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Engine Ignites Aboard Philippine Airlines Flight; Jet Lands Safely At LAX

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  • #16
    Originally posted by Evan View Post
    I don't think it's a matter of safety.
    It is a matter of SAFETY from the perspective that the FAA mandates that you HAVE to land at the CLOSEST airport IN TIME where a SAFE landing can be done. If yo had reasons to think that an overweight landing involves more SAFETY (not property) risk than keep flying on one engine, you would have an excuse to take extra time to burn or dump fuel instead of landing as soon as possible. However, I observed the same that you mentioned, that a lot of times after an IFSD the pilots do take extra time to burn or dump fuel instead of landing as soon as practical. That's why I looks to me lie almost a violation to the FAR.

    --- 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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    • #17
      Originally posted by flashcrash View Post

      Hmm ... isn't landing at over MLW unsafe by definition, at least in the purest sense of the word?

      Admittedly there's a lot of gray area to MLW, not least because it's often a design spec, rather than a number calculated from first principles (fuselage and wing flexing etc). And the "max" part does seem to be subject to some negotiation. For example, with enough incentive, aircraft manufacturers have been known to raise their initially declared MGLW a little if needs be.
      There is no grey area. The airplane is certified to land at MLW with a vertical speed of 600 ft/min and at MTOW with a vertical speed of 360 ft/min. Both requirements are in the same subpart of 14 CFR part 25 (see below). And it is a number calculated from structural analysis. Or rather, the structure is designed to be able to withstand the loads resulting from landing at those vertical speeds and wights.The MLW can be increased but if the design loads are exceeded you will have to reinforce the weakest parts of the structure and/or landing gear.

      As a side note, one fact that is usually not know, is that for many parts of the structure the loads caused by the landing at a given vertical speed are LOWER the heavier the weight (as long as the struts are not bottomed).

      § 25.473 Landing load conditions and assumptions.

      (a) For the landing conditions specified in § 25.479 to § 25.485 the airplane is assumed to contact the ground -

      (1) In the attitudes defined in § 25.479 and § 25.481;

      (2) With a limit descent velocity of 10 fps at the design landing weight (the maximum weight for landing conditions at maximum descent velocity); and

      (3) With a limit descent velocity of 6 fps at the design take-off weight (the maximum weight for landing conditions at a reduced descent velocity).

      --- 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


      • #18
        Originally posted by Gabriel View Post

        It is a matter of SAFETY from the perspective that the FAA mandates that you HAVE to land at the CLOSEST airport IN TIME where a SAFE landing can be done.
        What is the actual wording of the FAA mandate? It appears to me that this flight suffered a "locked-in" compressor stall, meaning it wasn't going to recover. That portends further damage if the engine is left running even at flight idle. We don't know how much vibration or other indications they were seeing. They apparently opted to leave it there and make an immediate return. Why is that safer than shutting it down, holding to jettison fuel and landing below MLW? (The odds of a second engine failure being highly remote).

        Don't get me wrong. If I was on that flight I'd be happy to land overweight asap...

        Comment


        • #19
          § 121.565 Engine inoperative: Landing; reporting.

          (a) Except as provided in paragraph (b) of this section, whenever an airplane engine fails or whenever an engine is shutdown to prevent possible damage, the pilot in command must land the airplane at the nearest suitable airport, in point of time, at which a safe landing can be made.

          (b) (c) [not relevant]

          (d) If the pilot in command lands at an airport other than the nearest suitable airport, in point of time, he or she shall (upon completing the trip) send a written report, in duplicate, to his or her director of operations stating the reasons for determining that the selection of an airport, other than the nearest airport, was as safe a course of action as landing at the nearest suitable airport. The director of operations shall, within 10 days after the pilot returns to his or her home base, send a copy of this report with the director of operation's comments to the responsible Flight Standards office.
          While the wording is not crystal clear in this regard, I submit that if because you decide to dump or burn fuel you end up landing say 1 hour later than you would have had you skipped that option, you are not landing at the nearest suitable airport in point of time, even f it is the same airport in both cases. If a SAFE landing could have been conducted without dumping / burning fuel, then wasting time dumping / burning fuel would be a violation of 14 CFR part 121.565 (a), at least that is my interpretation.

          Whether you decide to shut down the failed engine or leave it running at idle with occasional surges and bangs is an interesting question, but doesn't seem to me to be relevant to whether you should land ASAP or go for a fuel burning / dumping ride first.

          (The odds of a second engine failure being highly remote)
          .

          The odds of a DUAL engine failure are remote. The odds of a SECOND engine failure GIVEN that one engine has already failed is not more remote than the probability of an engine failure. The second engine doesn't know that the first engine has just failed as to lower its probability of failing. It's like the chances of getting 2 heads in a row are 1/4, but after you already got one head the chances of getting a second head are 50/50. In fact, the probability of a second engine failure is higher (not by much) than the normal probability of failure of an engine, given that it is possible (and there have been a few cases) that multiple engines can fail as a result of a common or subsequent cause, including for example fuel issues maintenance issues, increased power (and hence risk) on the remaining engine, or shutting down the wrong engine..

          Don't get me wrong. If I was on that flight I'd be happy to land overweight asap.
          I wonder why is that, but if that's the case then why not to do it? You are certainly not putting the slightly increased chance of a costly damage after an overweight landing on top of safety, are you?

          --- 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


          • #20
            Originally posted by Gabriel View Post

            While the wording is not crystal clear in this regard, I submit that if because you decide to dump or burn fuel you end up landing say 1 hour later than you would have had you skipped that option, you are not landing at the nearest suitable airport in point of time, even f it is the same airport in both cases. If a SAFE landing could have been conducted without dumping / burning fuel, then wasting time dumping / burning fuel would be a violation of 14 CFR part 121.565 (a), at least that is my interpretation.
            That certainly puts an interesting spin on it, but the stated directive is still for distance, not time. I would submit to you that, at any time during the fuel jettison process, should a problem with the remaining engine arise, you can always terminate that process and land asap, so the concern is still distance to the nearest suitable airport. During that entire hour of burning fuel, you are remaining in the same close proximity to the nearest suitable airport. Traversing to another field increases your distance to any suitable airport over a certain period of time.

            Whether you decide to shut down the failed engine or leave it running at idle with occasional surges and bangs is an interesting question, but doesn't seem to me to be relevant to whether you should land ASAP or go for a fuel burning / dumping ride first.
            The only relevance is that a 'locked-in' stall can be expected to continually damage the engine until it either fails or, worse, self destructs. The upside to leaving it running are less drag, less yaw and functional accessories. The downside danger probably outweighs this after a short period of time. Also, the continuous bangs and flame throwing is freaking out the pax, and I think that is a very valid (though not paramount) concern as well.

            I wonder why is that, but if that's the case then why not to do it? You are certainly not putting the slightly increased chance of a costly damage after an overweight landing on top of safety, are you?
            As I said, I have no personal objection to landing asap. Personally, no landing could be soon enough. But I do understand why that might not be the best option from the airline's point of view and (if the engine is shut down in a timely manner) it might not be significantly more dangerous to minimize the outcome for their precious assets. I think this is why these events are often followed by fuel burns or jettisons.

            One interesting thing is that they climbed to fuel-jettison altitude before returning. Perhaps not for that reason.

            I wonder if the engine should have not remained running in this case. Maybe ATL would weigh in on that...

            Comment


            • #21
              Originally posted by Evan View Post

              But is this really a scenario where an immediate return is necessary?

              [And several other posts questioning their actions and suggesting alternative actions]
              Home base: "The flight crew did wrong...the flight crew ALWAYS does wrong...I have a differing opinion...we must have more automation.."

              Seriously, man WHAT ELSE would you have them do?

              Yeah, Gabieeee points out they might have been overweight, but you are soooooooooooooooooooooooooooooooooooooooooooooooo blind over procedures that your mind is unable to comprehend why it might be good to land sorta expeditiously...

              The engine aint right...what if a bearing seizes, and/or it flings a blade or disk? What about those on-board fires where the plane burns up before you can land? What about that toxic lubricant leaking into the air intake system and dooming the passengers to a much slower (years) , but more painful death?

              Please note the HUGE GRAY AREA HERE:

              They did not haul over into an 80-degree bank to circle back and land downwind...they noted that there were engine problems, that flames were belching, they probably even consulted a QRH, or called maintenance or any number of things.

              "Hey, ATC, we need to come back and land and while we fully expect to live, we are declaring an emergency and call out the equipment, just to be on the safe side."

              They flew a pattern not_unlike a 172 shooting landings and landed in a rather normal manner so as not to introduce additional risks.

              Yeah, I see where you LATER thought through this, but the home base (Pilots suck) is clear, as usual.

              Indeed, physical punishment is in order.
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

              Comment


              • #22
                Gonna make some more popcorn and enjoy the diatribes. Without being the one in the cockpit, no way to really answer this. Way to many variables. If the Air Canada 78 with the cracked windshield went all the way back to LHR when it was over the top of Iceland, you have to wonder!

                Comment


                • #23
                  Originally posted by BoeingBobby View Post
                  Gonna make some more popcorn and enjoy the diatribes. Without being the one in the cockpit, no way to really answer this. Way to many variables. If the Air Canada 78 with the cracked windshield went all the way back to LHR when it was over the top of Iceland, you have to wonder!
                  Oh, but we MUST critically analyze every LAST detail of the pilot's actions. I certainly hope no one paused to itch their nether regions, that isn't on the checklist!
                  Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                  Comment


                  • #24
                    Originally posted by 3WE View Post

                    HUGE GRAY AREA HERE:
                    Colicky today? Just discussing a grey area and what might cause a crew to return asap (as this one did) vs burn/jettison fuel (as others have). Did that really throw you into a 72pt rage?

                    Comment


                    • #25
                      Originally posted by BoeingBobby View Post
                      Gonna make some more popcorn and enjoy the diatribes. Without being the one in the cockpit, no way to really answer this. Way to many variables. If the Air Canada 78 with the cracked windshield went all the way back to LHR when it was over the top of Iceland, you have to wonder!
                      Light on butter for me, please. Oh, and a Coke Zero, please and thank you.

                      Comment


                      • #26
                        Originally posted by Evan View Post
                        ... but the stated directive is still for distance, not time.
                        Is it? I am not a native English speaker, but...

                        § 121.565 Engine inoperative: Landing; reporting.

                        (a) Except as provided in paragraph (b) of this section, whenever an airplane engine fails or whenever an engine is shutdown to prevent possible damage, the pilot in command must land the airplane at the nearest suitable airport, in point of time, at which a safe landing can be made.
                        I would submit to you that, at any time during the fuel jettison process, should a problem with the remaining engine arise, you can always terminate that process and land asap, so the concern is still distance to the nearest suitable airport. During that entire hour of burning fuel, you are remaining in the same close proximity to the nearest suitable airport.
                        Within gliding distance? And even if yes, gliding a transport category aircraft still involves a lot of risks.

                        But I do understand why that might not be the best option from the airline's point of view and (if the engine is shut down in a timely manner) it might not be significantly more dangerous to minimize the outcome for their precious assets. I think this is why these events are often followed by fuel burns or jettisons.
                        Best option for the plane (i.e. for the $$$) and not significantly more dangerous for the persons? i side with the persons (and with you that don't want to waste time dumping fuel).
                        Nearest suitable airport, IN POINT OF TIME, at which a safe landing can be made.
                        So for me the question is just: Can a safe landing be made without dumping / burning fuel? If the answer is YES, then other options should be discarded unless they are deemed SAFER (not just not significantly more dangerous). Again, that's my point of view. The FAA, airlines and pilots don't seem to agree with me, and they probably have a good reason. I just fail to see 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 ---

                        Comment


                        • #27
                          Originally posted by ATLcrew View Post

                          Light on butter for me, please. Oh, and a Coke Zero, please and thank you.
                          Would you please comment on the amount of paperwork this might generate. I'd ass ume it's frightening.
                          Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                          Comment


                          • #28
                            Originally posted by Evan View Post

                            Colicky today? Just discussing a grey area and what might cause a crew to return asap (as this one did) vs burn/jettison fuel (as others have). Did that really throw you into a 72pt rage?
                            Colicky, no. Just amazed at how your disdain for pilots and your home base that they are always wrong, blinds you from seeing that 1) they didn't land immediately nor 2) they used good procedures and made good decisions...but, no, 72 pt font is no match for your closed mind.
                            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                            Comment


                            • #29
                              Originally posted by Gabriel View Post

                              IN POINT OF TIME
                              I am a native English speaker and I find that phrase hard to decipher. I suspect it was written by committee to be intentional vague.

                              It means nothing, grammatically. A "point of time" refers to a moment in time. Even dismissing the missing article, in "a moment in time" is meaningless there.

                              It could mean 'closest in terms of time' rather than 'closest in terms of distance', but that also seems meaningless.

                              What it doesn't say is "in the shortest possible span of time", "without delay", "as soon as possible" or "immediately", which is what you would expect there if that was the expressed directive.

                              I think it's left open to pilot judgment, as long as the pilot doesn't stray from the nearest suitable airport.

                              And, again, I agree with you on landing asap if there is no reason not to. But the question I'm asking (what 3WE calls 'disdain') is why pilots often don't do this. I suspect it might have something to do with the relative safety of single engine ops near the runway and the wisdom of stabilizing and taking your time to do everything methodically and correct. But it is puzzling...

                              Comment


                              • #30
                                Originally posted by Gabriel View Post
                                IN POINT OF TIME
                                Quoting... ahem... Heidegger... (which I rarely do on this forum): "What is incalculably far from us in point of distance can be near to us."

                                He is supplanting the word 'terms' with the word 'point'. Of course he is doing this in archaic language, but it stands to reason then that 'in point of time' is synonymous with 'in terms of time'.

                                I suppose someone at the FAA could have had a fetish for old-timey diction...

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