (speed knob pushed, then pulled).

                        (DES will engage automatically during cruise at the first waypoint with an altitude constraint in the flight plan IF the descent altitude is set in the FCU window (DES is armed). To engage it manually, you must dial in a lower altitude and press the altitude knob.)

                        Comment


                        • Originally posted by Evan View Post
                          I have to retract this. When the managed mode is DES but still out of altitude contraints (or repressurization), the plane can be in DES (IDLE PATH) and the A/T would be in THR mode at IDLE. Once in altitude contraint however, the A/T will be in SPEED/MACH mode.
                          Nice to see you actually retract something. Couple corrections. DES isn't necessarily IDLE PATH (in fact, there is no IDLE PATH mode on the 'Bus per se, but I see what you're driving at). Furthermore, I can think of a couple other cases where the A/T will be at idle, while in DES.

                          Comment


                          • Originally posted by ATLcrew View Post
                            Nice to see you actually retract something. Couple corrections. DES isn't necessarily IDLE PATH (in fact, there is no IDLE PATH mode on the 'Bus per se, but I see what you're driving at). Furthermore, I can think of a couple other cases where the A/T will be at idle, while in DES.
                            It's not a mode, it's a segment of the descent flight path under DES mode where the thrust is at IDLE. See the attachment, and feel free to retract....

                            My original point before I retracted that was that UNDER THESE CIRCUMSTANCES I would not expect any idle path segment if the mode switched to DES. The plane would be so far ahead of—and thus below—the FMGC flight plan descent profile that it would be commanding the most shallow descent path of all time to intercept it, and when you descend that gradually, you're still going to need a lot of thrust, as is SPEED/MACH, not THR IDLE.
                            Attached Files

                            Comment


                            • While not disagreeing with your point that it would be feasible albeit unlikely for all of those points to line up,

                              Originally posted by Gabriel View Post
                              What are the chances that
                              - a meteorite skips you by a number of feet that can be counted with your fingers, AND
                              - it happens while you are skydiving (taking into account that you are not-skydiving by large most of the times, AND
                              - That this event is captured in video (taking into account that the field of view of the video is only the minority of the "all around you" field of view)

                              Minimal. Almost non-existent.
                              What are the chances that something like this ever happened? 100% Because it did happen.
                              However, the above almost certainly didn't happen. Phil Plait from Bad Astronomy and others including those involved in the video eventually concluded that almost certainly it was actually a small stone that had got caught up in the parachute while it was being packed on the ground and fell out after the parachute was opened. (assuming this was the incident you were mentioning?)

                              Comment


                              • According to the BBC, Germanwings and some other German airlines are dropping the 'always 2 people in the cockpit' rule brought in after this crash, saying it has no safety benefits and may be less safe due to increasing the number of people with access to the cockpit and more predictable door opening.

                                Other European airlines are keeping the rule.

                                Source: http://www.bbc.co.uk/news/world-europe-39749803

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