Announcement

Collapse
No announcement yet.

Air France Off the Hook on AF447

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #76
    Originally posted by Evan View Post
    It wasn't too late. The airplane was still responding to control inputs. All the instruments were functioning at the point. A quick look at the PFD told the story: high vertical speed and loss of altitude and no corresponding dive attitude or airspeed. That's a fully developed stall. Remedy: pitch down, trim down, retard thrust, speedbrakes, get the wings back in lift-generating mode. But he didn't make any such verbal announcement of the situation or direct, any forceful command to facilitate a recovery. The thing missing was situational awareness. But, when he arrived in the cockpit, they still had the time.
    I totally agree with you.

    when he arrived in the cockpit, they still had the time.
    I only exactly know 1 timeframe in aviation history. And I'll never in my life forget that. 238 seconds. For Flight Captain Chesley Sullenberger III to rescue all 155 souls on board, including himself.

    So let's assume you are not PF, you are not even in the cockpit, like Dubois. 238 seconds then are not enough for you.

    They had the time. Yes, in my eyes the PF always has 238 seconds to rescue his aircraft. Imho that was the case before AF #447 impacted on the Atlantic Ocean, with a speed of.. cruise speed at 350 plus x.. as far as I remember, the French BEA stated that the AF A332 impacted almost flat on the Ocean, i.e. not with a nose dive, but with the full length of an A332,
    a belly landing with let's say 500 knots ground speed. Nobody and nothing survives something like that if not somebody releases the yoke so that the jet almost automatically flies out of the stall, a proper altitude assumed. The right seat F/O must have died on impact, still ripping the yoke.

    At least one question remains. I don't have an idea how to distribute 'You have control' in an Airbus 330. I assume that in a Boeing 747 -100, -400 or -800 or all other versions, both yokes move if not the matter who pulls one of them. So, in a 747, the left seat F/O always sees the move when somebody else like a temporarily shocked right seat F/O pulls his yoke far beyond a good airspeed.

    Pulling the yoke is one of the best airbrakes which I know. And that is true for each and every aircraft which I know. Grumman Goose, Cessna 152, Cessna 172, Cessna Citation, Beech Baron 58, Beech King Air 350, Airbus A320, Airbus A321, Airbus A330, B757, B763ER 764ER, 744ER, 748 passage, 748 freighter, et cetera et cetera et cetera.

    So how could he pull until he died. He was unaware of the situation, he did not see the Ocean coming although he pulled like an insane person. Missing situational awareness, in darkness above the Atlantic Ocean. He probably was not able to see the Ocean coming in the darkness,
    but hell damn that was not his first flight as a PF in the right seat of an Airbus 330-200 in darkness (?!).

    In Germany, afaik you need an IFR license to start the engine of whatever aircraft without sunlight. That includes precise knowledge of all instruments in an Airbus 330 or Beech Baron 58 to avoid a belly landing on the Atlantic Ocean: PFD, v/s indicator and alt indicator. What would you try if you have an old school altitude indicator clock in your aircraft which is spinning like a toy spinner (Spielzeugkreisel) during a descent. You try to end with a normal landing, with a flare. But only with more than stall speed.

    Stall recovery or emergency descent is possible, afaik, not only in the movie 'U.S. Marshals' (1998_). 'I have her at 10,000 !'

    Didn't AF #447 end quite flat on the Ocean or even with 2 or 3 degrees nose up?! Thus he never was able to regain more than stall speed.

    One of the saddest stories since I am here in this forum, AF #447. Because highly avoidable.
    LH and the Hamburg - Düsseldorf - Shannon - NYC route, open since June 1st, 1955. A/C type: Lockheed Super Constellation.
    LH is member in the 747 club since April 1970. Jubilees do count, believe me.
    Aviation enthusiast since more than 30 years.

    Comment


    • #77
      AF447 was falling with a pitch attitude of about 10 degrees nose up and a sink rate of some 10000 fpm. It crashed more or less with those parameters, with the wings almost level.

      --- 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


      • #78
        Originally posted by Gabriel View Post
        Trim down? Wasn't the autotrim still active? Holding the stick forward should have provided the commanded nose-down pitch rate or at least the plane would have attempted to do that and because possibly it would not have been able to (against the nose-up pitching moment of the engines) it would have added nose-down trim by itself with no additional pilot intervention other than holding the stick forward (in the same way as it trimmed almost fully nose-up in response to making mostly nose-up inputs).
        Despite variations in pitch command, including nose down commands, the trim remained at about 13deg nose up from around the time the captain entered the cockpit until the crash. I'm still unclear as to why (control law was 'alternate 2B'), but my addition of "trim down" is provisional: if pitch is not responding fast enough to elevator commands. This is what i would call "universal airmanship".

        Speedbrakes? SPEEDBRAKES?!?!? Fly below Vne???? They were well below Vne the whole time. Do you mean after the dive resulting from the stall recovery?
        Again, provisional. You need airspeed as fast as possible without overspeed, then you need to recover lift and level flight. So provisions are there to avoid overspeed.

        (*) When the captain arrived to the cockpit, almost simultaneous the stall warning (that had been sounding uninterruptedly for almost a minute since the stall at the top of the climb) stopped sounding because the indicated airspeed went below a very low speed threshold, much lower than the already very low real airspeed, now not because of the icing that had already cleared but because of the extremely high AoA. This very low speed threshold, just double digits in knots, is considered too slow for the AoA vanes to provide relaible indications, so the stall warning is inhibited below that speed. When the PNF took the controls for some seconds and applied significant nose-down inputs, the AoA clearly started to reduce and with that the indicated airspeed started to increase (due to the pitots becoming more aligned with the relative wind) and hence the AoA indication was considered reliable again and, being it still way to high (even if not as high as seconds earlier), the stall AoA activated again. This possibly was very confusing: The stall warning went silent. I push down and it starts again. Sure enough, he pulled up again and the stall warning stopped again, kinda reinforcing that pushing down activated the stall warning and pulling up made it sound. I wonder if they realized of this and made some wrong conclusions.
        I'm glad to see you are back to acknowledging the human factors. The system considers AoA sensor data invalid under 60kts (for obvious good reason), and yes, that would reinforce an erroneous situational interpretation. The same is true when the flight directors contradict the stall warnings before the actual stall (a point you seem to have dismissed). To apply your argument against the junior first officer to the captain, the clear instrument indications (valid in this case) as well as buffet should have been enough to reveal the true situation despite the confusing elements.

        BTW: my argument is still that, once the situational awareness is lost in the first place, you're as good as dead, as are all of your passengers, and therefore we need procedures, procedural training and procedural discipline to assure this never occurs. Beyond that, we really can't find blame for vulnerability to human factors.

        Comment


        • #79
          Originally posted by Evan View Post
          ***we need procedures, procedural training and procedural discipline to assure this never occurs.***
          One procedure I remember from 172 school is just about ALMOST ALWAYS maintain healthy attitudes and airspeeds and do not make relentless pull ups.

          It is such a shame that this is a type specific procedure that would not work on an A-300.

          "procedural discipline" Yeah, I'm still at a loss to explain that (including for the 172 version of the procedure).
          Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

          Comment


          • #80
            Originally posted by 3WE View Post
            One procedure I remember from 172 school is just about ALMOST ALWAYS maintain healthy attitudes and airspeeds and do not make relentless pull ups.

            It is such a shame that this is a type specific procedure that would not work on an A-300.

            "procedural discipline" Yeah, I'm still at a loss to explain that (including for the 172 version of the procedure).


            Way back in the early 90's I was flying DC-8's. Flying in and out of Saudia Arabia during Desert Storm/Shield. On a ferry trip back west across the Atlantic we were at Fl 410, max certified altitude. Half way across we ran into a temperature change. It started warming up and we had to increase power to maintain cruise mach. We finally had to go down to maintain speed. Not what you'd expect.

            Comment


            • #81
              Originally posted by kent olsen View Post
              Way back in the early 90's I was flying DC-8's. Flying in and out of Saudia Arabia during Desert Storm/Shield. On a ferry trip back west across the Atlantic we were at Fl 410, max certified altitude. Half way across we ran into a temperature change. It started warming up and we had to increase power to maintain cruise mach. We finally had to go down to maintain speed. Not what you'd expect.
              So you were monitoring speed and altitude, and when speed decayed, you added power and then descended since you had a little bit of extra altitude to work with.

              I guess we didn’t learn exactly that in 172 school (that a temperature change might get you closer to coffin corner.)

              That being said, it would appear that you continued to fly the plane using some basic airmanship fundamentals and that for some reason, you didn’t pull up relentlessly.

              Did you do this based on a particular procedure or checklist, or just “wing it” using common (cowboy improvisational) sense?
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

              Comment


              • #82
                Originally posted by 3WE View Post
                I guess we didn’t learn exactly that in 172 school (that a temperature change might get you closer to coffin corner.)
                He was flying the plane at its max certified altitude. How many times did you do that in a 172?

                (In the Tomahawk I never came close, the service ceiling is 12000 ft and the max I climbed was 8500).

                --- 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


                • #83
                  Originally posted by kent olsen View Post
                  Way back in the early 90's I was flying DC-8's. Flying in and out of Saudia Arabia during Desert Storm/Shield. On a ferry trip back west across the Atlantic we were at Fl 410, max certified altitude. Half way across we ran into a temperature change. It started warming up and we had to increase power to maintain cruise mach. We finally had to go down to maintain speed. Not what you'd expect.
                  This is a very good point. One of the things we overlooked is the rapid temperature change associated with this ITCZ updraft phenomena and how that might affect 'healthy airspeeds' with no valid airspeed indication.
                  The consensus here seems to be that maintaining current pitch and power (doing nothing to either) is sufficient, but that assumes everything is constant. If the air temperature rises suddenly and significantly, is the current pitch and power sufficient to maintain altitude at a safe airspeed?
                  The premise I'm basing the risk on is that the pilots in manual flight will focus on maintaining current altitude (level flight) rather than pitch and power (either current settings or QRH derived values).

                  Comment


                  • #84
                    Originally posted by Evan View Post
                    This is a very good point. One of the things we overlooked is the rapid temperature change associated with this ITCZ updraft phenomena and how that might affect 'healthy airspeeds' with no valid airspeed indication.
                    The consensus here seems to be that maintaining current pitch and power (doing nothing to either) is sufficient, but that assumes everything is constant. If the air temperature rises suddenly and significantly, is the current pitch and power sufficient to maintain altitude at a safe airspeed?
                    The premise I'm basing the risk on is that the pilots in manual flight will focus on maintaining current altitude (level flight) rather than pitch and power (either current settings or QRH derived values).
                    (I realize that AF447 was not at REC MAX at the event onset. But what if this occurs to a flight already at REC MAX?)

                    Comment


                    • #85
                      Originally posted by Gabriel View Post
                      He was flying the plane at its max certified altitude. How many times did you do that in a 172?
                      1. Never. (And I did acknowledge that, although never to YOUR satisfaction)
                      2. I enjoyed his story.
                      3. I am NOT sure what his point was.
                      4. I don’t think I was ARGUING with him, BUT, it’s possible I am.
                      5. I am very serious about ‘the basic fundamentals’:

                      It would appear he monitored airspeed, While I never went to the 172 ceiling, I’m pretty sure I would have descended if I were on board the DC-8 and Kent et al ate bad fish, and I’m pretty sure I would not have done a hard pull up (which Kent also did not).

                      Good enough for you, or do you need to spew some more aero engineer stuff?
                      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                      Comment


                      • #86
                        Originally posted by Evan View Post
                        ****how that might affect 'healthy airspeeds' with no valid airspeed indication.
                        The consensus here seems to be that maintaining current pitch and power (doing nothing to either) is sufficient***
                        1. Wrong
                        2. Bull crap

                        It’s ROBUST power and attitude, NOT MAINTAIN ALTITUDE AND AIRSPEED AT ALL COSTS. It's NOT maintain marginal power and pitch.

                        You are making a straw man that at a CRITICAL Uber-high altitude, you must maintain attitude and altitude.

                        NO ONE said that.

                        (Maybe Kent Olson made the same argument, or maybe he didn’t.)

                        Instead, what was said was YOU SURE AS HELL DON’T DO AN AGGRESSIVE PULL UP!.

                        If you are coffin corner high, you let the plane DESCEND if it wants...select a ROBUST configuration...DO NOT do an aggressive pull up...

                        Have we already forgotten “RECMAX” which you see as an OK for a hellacious pull up?

                        In my world “RECMAX” equals some buffer to not phugoid with the nice steady flight to any significant degree.
                        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                        Comment


                        • #87
                          Originally posted by 3WE View Post
                          1. Never. (And I did acknowledge that, although never to YOUR satisfaction)
                          2. I enjoyed his story.
                          3. I am NOT sure what his point was.
                          4. I don’t think I was ARGUING with him, BUT, it’s possible I am.
                          5. I am very serious about ‘the basic fundamentals’:

                          It would appear he monitored airspeed, While I never went to the 172 ceiling, I’m pretty sure I would have descended if I were on board and Kent et al ate bad fish, and I’m pretty sure I would not have done a hard pull up (which Kent also did not).

                          Good enough for you, or do you need to spew some more aero engineer stuff?
                          Don't take me wrong. That I quote and commented on a fraction of a sentence of your post doesn't say anything of what I think of your post at great.

                          I was just saying why you and me never had to worry about the air temperature becoming warmer at the altitude we were flying. Because, as you said, I am pretty sure we would not have kept pulling up trying to hold and unholdable altitude to the point of stall or even close.

                          --- 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


                          • #88
                            Originally posted by Gabriel View Post
                            you and me never had to worry about the air temperature becoming warmer at the altitude we were flying.
                            In our years of beating this subject to death, I remember real pilot saying something to the effect that he wouldn't be adverse to a gradual descent using familiar and robust power settings and attitudes if the plane's computer went berserk at a very high altitude.
                            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                            Comment


                            • #89
                              Originally posted by 3WE View Post
                              In our years of beating this subject to death, I remember real pilot saying something to the effect that he wouldn't be adverse to a gradual descent using familiar and robust power settings and attitudes if the plane's computer went berserk at a very high altitude.
                              I believe said pilots mentioned that idea more than once.

                              Comment


                              • #90
                                Originally posted by ATLcrew View Post
                                I believe said pilots mentioned that idea more than once.
                                Well, one ass-hat parlour talker noticed at least once and appreciated the insight.

                                But, For some reason, I have a mental image of Brick Tamland yelling "Loud Noises!".
                                Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                                Comment

                                Working...
                                X