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  • #61
    Originally posted by ATLcrew View Post
    Affirmative. Even if we're in a gentle descent, that's still FDnH.
    Can we all agree that the definition of "fat dumb and happy" is "matching and mashing to put the nose back where is was" whilst contending with turbulence and roll in manual flight after a sudden loss of autoflight, the loss of airspeeds and an urgently developing failure cascade?

    Comment


    • #62
      Originally posted by Evan View Post
      Can we all agree that the definition of "fat dumb and happy" is "matching and mashing to put the nose back where is was" whilst contending with turbulence and roll in manual flight after a sudden loss of autoflight, the loss of airspeeds and an urgently developing failure cascade?
      At least in the short term, sure.

      How sustainable is 5deg and CLB in the long term starting from 35000ft ISA+20?

      A simple calculation tells me that they would have had an initial climb of 2800 fpm. The speed was going to go down.

      --- 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


      • #63
        Originally posted by Gabriel View Post
        At least in the short term, sure.

        How sustainable is 5deg and CLB in the long term starting from 35000ft ISA+20?

        A simple calculation tells me that they would have had an initial climb of 2800 fpm. The speed was going to go down.
        5 deg and climb is the memorized part, the stabilizing part, which only needs to be sustained for a brief period of time while the more appropriate values are obtained from the QRH. But you know this...
        Also, the QRH procedure includes getting the autothrust out of thrust lock and actually setting it at full climb power. And actually turning off the flight directors that were intermittantly giving the pilots very bad direction.

        Seriously, there was nothing fat dumb or happy about what AF447 fell into and the situation was absolutely impacting the safe conduct of the flight. There was no justification there for skipping the memory items and going to an ADR Check Procedure. I mean, that's absurd. Again, where is this resistance to a safe, practiced and memorized procedure coming from?

        Comment


        • #64
          Originally posted by Evan View Post
          Seriously, there was nothing fat dumb or happy about what AF447 fell into and the situation was absolutely impacting the safe conduct of the flight. There was no justification there for skipping the memory items and going to an ADR Check Procedure. I mean, that's absurd. Again, where is this resistance to a safe, practiced and memorized procedure coming from?
          In this case it's coming from Airbus. If you disagree, that's certainly your business. "Safety of flight is impacted" in this case means "are you fixin' to hit something?". If the answer is no, you don't do the memory item. The "context" of this memory item is to get you somewhere where you can "level off and troubleshoot" (it says as much). If that's absurd to you, once again, that's your business. Now, there was certainly no justification for what they DID do, but that does not make the memory item applicable.

          Comment


          • #65
            Originally posted by ATLcrew View Post
            ...Negative...Affirmative...Negative...Affirmative...
            The best scene from the movie Anchormanhttp://www.imdb.com/title/tt0357413/


            Especially, "LOUD NOISES"
            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

            Comment


            • #66
              Originally posted by ATLcrew View Post
              In this case it's coming from Airbus. If you disagree, that's certainly your business. "Safety of flight is impacted" in this case means "are you fixin' to hit something?". If the answer is no, you don't do the memory item. The "context" of this memory item is to get you somewhere where you can "level off and troubleshoot" (it says as much). If that's absurd to you, once again, that's your business. Now, there was certainly no justification for what they DID do, but that does not make the memory item applicable.
              I think you are misinterpreting this. Can you provide us with your companies' actual training definition of 'safety of the flight is impacted'?

              If it said 'safety of the flight path is impacted' then I'd understand (though I would not understand the logic, since leveling off is probably a good way to hit something). But to my untrained mind, 'safety of the flight is impacted' means a lot more than flight path.

              And the memory procedure still includes 'Above THRUST RED ALT and Above FL100'. So what are you fixin' to hit there? A mountain? If so, why would you want to level off? If anything, 'fixin' to hit something' is only a good reason NOT to use the memory procedure.

              What am I missing?

              Comment


              • #67
                Originally posted by Evan View Post
                1) A good way to hit something
                2) THRUST RED ALT and Above FL100'.
                3) What am I missing?
                The answer to "3" is that because you are so focused on acronyms ("2"), you cannot comprehend "1".

                If the plane is flying along perfectly well, don't phugoid it up by pulling the potentially WRONG memory item out of your overloaded head.

                Fly on, and CAREFULLY diagnose what's going on, talk, review checklists, consult the Book of Acronyms, recall 172 fundamentals.

                The tough thing is that it prolly would have worked (including totally cowboy improvising on familiar P,P&P + 172 fundamentals- even though that shouldn't be the "choice" per se.)
                Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                Comment


                • #68
                  Originally posted by Evan View Post
                  5 deg and climb is the memorized part, the stabilizing part, which only needs to be sustained for a brief period of time while the more appropriate values are obtained from the QRH. But you know this...
                  The same is true for the "don't touch anything" procedure. Note that you should transition from the 5 deg / CLB to the "level off" when you are at or above MSA or Circuit Altitude. What if you are already leveled off above the MSA?

                  Also, the QRH procedure includes getting the autothrust out of thrust lock[/quote]
                  Does it?


                  And actually turning off the flight directors that were intermittantly giving the pilots very bad direction.
                  Yep, you have to do so even if you don't do the memory items.
                  It is the first items under "To level off for torubleshooting", which is the first thing you in the QRH if you don;t do the memory items.

                  Seriously, there was nothing fat dumb or happy about what AF447 fell into and the situation was absolutely impacting the safe conduct of the flight.
                  How so?

                  "UAS, just keep it there, UAS QRH items please, skip memory items, AP/FD/AT off, for our weight and altitude keep this thrust and pitch (which, go figure, would have been 2.5 deg and 79% N1 initial target), flight technique: adjust pitch to keep the desired flightpath, if pitch increase increase thrust, if pitch decreases decrease thrust, when flight path is stabilized... (troubleshooting starts)"

                  ALL THAT IS IN THE QRH AND YOU HAVE TO DO IT WHETHER YOU JUDGE THE SAFE CONDUCT OF THE FLIGHT AND DO THE MEMORY ITEMS OR THAT IT IS NOT AFFECTED AND SKIP THE MEMORY ITEMS.

                  Again, if you skip the memory items the first thing in the QRH is the level-off pitch/thrust and the next thing is the flight technique to stabilize speed.
                  So the only difference is if you keep it stable where it was until you get the QRH out or if you go memory items in the meantime.

                  There was no justification there for skipping the memory items and going to an ADR Check Procedure. I mean, that's absurd. Again, where is this resistance to a safe, practiced and memorized procedure coming from?
                  And it looks to me that you are all for following the procedure until it doesn't feet your mental picture.

                  --- 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


                  • #69
                    Originally posted by Evan View Post
                    If it said 'safety of the flight path is impacted' then I'd understand (though I would not understand the logic, since leveling off is probably a good way to hit something). But to my untrained mind, 'safety of the flight is impacted' means a lot more than flight path.
                    You are misunderstanding it. The memory items are there to provide a reasonable CLIMB until above the MSA, and THEN LEVEL OFF using the specific QRH table. It is written there verbatim.

                    And the memory procedure still includes 'Above THRUST RED ALT and Above FL100'. So what are you fixin' to hit there? A mountain? If so, why would you want to level off? If anything, 'fixin' to hit something' is only a good reason NOT to use the memory procedure.

                    What am I missing?
                    A LOT!!!

                    There are plenty of things that you can hit at FL100 which is MSL, including the runway.
                    And this is to CLIMB, not to LEVEL OFF. You are not supposed to level off until AFTER REACHING THE MSA, which where you will not hit anything. Level off if the first action AFTER (and out of) the memory items.

                    Did you note that there is no "above FL320" (or anything after FL100) for the memory items but yes for the level off table?

                    --- 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


                    • #70
                      Originally posted by Evan View Post
                      I think you are misinterpreting this.
                      I think you're reaching.

                      Comment


                      • #71
                        Originally posted by Gabriel View Post
                        And it looks to me that you are all for following the procedure until it doesn't feet your mental picture.
                        OK, let's examine at my mental picture. The picture concerns the very first, immediate pilot actions while gathering situational awareness, from the moment ADR DISAGREE and unreliable speeds is acknowledged. I consider this to be the critical danger zone.

                        What are the GOAL's here?
                        1. To avoid structural damage or loss of control from overspeed.
                        2. To avoid stall from underspeed.
                        3. To avoid significant departure from flight level in RVSM airspace.
                        4. To avoid an in-flight upset that might lead to a loss of control.

                        I consider #4 to be the most immediate goal.

                        What are the options?
                        1. Maintain current (stable) flight path.
                        2. Apply the memorized (and practiced) procedure.
                        3. Improvise new pitch and power settings.

                        Option #1: Certainly this will work if there is nothing to upset the flight path AND the flight path is, in fact stable to begin with (AF447's was not).
                        Option #2: Certainly this will work in any case unless it is executed incorrectly (failure of memory, although "5 and Climb" is pretty hard to forget).
                        Option #3: Certainly this will work if the pilot has practiced airmanship skills at altitude, clear situational awareness and sound judgment despite the disorienting nature of startle and stress (AF447 showed us how unreasonable that is).

                        So which is the most uncertain? Definitely #3 (the one taken by AF447). That leaves two options.

                        Option #1 minimizes the possibilty of upset, since there is no significant deviation from the current flight path, but it is conditional. It relies on sound situational awareness in a very complex aircraft with stealth factors involved. As a first action, with no procedural guidance, there is no immediate provision to assure these factors have been addressed (AF447 did not immediately address these factors, nor did at least five of the eleven documented cases of high altitude UAS involving loss of autoflight listed in the AF447 final report).

                        Option #2 carries only a slightly higher risk of upset because it does require a deviation from the flight path but it is still very simple to execute and, unless executed incorrectly, is unconditionally effective.

                        If (and only if) Option #1 is indeed stable to begin with and is followed immediately by the UAS procedure and level-off pitch and power tables (assuming above MSA), I don't have a problem with that.

                        I prefer Option #2 because it establishes a known stable flight path and it integrates the stealth factor avoidance items, specifically setting power correctly and shutting off the FD's and is not affected by inaccurate altimeter reading.

                        Option #3 is, sooner or later, a recipe for disaster (as AF447 has shown us). This cannot be the chosen option (though it most often is).

                        A few things I can't parse with logic:

                        Thing #1) Page 17 of the Unreliable Speed Airbus slideshow we are looking at. The new 'combined' procedure goes like this:
                        1. Memory Items or Not.
                        2. Level off (for troubleshooting) procedure using QRH pitch and power tables.
                        3. Troubleshooting (UAS/ADR Disagree).
                        4. Pitch and power tables.

                        Aren't we doing something twice there, and if so, why?

                        Thing #2) In level flight, if the safety of the flight is impacted because you are "fixin' to hit something", why would maintaining the current flight path be preferred over the Memory Items?

                        Thing #3) What is actually meant by "does not affect the safe conduct of the flight" (the actual wording used by Airbus on the written UAS procedure instructing us to skip the memory items and go directly to the ADR disagree procedure).

                        Comment


                        • #72
                          Originally posted by Gabriel View Post
                          There are plenty of things that you can hit at FL100 which is MSL, including the runway.
                          Ok, so then I just need a list of runways that are above THRUST RED ALT (the word following that is 'and', not 'or').

                          Comment


                          • #73
                            Originally posted by Evan View Post
                            Ok, so then I just need a list of runways that are above THRUST RED ALT (the word following that is 'and', not 'or').
                            Ok, lt me correct my previous statement.

                            With runways at elevations above or slightly below 10000ft, there may be many terrain features and other stuff that can be hit below thrust reduction altitude which is typically not below 1500 ft above the runway elevation. You are intentionally splitting hairs (no complaint, I am an expert in that) and avoiding more important stuff (complaint here) like the fact that the memory items pitch and thrust setting end when you reach MSA or circuit altitude and then you need to go to the QRH tables to level off and apply the flight technique to stabilize speed (described after the tables).

                            --- 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


                            • #74
                              Originally posted by Evan View Post
                              OK, let's examine at my mental picture. The picture concerns the very first, immediate pilot actions while gathering situational awareness, from the moment ADR DISAGREE and unreliable speeds is acknowledged. I consider this to be the critical danger zone.

                              What are the GOAL's here?
                              1. To avoid structural damage or loss of control from overspeed.
                              2. To avoid stall from underspeed.
                              3. To avoid significant departure from flight level in RVSM airspace.
                              4. To avoid an in-flight upset that might lead to a loss of control.

                              I consider #4 to be the most immediate goal.

                              What are the options?
                              1. Maintain current (stable) flight path.
                              2. Apply the memorized (and practiced) procedure.

                              Option #1: Certainly this will work if there is nothing to upset the flight path AND the flight path is, in fact stable to begin with (AF447's was not).
                              Option #2: Certainly this will work in any case unless it is executed incorrectly (failure of memory, although "5 and Climb" is pretty hard to forget).

                              Option #1 minimizes the possibilty of upset, since there is no significant deviation from the current flight path, but it is conditional. It relies on sound situational awareness in a very complex aircraft with stealth factors involved. As a first action, with no procedural guidance, there is no immediate provision to assure these factors have been addressed (AF447 did not immediately address these factors, nor did at least five of the eleven documented cases of high altitude UAS involving loss of autoflight listed in the AF447 final report).

                              Option #2 carries only a slightly higher risk of upset because it does require a deviation from the flight path but it is still very simple to execute and, unless executed incorrectly, is unconditionally effective.

                              If (and only if) Option #1 is indeed stable to begin with and is followed immediately by the UAS procedure and level-off pitch and power tables (assuming above MSA), I don't have a problem with that.

                              I prefer Option #2 because it establishes a known stable flight path and it integrates the stealth factor avoidance items, specifically setting power correctly and shutting off the FD's and is not affected by inaccurate altimeter reading.
                              Read carefully what you've just written. Are you being fair? Because I am smelling confirmation bias.
                              If you after careful reflection you still don't agree, we can discuss.

                              A few things I can't parse with logic:

                              Thing #1) Page 17 of the Unreliable Speed Airbus slideshow we are looking at. The new 'combined' procedure goes like this:
                              1. Memory Items or Not.
                              2. Level off (for troubleshooting) procedure using QRH pitch and power tables.
                              3. Troubleshooting (UAS/ADR Disagree).
                              4. Pitch and power tables.

                              Aren't we doing something twice there, and if so, why?
                              Because you still got the wrong picture. You've taken off in IMC, are climbing out and you fly through a flock of birds that damage your pitot tubes.
                              1) Don't crash against the ground. You don't see what's around you. Are you below a safe altitude? Memory items to ensure a reasonable climb.
                              2) When you reach a comfortable location and altitude to troubleshoot, level off using the QRH tables.
                              3) Stabilize the speed using the QRH flight technique.
                              4) Troubleshoot.
                              5) Still no valid speed insdication? Ok, it seems that you will have to complete the flight with no speeds. What's next? You can't return to land in IMC, you need VMC at least for the landing. There is a suitable airpot over there across the mountain range but you also need to save fuel. So you will need to a) Climb to the desired and safe cruise altitude (table), b) level off at the desired cruise altitude and c) descend when approaching the diversion airport.

                              Thing #2) In level flight, if the safety of the flight is impacted because you are "fixin' to hit something", why would maintaining the current flight path be preferred over the Memory Items?
                              No, if you are fixin' to hit something, use the memory items to climb. That is what they are designed for. Now, if you are NOT fixin' to hit something, well, read what you've put above and see if the comparative evaluation of options #1 and #2 is fair.


                              Thing #3) What is actually meant by "does not affect the safe conduct of the flight" (the actual wording used by Airbus on the written UAS procedure instructing us to skip the memory items and go directly to the ADR disagree procedure).
                              I think that ATL answered that already . A million times.

                              --- 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


                              • #75
                                this brings new meaning to the word "stubborn"

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