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

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  • ATLcrew
    replied
    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.

    Leave a comment:


  • Evan
    replied
    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?

    Leave a comment:


  • 3WE
    replied
    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!

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  • BoeingBobby
    replied
    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!

    Leave a comment:


  • 3WE
    replied
    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.

    Leave a comment:


  • Evan
    replied
    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...

    Leave a comment:


  • Gabriel
    replied
    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?

    Leave a comment:


  • Evan
    replied
    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...

    Leave a comment:


  • Gabriel
    replied
    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).

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  • Gabriel
    replied
    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.

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  • Evan
    replied
    Originally posted by Gabriel View Post

    Yes, I never understood that. It even looks to me like a violation of requirement to land at the closest suitable field where a safe landing can be performed... So unless you consider an over-MLW landing unsafe... which I don't see why you would...
    I don't think it's a matter of safety. I think it's about preserving the company assets. The FAA requires the gear to be capable of a MTOW landing while touching down at 360ft/min (vs MLW up to 600ft/min). There are other issues such as fuselage bending and forces on the fuel-laden wing structures, but I assume that's all calc'd in as well. There's the higher Vref (about 15kts higher I think for a 777) which will usually still allow for full landing flaps and there's braking performance (brake overheating and potential for brake fade) and the need for about 1000' feet of extra runway (but any runway you took off from will have that).

    I'm guessing the overweight landing inspection is not a major concern when you're going to have to swap out an engine anyway...

    Leave a comment:


  • flashcrash
    replied
    Originally posted by Gabriel View Post
    ... unless you consider an over-MLW landing unsafe... which I don't see why you would...
    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.

    Leave a comment:


  • Gabriel
    replied
    Originally posted by Evan View Post
    land at the closest suitable airport, but if landing at MTOW is no big deal, then why are such incidents often followed by level-off and fuel-dumping/burning before returning?
    Yes, I never understood that. It even looks to me like a violation of requirement to land at the closest suitable field where a safe landing can be performed... So unless you consider an over-MLW landing unsafe... which I don't see why you would...

    Leave a comment:


  • Evan
    replied
    Originally posted by ATLcrew View Post

    I don't.
    But is this really a scenario where an immediate return is necessary? Certainly a fire outside the engine core could dictate that, but this was, as far as I can tell, a case of internal engine damage only, where the engine can always be shut down to eliminate any threat to the aircraft. I agree with Gabriel - land at the closest suitable airport, but if landing at MTOW is no big deal, then why are such incidents often followed by level-off and fuel-dumping/burning before returning?

    Leave a comment:


  • Gabriel
    replied
    I agree with ATL. Engine failure in a twin = land at closest suitable airport, Planes are certified for landing at MTOW. If done right the overweight landing inspection is limited to checking the landing Gs in the QAR or similar.

    Leave a comment:

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