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

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  • #31
    Originally posted by Evan View Post

    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.
    I don't like the wording either, but what else could "the nearest suitable airport, in point of time" mean? Have you heard of the "near future"?

    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...
    One thing is to take your time to stabilize and and do everything methodically and correct (i.e. without rushing or cutting corners). Another is stabilize, do everything methodically and correct, and THEN fly another hour to burn or dump fuel. I must be missing something, but look at this example. They landed about 40 minutes after the mayday, instead of say 10 to 15 minutes. They went out to about 100 miles from the airport (at 10,000 ft) instead of staying within 40 miles (if they had completed the return without dumping they apparently intended initially). I and trust these guys!

    https://www.youtube.com/watch?v=zilMT9M1yoM

    --- 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


    • #32
      Originally posted by Gabriel View Post

      I don't like the wording either, but what else could "the nearest suitable airport, in point of time" mean? Have you heard of the "near future"?
      I'm quite convinced that it means "the nearest suitable airport in terms of time". That last part is, of course, redundant unless you are in a mountainous area below the surrounding MSA. Perhaps that is why it is added. I take it to mean "stay close to the airport in case an immediate landing becomes necessary" (as opposed to "land immediately"). The wording suggests it might have been carried over from the early days of aviation (such as the use of the word 'field' in reference to modern airports).

      One thing is to take your time to stabilize and and do everything methodically and correct (i.e. without rushing or cutting corners). Another is stabilize, do everything methodically and correct, and THEN fly another hour to burn or dump fuel. I must be missing something, but look at this example. They landed about 40 minutes after the mayday, instead of say 10 to 15 minutes. They went out to about 100 miles from the airport (at 10,000 ft) instead of staying within 40 miles (if they had completed the return without dumping they apparently intended initially). I and trust these guys!

      https://www.youtube.com/watch?v=zilMT9M1yoM
      It definitely shows the confidence of the crew and the controller in the reliability of the second engine. Sending them off the holding pattern was probably due to traffic (we can't be dumping fuel on other aircraft). Correct me on this, but I think you need about 4000' of vertical separation and about 1nm of lateral seperation per 1000' of that vertical separation to assure complete evaporation.

      I also assume that by the time the crew accepted the option to dump fuel, they had shut down the affected engine and determined that no fire was present.

      Comment


      • #33
        Originally posted by Evan View Post

        I'm quite convinced that it means "the nearest suitable airport in terms of time".

        That last part is, or course redundant unless you are in a mountainous area below the surrounding MSA.
        No, it is not redundant. You can have an airport 30 miles ahead and another one 10 miles back. If you can shoot a straight-in final for the one 30 miles ahead but for the one that is 10 miles back you need to first turn 180 degrees, then fly a downwind, base leg and final, you will probably land much sooner in the one that is 30 miles ahead. If you have one airport 10 miles from you in IMC requiring a full instrument procedure, and another one 30 miles from you that is visual, you can probably land sooner in the one that is 30 miles away. If you have one airport that is 10 miles from you but you are at 39000 ft, you will need to fly more than 100 miles anyway to get down. Etcetera.

        Actually I think that the "in point of time" is a relatively modern addition, not the original wording of the rule, which was added precisely to mean that you don;t need to land at the airport that is the closest if you can land at another airport sooner on in the same time.

        --- 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


        • #34
          Originally posted by Gabriel View Post

          No, it is not redundant. You can have an airport 30 miles ahead and another one 10 miles back. If you can shoot a straight-in final for the one 30 miles ahead but for the one that is 10 miles back you need to first turn 180 degrees, then fly a downwind, base leg and final, you will probably land much sooner in the one that is 30 miles ahead. If you have one airport 10 miles from you in IMC requiring a full instrument procedure, and another one 30 miles from you that is visual, you can probably land sooner in the one that is 30 miles away. If you have one airport that is 10 miles from you but you are at 39000 ft, you will need to fly more than 100 miles anyway to get down. Etcetera.

          Actually I think that the "in point of time" is a relatively modern addition, not the original wording of the rule, which was added precisely to mean that you don;t need to land at the airport that is the closest if you can land at another airport sooner on in the same time.
          Indeed. I hadn't considered those things. But I think we can now agree that the FAR's does not require an immediate return after a single engine failure on a multi-engine aircraft. It merely requires designating your return/diversion the closest suitable airport in terms of time. So, you can go in asap or you can hold to burn/jettison fuel as long as you ultimately land at the closest suitable airport in point of time from the location where the failure occurred. This assures that, at any time during the hold, you remain in proximity to the closest suitable airport as opposed to increasing the distance to the closest suitable airport by burning fuel while traversing to another one.

          Comment


          • #35
            Originally posted by Evan View Post

            Indeed. I hadn't considered those things. But I think we can now agree that the FAR's does not require an immediate return after a single engine failure on a multi-engine aircraft. It merely requires designating your return/diversion the closest suitable airport in terms of time. So, you can go in asap or you can hold to burn/jettison fuel as long as you ultimately land at the closest suitable airport in point of time from the location where the failure occurred. This assures that, at any time during the hold, you remain in proximity to the closest suitable airport as opposed to increasing the distance to the closest suitable airport by burning fuel while traversing to another one.
            What is "in proximity"? A certain distance? A certain time away? Gliding distance? Did El Al remain "in proximity"?

            I don't know what the exact intent of the rule is. But I will tell you one thing: My confidence in a safe outcome is very high in either way, but not equally high. Remaining in "close proximity to the airport" doesn't increase significantly my confidence in a safe outcome. Landing ASAP* (even above MLW) would.

            * (ASAP includes all the provisions for stabilizing, running required checklists, securing the cabin, and flying a reasonable non-aerobatic approach)

            --- 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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            • #36
              The first bowl is empty, but I have plenty un-popped in the pantry. You all are very entertaining, but have no f'n clue! ATL not included.

              Comment


              • #37
                Originally posted by Gabriel View Post

                What is "in proximity"? A certain distance? A certain time away? Gliding distance? Did El Al remain "in proximity"?
                Well, if you aren't making an immediate return, I guess that's up to ATC (they can't have you dumping fuel on other traffic). But the closest suitable ATC...

                Comment


                • #38
                  Originally posted by Gabriel View Post
                  One thing is to take your time to stabilize and and do everything methodically and correct (i.e. without rushing or cutting corners). Another is stabilize, do everything methodically and correct, and THEN fly another hour to burn or dump fuel. I must be missing something, but look at this example. They landed about 40 minutes after the mayday, instead of say 10 to 15 minutes. They went out to about 100 miles from the airport (at 10,000 ft) instead of staying within 40 miles (if they had completed the return without dumping they apparently intended initially). I and trust these guys!
                  BTW, I'm not saying this doesn't bother me. If they were at 10,000, I'm guessing they could glide about 25nm at best. But engines usually show some signs of trouble before conking out completely. Sure, a coincidental catastrophic failure of the remaining engine could hypothetically occur. Then what do you do? Or a meteor, of course...

                  Comment


                  • #39
                    Originally posted by Evan View Post
                    But engines usually show some signs of trouble before conking out completely.
                    Are you sure? I am not, either way. But I am sure that many (not necessarily most) engine failures happen with no or little warning.

                    Sure, a coincidental catastrophic failure of the remaining engine could hypothetically occur. Then what do you do? Or a meteor, of course...
                    "Coincidental" means just that they happen together but it doesn't say anything about independence of events. The failure of the second engine can (and has always been proven to be) be much ore than just "coincidental".

                    I am not aware of a single case where 2 turbine engines failed randomly and independently of each other. In all the cases that I know both failures were correlated by a common or consequential cause. Fuel starvation, fuel exhaustion, fuel contamination, flying pieces of an engine (or the whole engine) hitting the other engine, volcanic ashes, birds, severe water injection, severe hail damage, fuel frozen, ice clogging of the oil-fuel heat exchanger, same maintenance mistake done on multiple engines, shutting down the wrong engine, and overstressing the remaining engine. As I said before, if the probability of an engine to fail is X, the probability of a second engine to fail once the first one already failed is much greater than X. Still very very low, but not nearly as low as just a random engine failure.And much more likely than a meteor.

                    --- 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


                    • #40
                      Originally posted by Gabriel View Post

                      I am not aware of a single case where 2 turbine engines failed randomly and independently of each other. In all the cases that I know both failures were correlated by a common or consequential cause. Fuel starvation, fuel exhaustion, fuel contamination, flying pieces of an engine (or the whole engine) hitting the other engine, volcanic ashes, birds, severe water injection, severe hail damage, fuel frozen, ice clogging of the oil-fuel heat exchanger, same maintenance mistake done on multiple engines, shutting down the wrong engine, and overstressing the remaining engine. As I said before, if the probability of an engine to fail is X, the probability of a second engine to fail once the first one already failed is much greater than X. Still very very low, but not nearly as low as just a random engine failure.And much more likely than a meteor.
                      Most of those causes you listed would have the engines failing either simultanously or within minutes of one another. Context is important here. If you have a non-recoverable engine stall in one engine while the other shows no signs of trouble over a number of minutes as you are working the problem, there is a very low chance that the second engine will fail. You have to take that into account. Again, I don't like the idea of straying too far from a runway with no propulsion redundancy, but I also acknowledge that the risk in doing so is quite remote.

                      But, as you insist that landing over MLW is of no real concern, I have to question the wisdom of not doing so.

                      Comment


                      • #41
                        As I have said many times in other posts that the three big posters, Evan, Gabriel and 3, constantly try and analyze. You have no f'n clue to how the real world works when YOU are the one sitting in the seat. An overweight landing can be a big problem. As I understand it, some if not most of the fuse plugs went after his landing. Rims damaged? Brakes? Chief pilot not going to be real happy with a couple of hundred thousand dollars in repairs if not completely necessary. Lets start with this one and then we will talk shortly about the Air Canada flight a few days later with the cracked windshield. First, MAYDAY is for a flight about to go down, NOT for an engine failure in a multi-engine aircraft that is still capable of maintaining flight. Usual scenario after the check lists have been run, ask for a location to hold and dump fuel down to max landing weight. NOW we get on the radio or the SATCOM and call the company. What do THEY want you to do? Has a lot of bearing on what action you take next. This brings me to the Air Canada fight. They were already East of Iceland. From what I saw on a Flight Aware track that somebody posted, it looks like they did a turn in a hold over Iceland, and then went back to LHR. I would bet a couple of thousand dollars that while they were in the hold they contacted the company and were TOLD to return to LHR where they have a maintenance base and probably spares. Any of these situations can ALWAYS be challenged by the Captain depending on the situation. WITHOUT being in the seat, all of Evans wiki info and all of Gabriels engineering math calculations and drawings don't mean a G.D. thing! Gabe, you can keep that signature on the bottom of your page until long after I am dead and gone, you have no idea what it's like, and until you have ever been one of the flight crew on a transport category aircraft, you never will! Happy Thanksgiving to all.

                        Comment


                        • #42
                          Originally posted by BoeingBobby View Post
                          As I have said many times in other posts that the three big posters, Evan, Gabriel and 3, constantly try and analyze. You have no f'n clue to how the real world works when YOU are the one sitting in the seat. An overweight landing can be a big problem. As I understand it, some if not most of the fuse plugs went after his landing. Rims damaged? Brakes? Chief pilot not going to be real happy with a couple of hundred thousand dollars in repairs if not completely necessary. Lets start with this one and then we will talk shortly about the Air Canada flight a few days later with the cracked windshield. First, MAYDAY is for a flight about to go down, NOT for an engine failure in a multi-engine aircraft that is still capable of maintaining flight. Usual scenario after the check lists have been run, ask for a location to hold and dump fuel down to max landing weight. NOW we get on the radio or the SATCOM and call the company. What do THEY want you to do? Has a lot of bearing on what action you take next. This brings me to the Air Canada fight. They were already East of Iceland. From what I saw on a Flight Aware track that somebody posted, it looks like they did a turn in a hold over Iceland, and then went back to LHR. I would bet a couple of thousand dollars that while they were in the hold they contacted the company and were TOLD to return to LHR where they have a maintenance base and probably spares. Any of these situations can ALWAYS be challenged by the Captain depending on the situation. WITHOUT being in the seat, all of Evans wiki info and all of Gabriels engineering math calculations and drawings don't mean a G.D. thing! Gabe, you can keep that signature on the bottom of you page until long after I am dead and gone, you have no idea what it's like, and until you have ever been one of the flight crew on a transport category aircraft, you never will! Happy Thanksgiving to all.
                          It's always nice when you actually give us something. Happy Thanksgiving.

                          What effect does a rotating or locked-in stall have on this, where the engine is still running but damaged and not going to recover and will eventually either seize or self-destruct? I'm curious because I've never seen anything like the video posted on this incident showing what appears to be final approach with the #1 engine clearly still surging and ejecting flames out the intake. Wouldn't you normally shut that down at some point?

                          Comment


                          • #43
                            Originally posted by Evan View Post

                            It's always nice when you actually give us something. Happy Thanksgiving.

                            What effect does a rotating or locked-in stall have on this, where the engine is still running but damaged and not going to recover and will eventually either seize or self-destruct? I'm curious because I've never seen anything like the video posted on this incident showing what appears to be final approach with the #1 engine clearly still surging and ejecting flames out the intake. Wouldn't you normally shut that down at some point?
                            Still producing thrust? One compressor stall after another? If you weren't in the seat, you can second guess all day. However, Mayday, Mayday, Mayday was uncalled for in my opinion, but I was not in the seat.

                            Comment


                            • #44
                              Hey BB, actually I agree with you more than you think. I said that I must be missing something and that they probably have a good reason to weight towards keep flying and burn or dump fuel vs landing ASAP. You said "You have no f'n clue to how the real world works when YOU are the one sitting in the seat". Kinda in the same line, isn't it?

                              That's why we (or at least I) value the interaction with the transport category pilots in the forum, you bring a good dose of reality to our outsider's speculation.
                              Now, that I value i doesn't mean that I will always agree ot that you will convince me with "because I say so and I know better than you". Which brings us to my signature.

                              In the post above, you did not impose your credentials. You didn't expect us (or at least me) to just surrender under your authority and believe at face value anything you said just because you said it and you are YOU, the one who knows. And you did NOT do that in the post above.

                              You explained things, you disclosed how things work in the real world. You brought the braking issue that I had not considered (I was focused on the touchdown loads). the potential maintenance cost that can be incurred in such landing, the "pressure" that the pilots have to avoid such cost (which is a reasonable pressure and something that the pilot will have to weight into his decision making), and the consulting with operations, dispatch, maintenance etc as part of the decision making.

                              If you ask me, this was a great contribution by you and happens to be totally in line with my signature.

                              I still have doubts or questions, and one of the biggest ones is whether that FAR that I cited above should be improved. I am ok with your explanation and that in a case where the pilot is very confident that the failure of the the engine is independent of the other engine (and as Evan said an engine surging is very unlikely to be related to anything happening with the other engine) the risk of a second engine failing is very remote and hence go ahead, take costs and other business concerns into account, burn/dump fuel and save money and time of AOG for the company. However, the FAR doesn't say anything about that. If that is a reasonable and acceptable course of action, as it seems to be, then the FAR should reflect that instead of calling to just "land at the closest suitable airport in point of time where a safe landing can be accomplished".

                              Thank you for your previous post and happy Thanksgiving.

                              --- 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


                              • #45
                                Originally posted by BoeingBobby View Post
                                However, Mayday, Mayday, Mayday was uncalled for in my opinion, but I was not in the seat.
                                I think that at least for some operators it is their SOP to declare emergency when an engine fails in a twin. So perhaps the pilot was just following his company's SOP by declaring emergency.
                                That doesn't answer your point though, it just moves the goalpost. Perhaps what is uncalled for is not the the pilot declared emergency but that the SOP is to declare emergency.

                                In any event, always biased towards safety, better to declare an unnecessary emergency than not to declare a necessary one. At least you will get the full attention from ATC, get fast routing/clearing, and be approved for anything you need. In a twin you cannot afford loosing a second engine, so the FAR requirement is landing at the nearest suitable airport in point of time (as opposed to airplanes with 3 or more engines where it gives a guideline on things to take into account for selecting an airport other than the nearest suitable one).

                                --- 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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