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Before the PIA 8303 debacle, there was Vietnam VN-781

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  • Before the PIA 8303 debacle, there was Vietnam VN-781

    File this under lessons not learned I guess. Unstable approaches remain a major cause of accidents but one possible consequence is failure to configure the landing gear. In this case, ATC was adding workload by requesting that VN-781 disregard the standard STAR speed restrictions and expedite the approach (at their discretion but at the risk of losing favor in a competitive airspace). Somewhere along the way the before-landing checklist either got skipped or degraded, as did CRM. A controller at a nearby field observed that the gear was not down and warned Melbourne tower, who then warned the crew but the message was misunderstood. This being a 787, the CONFIG GEAR master warning triggered when descending below 800ft, by which time the PF chose to go-around. Alls well that ends well. And then, six months later, PIA 8303 ends very unwell.

    Aviation Herald - News, Incidents and Accidents in Aviation


    Aviation Herald - News, Incidents and Accidents in Aviation

  • #2
    There is an old saying, "There are those that have and those that will." Luckily, I never did, and the only thing I fly now has the gear down and welded. Hard to imagine putting a jet on it's belly accidentally now. So many bells,whistles, lights and horns.

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    • #3
      Originally posted by Evan View Post
      File this under lessons not learned I guess. Unstable approaches remain a major cause of accidents but one possible consequence is failure to configure the landing gear. In this case, ATC was adding workload by requesting that VN-781 disregard the standard STAR speed restrictions and expedite the approach (at their discretion but at the risk of losing favor in a competitive airspace). Somewhere along the way the before-landing checklist either got skipped or degraded, as did CRM. A controller at a nearby field observed that the gear was not down and warned Melbourne tower, who then warned the crew but the message was misunderstood. This being a 787, the CONFIG GEAR master warning triggered when descending below 800ft, by which time the PF chose to go-around. Alls well that ends well. And then, six months later, PIA 8303 ends very unwell.

      Aviation Herald - News, Incidents and Accidents in Aviation


      https://avherald.com/h?article=4d7a6e9a&opt=0
      I am not sure why you call this a "lesson not learned". Unstable approaches followed by go-arounds (as they should) happen quite frequently

      as the aircraft descended through 580 ft AFE at 183 kt with flaps-5 and the landing gear up
      The approach was unsterilized in many ways. The plane was not configured for landing (neither flaps nor gear), the speed was way too high for their altitude and distance to the runway, and likely they had not completed the landing checklist yet.

      We will never know it, but it is possible that the captain (who was also the pilot flying), who had already requested the FO to continue configuring the plane for landing, had already been mentally preparing for going around since the stabilized approach gate of 500ft above the runway was quickly approaching and stabilizing the approach by then was becoming increasingly impossible.

      That is why when...

      the crew received a master warning alert with an associated ‘CONFIG GEAR’ message. In response, the PM moved the landing gear handle to the down position
      ... instead, ...

      the PF announced ‘go-around’
      This can be an example of a crew failing to manage the energy in the final approach (can happen to anyone) BUT at the same time an example of a captain that is fully into the game using good judgement and following procedures, rather than a "lesson not learned".

      Or, maybe they didn't care about checklists, they forgot the gear up, they had the full intention to salvage the approach, and the only thing that took them apart from PIA is that the captain decided to go around only because he realized they had forgotten the gear up thanks to the master warning and gear EICAS message.

      --- 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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      • #4
        Originally posted by BoeingBobby View Post
        There is an old saying, "There are those that have and those that will." Luckily, I never did, and the only thing I fly now has the gear down and welded.
        Beware of overconfidence. It was not a J3 but a PA-11. It landed gear up (or rather, the gear folded up when they cut the gear tensor rod, or whatever the lower side of the triangle is called)

        Hard to imagine putting a jet on it's belly accidentally now. So many bells, whistles, lights and horns.
        Thanks to the PIA pilots, we don't need to imagine 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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        • #5
          Originally posted by Gabriel View Post

          I am not sure why you call this a "lesson not learned".

          This can be an example of a crew failing to manage the energy in the final approach (can happen to anyone) BUT at the same time an example of a captain that is fully into the game using good judgement and following procedures, rather than a "lesson not learned".
          I call it a lesson not learned because VN-781 clearly demonstrated how, due to the human factors that arise during an unstabilized approach, even the most modern 21st-century airliner can get down to final—around 30 seconds prior to touchdown!—with the gear still stowed and forgotten, and therefore possibly land in that condition. That was the lesson: there's more to be concerned about than hard landings and tail strikes and runway excursions.

          A certain roguish culture at PIA might have learned from that, as well as plenty of other cultures that still inspire overconfident, reckless and undisciplined airmanship. In short, this incident should have been widely reported and taken much more seriously.

          (BTW, the go-around was no longer an option at the point of the gear warning. The main gear on a 787 takes over 30 seconds to transit.)

          Of course, nobody (least of all myself) would have ever envisioned the possibility of a go-around after landing without gear... as far as I known, that was a first.

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          • #6
            Originally posted by BoeingBobby View Post
            There is an old saying, "There are those that have and those that will." Luckily, I never did, and the only thing I fly now has the gear down and welded. Hard to imagine putting a jet on it's belly accidentally now. So many bells,whistles, lights and horns.
            How old is that saying? I can't fathom how this would happen now that the gear lever is placed distinctly apart from the flaps lever and involves three green indicators and a checklist to verify them by. Unless that checklist goes out the window. Are two qualified pilots going to skip that? If so, is there a warning for BAR TOO LOW?

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            • #7
              Originally posted by Evan View Post
              the most modern 21st-century airliner can get down to final—around 30 seconds prior to touchdown!—with the gear still stowed and forgotten
              Not necessarily forgotten. They may have just not got to that point in the flow so far. They still hade flaps 5, maybe the SOP in the airline is to lower the gear after say flaps 15 or something.

              For example, I once talked with an airline instructor who told me that, to avoid forgetting to perform the landing checklist, he didn't use a "Gear down" call but a "Gear down and landing checklist please" call. If that comes after say flaps 15, it is totally understandable that they had not lowered the gear and had not run the landing checklist yet. They were way behind the plane, the approach was way unstabilized, and the captain called a go around before the stabilized approach gate. Yes, he called it after the master warning, but perhaps he was about to call it anyway and the master warning just anticipated it a couple of seconds.

              OR... they may have forgotten the gear up and disregarded the checklist. Again, I don't have enough info to tell one way or another.

              and therefore possibly land in that condition.
              There were several layers of swiss cheese yet. The master warning (which worked), the GPWS warning, the stabilized approach criteria and the checklist.
              All these layers were present in PIA too, and the crew ignored ALL of them, which is outrageous.

              That was the lesson: there's more to be concerned about than hard landings and tail strikes and runway excursions.
              Ok, because a crew that doesn't care about landing hard, landing short, landing long, running out of the runway, stalling, or hitting an obstacle will say "screw all that, but we risk landing gear up so we better respect the stabilized approach criteria"

              --- 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


              • #8
                Originally posted by Evan View Post
                Of course, nobody (least of all myself) would have ever envisioned the possibility of a go-around after landing without gear... as far as I known, that was a first.
                It was Not_.
                (Go-around was called before touchdown, but still...)
                "I know that at times I can be a little over the top." -ITS

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                • #9
                  Originally posted by Not_Karl View Post
                  It was Not_.
                  (Go-around was called before touchdown, but still...)
                  Interesting… The TU-154 seems to be designed in a way that is more survivable during a gear-up landing. Still, in this case, the go-around decision was made before the landing.

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                  • #10
                    Originally posted by Gabriel View Post
                    Ok, because a crew that doesn't care about landing hard, landing short, landing long, running out of the runway, stalling, or hitting an obstacle will say "screw all that, but we risk landing gear up so we better respect the stabilized approach criteria"
                    Ha, wouldn’t that be nice... A crew that disrespects the stable approach criteria is going to do so habitually. Such pilots are quite confident that they possess the skills to avoid all of the outcomes you mentioned. The lesson is humility in the human factor of forgetfulness and neglect with regard to a potentially fatal failure to configure the gear for landing. Skill won’t save you there.

                    Also, I think such pilots are more concerned with making embarrassing and stupid (and costly) errors than with causing fatal accidents.

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