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  • Originally posted by Deadstick View Post
    ...So I recovered from the spin and asked him what he'd like me to do with the dead engine. We were at 5000 feet over the Ramona CA airport and he said "land it." I said "deadstick?" (Hence my screen name) and he said no, go ahead and restart but don't use any power. So I put it on the numbers with the engine idling...
    I'm thinking there's about two things you failed to do to make this story real good!

    1) Gone flying around in sight-seeing mode to burn off some of your altitude.

    2) Maybe located and played with some thermals- probably hard to acheive a climb, but, it would have been quite the deal.

    Of course, to be serious the proper procedure would be circle down to landing, so sight seeing and playing might have kept you from passing.
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

    Comment


    • Originally posted by Gabriel View Post
      ...I did just one flight in a glider (with an instructor) and I was horrible in the tow part (definitively I would have not wanted to be the tow pilot of that flight)...
      Bump...updraft...wow cool...whoops, I'm kind of above the tow plane, this is bad, I'll pull his tail up and he'll dive...I better nose over...

      oh crap, the rope is going slack...yeah, that's right, speed increases when you nose over...I better pull back up...

      oh crap, the rope is losing slack...real quickly...#$^%#$!

      This sucks, I mean I'm basically staying behind the tow plane! @#%@#!

      Then later. Bump updraft climb...wow cool...now circle back and hit it again. Yeah sure, no problem...ok 180 degrees....were's the damn thing...it was right here I SWEAR...Oh, thanks instructor, wow, that's quite the sense and skill to visualize and find these invisible rising bubbles of air.
      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

      Comment


      • Originally posted by 3WE View Post
        Bump...updraft...wow cool...whoops, I'm kind of above the tow plane, this is bad, I'll pull his tail up and he'll dive...I better nose over...

        oh crap, the rope is going slack...yeah, that's right, speed increases when you nose over...I better pull back up...

        oh crap, the rope is losing slack...real quickly...#$^%#$!

        This sucks, I mean I'm basically staying behind the tow plane! @#%@#!


        So you have been up there too, uh?

        --- 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


        • Yes, once. I didn't like the livery.
          Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

          Comment


          • William Langewiesche explores how a series of small errors can turn a state-of-the-art cockpit into a death trap.




            final excerpt

            Captain Dubois entered the cockpit 1 minute and 38 seconds after the pitot tubes malfunctioned. It is not known whether he knelt or stood behind Bonin and Robert, or sat in the jump seat. Likewise, the conditions in the passenger cabin are not known. Though the unusual motions must have been noticed by some, and the passengers seated in front may have heard the cockpit alarms, there is no evidence that panic broke out, and no screams were recorded.

            In the cockpit, the situation was off the scale of test flights. After Dubois arrived, the stall warning temporarily stopped, essentially because the angle of attack was so extreme that the system rejected the data as invalid. This led to a perverse reversal that lasted nearly to the impact: each time Bonin happened to lower the nose, rendering the angle of attack marginally less severe, the stall warning sounded again—a negative reinforcement that may have locked him into his pattern of pitching up, assuming he was hearing the stall warning at all.

            Dubois pointed to an indication on a flight display. He said, “So, here, take that, take that.”

            Robert repeated the order more urgently. “Take that, take that! But try to take that!”

            The stall warning erupted again. Bonin said, “I have a problem—it’s that I don’t have a vertical-speed indication anymore!” Dubois merely grunted in response. Bonin said, “I have no more displays!” This was not correct. He had displays but didn’t believe them. The descent rate was now 15,000 feet per minute.

            Robert was suffering from the same disbelief. He said, “We don’t have a single valid display!”

            Bonin said, “I have the impression we’re going crazily fast! No? What do you think?” He reached for the speed-brake lever and pulled it.

            Robert said, “No. No! Above all don’t extend the brakes!”

            “No? O.K.!” The speed brakes retracted.

            At times both of them were on their side-sticks, countermanding each other on the controls. Bonin said, “So, we’re still going down!”

            Robert said, “Let’s pull!”

            For 23 seconds Captain Dubois had said nothing. Robert finally roused him. He said, “What do you think? What do you think? What do you see?”

            Dubois said, “I don’t know. It’s descending.”

            It is said in his defense that he faced an indecipherable scene, having arrived after the loss of control, but his observer status was actually an advantage. He knew nothing of the original airspeed-indication failure. Now he had a functional panel, showing low airspeeds, a low ground speed, a nose-high attitude, and a big descent under way. Add to that the repeated stall warnings, the telltale buffeting, and the difficulty in controlling roll. It might have been helpful to have an angle-of-attack display—one capable of indicating such extremes—but what else could this be but a stall?

            Bonin had managed to come out of the sustained right bank. He said, “There you are! There—it’s good. We’ve come back to wings level—no, it won’t . . . ” The airplane was rocking between left- and right-bank angles up to 17 degrees.

            Dubois said, “Level the wings. The horizon, the standby horizon.”

            Then things got even more confused. Robert said, “Your speed! You’re climbing!” He probably meant that Bonin was raising the nose, because the airplane was emphatically not climbing. He said, “Descend! Descend, descend, descend!,” again apparently referring to pitch.

            Bonin said, “I am descending!”

            Dubois picked up the language. He said, “No, you’re climbing.”

            Bonin may have realized that the reference was to pitch. He said, “I’m climbing? O.K., so we’re going down.”

            Communication in the cockpit was withering. Robert said, “O.K., we’re at TOGA.”

            Bonin asked, “What are we now? In altitude, what do we have?” Apparently he was too busy to see for himself.

            Dubois said, “Fuck, it’s not possible.”

            “In altitude what do we have?”

            Robert said, “What do you mean ‘in altitude’?”

            “Yeah, yeah, I’m descending, no?”

            “You’re descending, yes.”

            Bonin never got his answer, but the airplane was dropping through 20,000 feet. It rolled into a steep, 41-degree bank to the right. Dubois said, “Hey, you, you’re in . . . Put, put the wings level!”

            Robert repeated, “Put the wings level!”

            “That’s what I’m trying to do!”

            Dubois was not happy. He said, “Put the wings level!”

            “I’m at full left stick!”

            Robert moved his own side-stick. A synthetic voice said, DUAL INPUT.

            Dubois said, “The rudder.” This did the trick, and the airplane righted. Dubois said, “Wings level. Go gently, gently!”

            In confusion, Robert said, “We’ve lost everything on the left wing! I have nothing left there!”

            Dubois answered, “What do you have?,” then “No, wait!”

            Bonin said, “We’re, we’re there, we’re getting to level 100!”

            Robert said, “Wait! Me, I have the, I have the controls, me!” He did not push his priority button, and Bonin did not relinquish his stick. The synthetic voice said, DUAL INPUT. The airplane’s angle of attack remained at 41 degrees.

            Bonin said, “What is it? How is it that we’re continuing to descend so deeply?”

            Robert directed Captain Dubois to the overhead switching panel. He said, “Try to see what you can do with your controls up there! The primaries, etc.”

            Dubois said, “It won’t do anything.”

            Bonin said, “We’re getting to level 100!” Four seconds later he said, “Nine thousand feet!” He was struggling to keep the wings level.

            Dubois said, “Easy on the rudder.”

            Robert said, “Climb, climb, climb, climb!” He meant, Pitch up!

            Bonin said, “But I’ve been at full-back stick for a while!” DUAL INPUT.

            Dubois said, “No, no, no! Do not climb!” He meant, Do not pitch up!

            Robert said, “So go down!” DUAL INPUT.

            Bonin said, “Go ahead—you have the controls. We are still in TOGA, eh.” Someone said, “Gentlemen . . . ” Otherwise, for the next 13 seconds none of them spoke. Count it on a clock. Robert was doing the flying. The cockpit was lousy with automated warnings.

            Dubois said, “Watch out—you’re pitching up there.”

            Robert said, “I’m pitching up?”

            “You’re pitching up.”

            Bonin said, “Well, we need to! We are at 4,000 feet!” But pitching up is what had gotten them into trouble to start with. The ground-proximity warning system sounded. A synthetic voice said, SINK RATE. PULL UP.

            Dubois said, “Go on, pull.” With that, it seems, he had resigned himself to death.

            Bonin was younger. He had a wife in the back and two little children at home. He assumed control, saying, “Let’s go! Pull up, pull up, pull up!”

            Robert said, “Fuck, we’re going to crash! It’s not true! But what’s happening?”

            In sequence the alarms were sounding PULL UP, C-chord, STALL, C-chord, PULL UP, PRIORITY RIGHT. At the same time either Robert or Bonin said, “Fuck, we’re dead.”

            Dubois calmly said, “Ten degrees pitch.”
            AirDisaster.com Forum Member 2004-2008

            Originally posted by orangehuggy
            the most dangerous part of a flight is not the take off or landing anymore, its when a flight crew member goes to the toilet

            Comment


            • Originally posted by James Bond View Post
              In the cockpit, the situation was off the scale of test flights. After Dubois arrived, the stall warning temporarily stopped, essentially because the angle of attack was so extreme that the system rejected the data as invalid. This led to a perverse reversal that lasted nearly to the impact: each time Bonin happened to lower the nose, rendering the angle of attack marginally less severe, the stall warning sounded again—a negative reinforcement that may have locked him into his pattern of pitching up, assuming he was hearing the stall warning at all.
              This is VERY simple to understand. When airspeed indications drop below 60kts, the AoA sensors are considered unreliable and so is the data from those sensors that drives the stall warning. Insufficient airflow to drive AoA vanes: no stall warnings. For very good reasons.

              So, in a UAS situation, EVERY AIRBUS PILOT SHOULD KNOW THIS: You've lost airspeeds, the stickshaker might not function correctly, therefore don't upset the flight path and follow the procedures to remain in the envelope. But If you botch that part and leave the stable flight path, respect stall warnings but DO NOT RELY ON THEM. Detect stall by monitoring the instruments that are still reliable without speeds, such as the horizons, the engine power levels and the VSI. KNOW how to identify stall without airspeed data. KNOW how to recover from stall without airspeed data.

              This was off the scale of a test flight because I expect test pilots to understand all of the above. I also expect line pilots to have this understanding. What happened to AF447 was not a confusing failure of systems, it was a lack of systems knowledge and a lack of basic airmanship due to a lack of training at Air France (and god knows how many other airlines).

              If you fly a specific type, do your homework. Read the FCOM, read the supplementals, read the forums. Learn how it all works. It's not just a job, it's a huge responsibility and it's not the analogue 1960's anymore. You're not just a pilot, you're a systems administrator.

              That transcript is still too outrageous to read.

              Comment


              • Evan, you are making it more complicated than it is.
                Use the engines instruments to figure the AoA? That's new.
                Even the attitude indicator combined with the VSI can be complex, unless the VSI is near zero (and hence the AoA is close to the pitch) or the situation is so ridiculous that you don't care for any "accurate" AoA: Nose 10° up + Plane 10000fpm down = too much AoA. But then, I bet the AoA vanes at below 60 kts would be a good indication, even if the indicated AoA is off by some degrees. And ten, no, an Airbus can nit be in the air at 60kts or less (except for a very brief period of time) so "Airbus in the air" is a very good approximation to "speed above 60 kts" (no matter what the ASI shows). What I mean is that I see no reason to regard the AoA data useless at any indicated speed with the plane in the air. And the negative feedback issue is very real. Maybe (big maybe) Dobois would have noted the stall if the warning was persistent. Maybe Robert would have kept pushing down if the stall warning would not have started again when he did so.

                Maybe the plane was still recoverable when Dubois entered the cockpit and (about the same time) they started to have the negative feedback of the stall warning.

                But it is very amazing that they reached to that point. Before that, and starting with the AP and AT going off at an altitude close to their ceiling, they:
                - Pulled up 1.2Gs during several seconds reaching 7000 fpm, 15 deg nose up and climbing 2500 ft or so.
                - At the top of the climb, when the stall warning started, they pulled up again and climbed another 1000ft or so.
                - When the plane gave up and started to fall at 10000fpm with the nose pointing 10° up, they kept pulling up.

                I understand that Airbus never figured that the plane needed to keep giving valid readings of anything after in this situation that the plane should have never been.

                Follow procedures? Sure. But again, this accident was not JUST for not following the procedures. I mean, there are different ways not to follow the procedures other than put climb above the ceiling with a maneuver that is more aggressive than a take-off, actively stall the plane, and then ensure that it remains well stalled. To say "they didn't follow the procedure" is the understatement of the year. If they had done exactly NOTHING WHATSOEVER, they would have been still not following the procedure but would have survived with no one (except the pilots) noting that there was something odd. There were only 2 ways to crash this plane: Pull up to hard and stall or push down too hard and break up. Anything in between was survivable including, of course, following the procedure that undoubtedly would have been the best and only acceptable course of action.

                That's why I am puzzled by the cherry of the cake: your last sentence.
                You're not just a pilot, you're a systems administrator.
                This accident had a good part of not being a good system administrator, I agree: not following the prescribed procedures.

                But overall, this was a pilot accident. Airman. Stick and rudder. An accident in which putting too much emphasis on system administration and not in the art of flying (and I mean just "of flying", not "of flying Airbus") was undoubtedly a causative factor.

                --- 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
                  It's not just a job, it's a huge responsibility and it's not the analogue 1960's anymore.
                  Is there any accident from that time period similar to this one?

                  Comment


                  • Originally posted by Leftseat86 View Post
                    Is there any accident from that time period similar to this one?
                    Yes. There were several cases where UAS led to loss of control.
                    Enough that the FAA modified a rule to request that alarm be on whenever the Pitot tubes are not heated.

                    --- 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
                      Evan, you are making it more complicated than it is.
                      Gabriel, you are missing my point. I agree with most of what you say but my point is that pilots MUST know how these systems work, what their limitations are and when they might be misleading. The CVR should have gone something like this:

                      Dubois: Put the nose down, you are stalled!

                      Bonin: But when I put the nose down the stickshaker comes on...

                      Dubious: You've got false airspeeds, you can't fly by the stickshaker.

                      Bonin: Oh, right, I remember this from stall recovery and UAS training.

                      The idea that the plane can 'trick' the pilots assumes that the pilots are ignorant of how the plane works and what its limitation are. It's no excuse.

                      Use the engines instruments to figure the AoA? That's new.
                      Not to figure AoA, to avoid stall. If the pitch is around x and the N1's are around y you aren't going to stall (and this you should know from memory).

                      If they had done exactly NOTHING WHATSOEVER, they would have been still not following the procedure but would have survived with no one (except the pilots) noting that there was something odd. There were only 2 ways to crash this plane: Pull up to hard and stall or push down too hard and break up. Anything in between was survivable including, of course, following the procedure that undoubtedly would have been the best and only acceptable course of action.
                      Probably true, but not absolutely. Most UAS events last only a few minutes so doing nothing might have resulted in no incident. But once again, consider this:

                      Moments before the incident they were at FL350 and .82M and required 99-100% N1 to remain there. Because they were decelerating for turbulence penetration, at the point of A/T disconnect they were at about 80% N1 but the commanded N1 was 75%. When the A/T disconnected, this was the locked in power setting. The thrust lever is in the CLB detent, indicating full climb power (near 100% N1). Now assume a crew is trying to maintain level flight at FL350. The FBW will need to continuously bring on pitch as the aircraft slows down below .80M... .70M... At FL350 and their current weight, where is stall AoA in this equation?

                      Yes, the first warning would be stickshaker, but this crew didn't think much of that. Furthermore, the startle factor and a general ineptitude at hand-flying skills resulted in a senseless sustained pitch command. Given that we ARE talking about this crew, IF the UAS was unusually prolonged and if they had done nothing but maintain level flight and then made these errors on stickshaker activation, the same end may have resulted.

                      Essentially, with THIS CREW hand-flying an A330 in alternate law, once you get stickshaker it's all over... whether that results from pulling up or from doing nothing at all.

                      The ONLY truly safe and responsible action is to follow procedures BECAUSE of the stealth factors involved (see: the history of aviation disasters). Oh, look, I'm blue in the face.

                      That's why I am puzzled by the cherry of the cake: your last sentence.
                      This accident had a good part of not being a good system administrator, I agree: not following the prescribed procedures.
                      But overall, this was a pilot accident. Airman. Stick and rudder. An accident in which putting too much emphasis on system administration and not in the art of flying (and I mean just "of flying", not "of flying Airbus") was undoubtedly a causative factor.
                      Ok, which is it? If it's a stick and rudder accident, then stop blaming the automation. It it's a stick and rudder accident compounded by a systems issue that call it a stick and rudder/systems administration error, which is what this was.

                      Comment


                      • How about we call it a "stick-and-rudder-complicated-by-misunderstanding-what-the-systems-are-doing" accident!

                        It doesn't exactly roll off the tongue but here's the thing: IMHO you can't fairly call this strictly a "stick and rudder" accident because the stick's not connected directly to the rudder! Or any other flight control surfaces of course. In between the stick and said surfaces there's a box with a large quantity of transistors and such that makes the control surfaces do different things based on stick position and 50 other things. And without knowing exactly what control inputs to that box produce the outputs you want (in real time, since the box is also processing other inputs that are constantly changing), you don't have a clear stick-rudder relationship.

                        Consider as an example all the accidents in the past that have happened due to misrigged flight controls. Every now and then a plane will come out of the shop with ailerons that deflect for a right turn when you turn the yoke left, or elevators that deflect down when you pull back on the stick. I think there's an analogy there between that and a more complex automated system that isn't producing the expected outputs for a given input. In the case of the misrigged flight controls the "automation failure" is very simple to understand... something is just reversed... but since it's not expected the outcome is almost always bad.

                        All of which doesn't necessarily excuse the pilots' failure to fully understand the relationship between control inputs and flight surfaces at all times. But I think it must be acknowledged that their task can be more difficult and confusing than that of the guy in a 172 who (except in the rare case I discuss above) never has to give significant thought to what the flight controls will do when he moves the "stick".
                        Be alert! America needs more lerts.

                        Eric Law

                        Comment


                        • Originally posted by elaw View Post
                          How about we call it a "stick-and-rudder-complicated-by-misunderstanding-what-the-systems-are-doing" accident!
                          I would favor "stick-and-rudder-complicated-by-lack-of-understanding-of-how-the-systems-work" accident.

                          FBW is a command request means of flying. You tell the plane where you want it to go and it goes there. It is a different mindset and can be more complicated than a 172, yes, when things go wrong. That's why pilots are not transitioned from a 172 to an A330 over the weekend. Pilots have to be very knowledgeable of the new technologies involved. They need to know what the job of piloting FBW involves and how it differs from the old 733. You need to be a pilot. You need to be a systems administrator. Really, being a hands-on pilot alone won't cut it anymore. Not when things get pear-shaped.

                          Comment


                          • Originally posted by elaw View Post
                            How about we call it a "stick-and-rudder-complicated-by-misunderstanding-what-the-systems-are-doing" accident!
                            I'm going one further. It's old fashioned spatial disorientation.

                            ...enhanced by an automatic system that gives vanilla, non-performance-related feedback, that is not giving you normal data and screaming that all sorts of things are wrong.

                            Not really any different than a private pilot hitting clouds with working instruments...Suddenly the world is confusing and overwhelming and what you think is up isn't up.

                            You don't know that you're not level vs. you don't know that your stalled and mushing through the air in a steep wallowing descent.

                            It's now clear that it wasn't all on the one pilot...Three intelligent, experienced guys could not determine that they were in a stall...the topic really didn't come up to any great extent in their discussions.

                            ...I blame Airbus.
                            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                            Comment


                            • Evan,

                              When I say DO NOTHING I do mean NOTHING, Keep your hand and foot off the controls. Remove the pilots from the cockpit if that's what it takes. Trying to keep FL350 doesn't qualify as "nothing" in the terms that I meant.

                              Now, in most planes not Airbus that doing nothing means that the plane would keep its trim AoA and its trim speed, gently climbing if the thrust is greater than what's needed to keep level flight or gently descending if, like in this case, it's less. That's the good point, the bad point is that in these planes probably pilot action would be required to avoid the plane from slowly starting to bank and smoothly entering a spiral dive.

                              The Airbus Alternate Law will keep the wings level with the hands off. And in pitch it will be sick on G at fast speed and stick on pitch rate at slow (but not that slow) speed.

                              So what would have happened is, if the thrust was not enough to sustain flight at that altitude and speed, the plane would start to lose speed and the FBW will slowly pitch up to keep 1 G, what would result in keeping the altitude. Now, as the plane slows down (before it gets very slow into the second regime, back side of the thrust curve, or zone of reversed commands) the plane needs less thrust to fly slower. I don't know if the setting was enough to keep the altitude at any speed. Let's say that it wasn't. So, there will be one point, somewhere below 250kts IIRC, where the law will change from stick on G to stick on pitch rate. This point will find you with the plane flying somehow nose-high, but not at a very high AoA or pitch (which up to this point were the same because the plane was flying an horizontal trajectory), and will stop increase the pitch to hold the altitude and instead will keep the pitch frozen, so the plane will start to go down at a slowly increased VSI as it slow slows down. Now, other than the thrust available, you have a second source of power to keep the speed: trading altitude for speed.

                              I can't prove it, but I feel very confident that the plane would have stabilized at a mild pitch and mild VSI (say, for example, 7 degrees nose-up and -2000 fpm) and then it would have kept going down until the altitude where that 75% N1 was enough to keep the altitude, and then kept flying for hours and hours with the pilots back in the cabin, until the plane runs out of fuel.

                              And, to clarify, I meant that this was fundamentally a (bad) stick and rudder accident. I mentioned system administration as a factor in the sense of "systemadministrationitis", that the pilots are very experienced and very well trained in managing the automation but lack experience and training in manual flight.

                              I was watching some official Airbus videos on youtube, called Airbus golden rules. At a point the instructor says in a severe voice "and these are the primary controls that you use to fly the plane" and showed... the autopilot MCP!!!!!! I was shocked. Even if it's true, don't ever say that to a pilot. Especially not if at the end of the video you say, like he did, "And remember, if the plane doesn't do what you want, you are the pilot, you are responsible to enforce the required performance. Take over" Sure, with the "primary controls used to fly the plane" or with the little, minor, lesser, secondary ones called STICK AND RUDDER for God sake!

                              --- 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 3WE View Post
                                I'm going one further. It's old fashioned spatial disorientation.
                                ...
                                Not really any different than a private pilot hitting clouds with working instruments...Suddenly the world is confusing and overwhelming and what you think is up isn't up.
                                I actually disagree. It may be disorientation, but not spatial in the classic "non-instrument-rated PPL flies into clouds and freaks and crashes because the horizon disappeared" sense.

                                The guys flying AF447 were highly trained at flying with no reference to the horizon... and most likely for some time before this accident happened they could not see the horizon. Of course at that time the AP was probably flying the plane but we'll ignore that for the sake of argument.

                                I do however think they suffered disorientation of a different type: they were flying based on instrument indications (once the autopilot decided not to), but the instrument indications were confusing and conflicting, and they didn't know which ones to believe. Layer on top of that the mistaken belief that the aircraft's systems would prevent exactly what some of the instruments say is happening, and you have the potential to create a very inaccurate mental image of what is taking place.
                                Be alert! America needs more lerts.

                                Eric Law

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