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Icelandicair missed approach

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  • Icelandicair missed approach

    So they missed the first approach at Manchester, then missed the approach into Liverpool, finally returning to Manchester with low fuel.

    The issue was turbulence and low level wind shear. My experience is from old DC-8's and 747's. As I recall happening only a few times, with the auto-pilot connected and an ILS approach, the control column was wiping back and forth so violently you were afraid to touch or hold the control wheel for fear of breaking your wrist. I reached up and disconnected the autopilot with the on/off switch. Hand flying you could let the wings bank a little and then correct back to level and it didn't feel quite so violent. Now maybe newer aircraft, the B-757, didn't react that violently, I don't know.

    I do remember two instances in my career that wind shear was not expected and could have been bad. Landing in Pago Pago for fuel in the 747 the radar altimeter said 50 then 10. I yanked back on the wheel and went to full power. The touchdown was smooth and immediately went to idle and reverse, lucky. Then 15 years later landing at Deer Valley Az. near Phoenix in the Citation X, same deal at 50ft the bottom dropped out and it was yank back and full power. Again luckily a smooth touchdown.

  • #2
    On the 74, does the thrust come on quickly enough to make a difference at 10ft? I get the pitch inputs to arrest the sink. Aren't they enough?

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    • #3
      Good question. It happens in the blink of a eye so hard to tell. Just a reaction.

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      • #4
        Somehow relevant. 0:25

        https://youtu.be/P49OxVqOvec?t=25

        --- 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 ---

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        • #5
          Originally posted by kent olsen View Post
          Icelandicair missed approach

          So they missed the first approach at Manchester, then missed the approach into Liverpool, finally returning to Manchester with low fuel.
          Any link? I could not find it in AvHerald.

          --- 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 ---

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          • #6
            Originally posted by Gabriel View Post
            Somehow relevant. 0:25

            https://youtu.be/P49OxVqOvec?t=25
            The A320? I think that's a go around. You hear the priority take over just at the end of it. I expect the F/O came out of that with tail between legs.

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            • #7
              Originally posted by Evan View Post

              The A320? I think that's a go around. You hear the priority take over just at the end of it. I expect the F/O came out of that with tail between legs.
              Yes, you can see the "and fell" the pitch decreasing and the sink rate increasing, an between 30 and 20 ft the FO (who is the PF) retards the throttles (as per SOP) but the captain immediately slams them full forward and pitches up, initiating the go-around but the plane still touches down quite hard before starting to climb again. Unfortunately the video lacks enough quality to see the variation in vertical speed, but you can listen how the "fifty, forty. thirty, twenty" happens at increased pace.

              --- 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 ---

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              • #8
                Originally posted by Gabriel View Post

                Yes, you can see the "and fell" the pitch decreasing and the sink rate increasing, an between 30 and 20 ft the FO (who is the PF) retards the throttles (as per SOP) but the captain immediately slams them full forward and pitches up, initiating the go-around but the plane still touches down quite hard before starting to climb again.
                Well, here is one instance of a disadvantage to sidestick control. The thrust is going to take some seconds to have any effect and Immediate pitch input is needed. But even if the CPT commands full aft stick, the system will only add his input algebraically, so full elevator response is not possible. The priority takeover also takes time to latch. The FCOM recommends holding the button down for 40 seconds! But the CPT in this case probably didn't add pitch input immediately because we don't hear a "dual input" aural warning. Therefore, nothing he does at that point can prevent a hard touchdown.


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                • #9
                  aviation.safety.net

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                  • #10
                    Originally posted by Evan View Post

                    Well, here is one instance of a disadvantage to sidestick control. The thrust is going to take some seconds to have any effect and Immediate pitch input is needed. But even if the CPT commands full aft stick, the system will only add his input algebraically, so full elevator response is not possible. The priority takeover also takes time to latch. The FCOM recommends holding the button down for 40 seconds! But the CPT in this case probably didn't add pitch input immediately because we don't hear a "dual input" aural warning. Therefore, nothing he does at that point can prevent a hard touchdown.

                    Yet, you can see the plane quickly pitching up just before the slam. It's hard to tell from the camera because it is moving so much, but look at the AIs.
                    It looks like the touchdown would have been much harder hadn't the captain intervened wit pitch-up inputs. Firewalling the throttles probably had nothing to do with the vertical speed at touchdown but for sure adding thrust early helps in a safer and more positive go-around.

                    --- 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 ---

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                    • #11
                      Originally posted by Gabriel View Post

                      Yet, you can see the plane quickly pitching up just before the slam. It's hard to tell from the camera because it is moving so much, but look at the AIs.
                      It looks like the touchdown would have been much harder hadn't the captain intervened wit pitch-up inputs. Firewalling the throttles probably had nothing to do with the vertical speed at touchdown but for sure adding thrust early helps in a safer and more positive go-around.
                      In a go-around, certainly.

                      I think the pitch increase must have come from the F/O, beginning to flare with the intention to land. If the CPT had added pitch before taking priority, we would hear a dual input warning (unless that is inhibited by the EGPWS callouts).

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                      • #12
                        Originally posted by Evan View Post

                        In a go-around, certainly.

                        I think the pitch increase must have come from the F/O, beginning to flare with the intention to land. If the CPT had added pitch before taking priority, we would hear a dual input warning (unless that is inhibited by the EGPWS callouts).
                        And this was a go around and Kent was also talking of go around. Nobody in their right mind adds toga thrust and pitches up a few feet and a couple of seconds before a hard touchdown with the intention of landing.

                        I cannot completely understand what is going on there but I very much doubt that a captain will tear the throttle levers from his FO's hands who had just retarded them, fire wall them, and not also start manipulating the stick. If you take over, you take over. You don't just take over the thrust levers. Because of that, I am pretty confident that the captain was making stick inputs during that 1.5 seconds between the throttle take over and the slam and at minimum contributed to increase the pitch (even if the input was averaged with the FOs).

                        Now, lack of dual input and priority left that came only after the slam.... First of all, again, it was like 1.5 seconds between the the throttle take over and the slam. I don't know how quickly the dual input alarm will sound after the first stick input. And the same for the priority left one, that we do hear at the end of the clip (well, we just hear "priority" before the end of the clip, but I guess there is little doubt that the "left" would have come immediately afterwards.

                        About the 40 seconds.... there was a strange logic with this priority button which I don't remember very well, but it was a battle of buttons where the last one to depress it had priority until someone had depressed it for X (perhaps 40?) seconds than the priority would "stick" with his side. But when you depress the priority button all the control goes to your side and the inputs of the other stick are ignored, so there is no dual input. So perhaps the captain immediately, together with the throttle levers, started to make stick inputs with the priority button depressed but the priority call took almost 2 seconds for some reason (like the GPWS count or the retard call having priority)

                        --- 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 ---

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                        • #13
                          Originally posted by kent olsen View Post
                          aviation.safety.net
                          Looked it up by airline (any airline in Iceland) and by country (United Kingdom) and could not find it.

                          --- 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 ---

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                          • #14
                            Originally posted by Gabriel View Post

                            And this was a go around and Kent was also talking of go around. Nobody in their right mind adds toga thrust and pitches up a few feet and a couple of seconds before a hard touchdown with the intention of landing.
                            Kent is describing two continued landings.

                            Originally posted by Gabriel View Post
                            I cannot completely understand what is going on there but I very much doubt that a captain will tear the throttle levers from his FO's hands who had just retarded them, fire wall them, and not also start manipulating the stick. If you take over, you take over. You don't just take over the thrust levers. Because of that, I am pretty confident that the captain was making stick inputs during that 1.5 seconds between the throttle take over and the slam and at minimum contributed to increase the pitch (even if the input was averaged with the FOs).

                            Now, lack of dual input and priority left that came only after the slam.... First of all, again, it was like 1.5 seconds between the the throttle take over and the slam. I don't know how quickly the dual input alarm will sound after the first stick input. And the same for the priority left one, that we do hear at the end of the clip (well, we just hear "priority" before the end of the clip, but I guess there is little doubt that the "left" would have come immediately afterwards.

                            About the 40 seconds.... there was a strange logic with this priority button which I don't remember very well, but it was a battle of buttons where the last one to depress it had priority until someone had depressed it for X (perhaps 40?) seconds than the priority would "stick" with his side. But when you depress the priority button all the control goes to your side and the inputs of the other stick are ignored, so there is no dual input. So perhaps the captain immediately, together with the throttle levers, started to make stick inputs with the priority button depressed but the priority call took almost 2 seconds for some reason (like the GPWS count or the retard call having priority)
                            The DUAL INPUT has the lowest priority level of the synthetic voice warnings. I think EGPWS or RETARD would have inhibited it here. Hence the importance of calling out the takeover verbally (and the go around). PRIORITY LEFT is delayed by about one second from what I've seen, but perhaps it was also further delayed due to EGPWS and priority level.

                            I can't see detail in the video well enough, but if there was any dual input, you would immediately see the CPT priority light flashing.

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                            • #15
                              When I read about all of this, I am glad that A: I'm retired and B: I never flew the Airbus

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