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  • #46
    And no, a stab jam is not a "common fault" on the 320 family.

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    • #47
      Originally posted by ATLcrew View Post
      Another alternative was that one was already MEL'd, remember?
      I suppose another possibility is that ELAC 2 failed on a previous flight due to something transient on the circuit. Since a faulty ELAC 2 is a no-go item even if ELAC 1 is working, they might have swapped them out and then MEL'd ELAC 2, now installed as ELAC 1 to dispatch the flight. Then ELAC 1, now installed as ELAC 2 met the same fate. At least then the circuit would be a common factor to both failures.

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      • #48
        Originally posted by ATLcrew View Post
        Another alternative was that one was already MEL'd, remember?
        I still consider that a coincidence. But as I said, it's certainly possible.

        Originally posted by ATLcrew View Post
        And no, a stab jam is not a "common fault" on the 320 family.
        'Common' as in both systems having it in common. A jammed stabilizer would create a common fault in both ELAC's.

        Comment


        • #49
          Stab jam (as a common fault) is looking a bit more plausible:

          A320, 2008:

          Flight control malfunction: the captain was hand flying the turn to base leg for a visual approach to ZZZ runway 7R when we received an amber flight control elac 2 pitch fault ECAM annunciation. Shortly after accomplishing the ECAM SOP for this fault; a second ECAM was displayed for an elac 1 fault followed immediately by a flight control stabilizer jam ECAM and flight control alternate law. All ECAM actions were accomplished with manual pitch trim found to be available. The flight control system degraded to direct law per the flight manual after landing gear extension and the landing was uneventful. Callback conversation with reporter revealed the following information: unfortunately; a power interruption occurred after the aircraft was parked at the gate which erased all the stored maintenance data. Tests revealed that there were disagreements between the ths position sensors but that they were within limits. Maintenance replaced both elac's to return the aircraft to service.

          Comment


          • #50
            Originally posted by Evan View Post
            What if I didn't say so? I said that losing both engines is as unlikely and hard to explain as losing both ELAC's. I never said it was as serious. Go back and read the post. It's pretty clear what I meant. Jesus, Gabriel, you were one of the few here that didn't twist my words around.
            Evan, if I was one of the few that didn't twist your words, there is a reason for that and I am still the same. I am not twisting your words. I quoted you immediately before my reply. Go and read your post yourself, at least the part that I quoted which trigged my reply.

            In any case, it is you who should use more caution when redacting the post. You asked, making ana analogy with the ELAC (and that's not a supposition, you expressly said that you were making the analogy) if it would be wise to dispatch an airplane with one engine. Come on!!!! I keep my position, that is a show-stopper. I cannot keep exchanging ideas with someone who has such idea.

            By the way, it is not correct that losing both engines is as unlikely and hard to explain as losing both ELAC's. Loosing bothe engines is much more likely and easy to explain. There are multitude of failure modes that can affect both engines at the same time: Fuel contamination (including ice crystals), birds, volcanic ashes, fuel exhaustion, shutting down the wrong engine. And we have examples (in most cases multiple examples) of all these things happening and leaving the plane without both (and up to 4) engines at the same time. We even have a case of a prop airplane where a blade separated and, in its flight through the fuselage, pulled all the throttle cables (and then cut them) effectively idling all 4 engines and leaving the crew without any control over the engines.

            Now to untangle that Gabrielesque post...

            No. Wrong.
            Maybe it is not pristine, but what is wrong?

            Once you have lost Normal Law, AoA protections and Alpha Floor...
            But I was explaining the direct law... in that part of the post. I was explaining how the Airbus don't meet the FAR requirement regarding longitudinal stability and what envelope protections they have in place and they used as alternate means of compliance.

            If you gain enough airspeed to exceed VMO/MMO the nose will come up. This is overrideable with increased stick force. This is true in Alternate law with reduced protections. This is true when you lose both ELAC's.

            If you lose enough airspeed to approach stall (5-10 kts above stall warning), the nose will lower. This is overrideable with increased stick force. This is true in Alternate law with reduced protections. This is true when you lose both ELAC's.
            I agree. That's why I later said "When the plane looses some systems it reverts to alternate law. In this condition, depending on the kind of failures, the envelope protections are significantly degraded or eliminated alltogether."

            Neither the certification authorities nor Airbus are the insane, irresponsible folks you make them out to be. That's what I'm getting at. But that certification was predicated on having certain systems, such as an ELAC, in working order.
            For the record, I didn't say that. I said that: "But the problem, for me unacceptable, is that the plane still lacks longitudinal stability because the basics of the normal law (stick-on-G / stick-on-pitch-rate) remain in place."

            It is not the same, ok? The authorities evidently don't agree with me (or at least didn't do it back then, now it would very hard for them to change their previous ruling on the case), but that don't make them "are the insane, irresponsible folks you make them out to be."

            We already discussed at length on the Airbus'controls design philosophy and you know that there are several things that I don't agree with, the main of which is the completely lack of visual/tactile feedback regarding "what the plane is doing now" with the controls (does the phrase sound familiar?). And yet, you know, I consider the Airbus planes very safe, have absolutely no problem or concerns when I climb into one, and object those who share my critiques but use these concepts to call the plane a death trap or similar.

            UAS is a different animal. Without airspeeds you can't have ANY speed protections...
            That is not true. Keeping a given pitch and thrust is something that the autoflight could possibly do (if it was enabled to do it) and you still have two perfectly working AoA vanes. Airbus chose not to use these resources.

            ... and that is far more immediately dangerous. That is why the procedures exist to maintain the airspeed envelope. That is why one of them has the distinction of being a memory item (except at Air France).
            That is not true. The investigation revealed a significant bunch of other UAS cases previous to AF where the memory items (or any part of the UAS procedure) were not followed either. Yet, they didn't pull up 1.5Gs, 7000fpm, and 2000ft and when the stall warning sounded, pulled up hard again ank kept "but I been pulling up all the time" all the time to the ground (or sea). Instead, all of them stick-and-ruddered and airmanshipped it out of it.

            And I want to make very clear that I am not promoting using this INSTEAD of the procedures (including the memory items). By all means, the procedures are there to be complied with, and that is almost always the correct, required and safest course of action. But not complying with the procedure doesn't explain by itself what the AF pilots did instead of complying with the procedure.

            That is why the first order of business when speeds return is to get it back on the automation. I have already agreed with you that UAS is a more dangerous situation on a airplane with automatic pitch trim and thus no out-of-trim 'feel' for speed changes. But UAS is one of those situations technology cannot yet contend with.
            Again, not true, unless you use "can't" as "technically perfectly possible and even easy but since this feature was not designed in the system, the system can't".

            It requires disciplined, well-trained pilots to fly safely through it.
            Yup, I agree with that, the same than for not losing airspeed and stalling during the final approach, of which we had 3 (THREE!!!) cases in the last years: Turkish, Asiana and the other one that splashed down and didn't smash into the seawall by inches.

            What baffles me is that you find the control laws philosophy alarming but not the fact that you can apparently lose both ELAC's in flight to a common fault. But that is because you have the control laws philosophy wrong...
            First of all, as you said, we still need to see why the plane was left without any ELAC. Maybe a common fault that was not taken into account, maybe independent faults (yes, that would be extremely unlikely remember it is a first in millions and millions of flights), or maybe one was MELed to begin with, as you said too.

            Second, I consider the lose of both ELAC of a seriousness comparable to the loss of autoflight. Comparable, not equal. It is a bit worse because you lose the ailerons (keeping spoilers for roll control) and, more important than that, because, with Airbus flight control philosophy and the change in control law and loss of protections, you leave the pilots flying a different plane, as you said yourself.

            I consider that fault serious but not very serious. If it is very serious it is because you don't have pilots (persons who master the art of flying airplanes, as opposed to persons who puch buttons) flying the plane. Then we have a bigger problem because those button pushers sometime find the way to crash the plane even with all the ELACs working.

            Did you know that, at least in some types, the whole autopilot is MELlable in certain conditions? (VMC). I was in a 737 flight where the pilots legally took off with no autopilot in working order. How I know? The captain told me that when I went to the cockpit and I asked him why was the FO hand flying.

            --- 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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            • #51
              Originally posted by 3WE View Post
              Lump 2: Many of us assume (incorrectly) that if they computers go down you get a plane that's very hard to fly.
              For the record, not me. You do to play extra careful attention to the airspeed and attitude though.

              Lump 3: ATL said (paraphrased) "all you had to do was land the thing, do some paperwork and then hit the coffee shop."

              More lump 3: And, in your continued attempt to get me to understand- I keep getting the lumped message that while you lose lots of fancy computer-stabilized flight inputs, you still get something that can be controlled.
              I totally agree with ATL and with your lump 3.

              I think we agree with Evan there, and maybe we don't want to stall or exceed the big $20 word "Envelope" the thing with the computers off (not that we want to stall it or exceed the "Envelope" with the computers on either)
              With the computers on... you can't even if you try hard!!! That's the point.

              Briefer bottom line lump: But it sounds to me from your posts and others, that dual ELACS failure is not a NEAR TOTAL AIR DISASTER!!!!!!
              Again, I fully agree with that. It was not my intention that my post sounded that way. I was the one confronting with Evan on that, and I just tried to explain Evan's point.

              --- 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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              • #52
                Originally posted by 3WE View Post
                Blah blah blah...

                Yeah, it's nice to have my 172 trimmed for healthy flight so that it "fights me" if I try to stall it, and there's the evil insidious Airbus that will pitch up, but not give me tactile feedback until the stall warning goes off. Shall I place links to ITS going over the top with trashing Airbus and Frenchmen?

                So, I'm back to one of my endless, repetitive rants:

                Select known, healthy power, attitude and speed settings and (do I have to say this- because it WAS implied) keep monitoring the airspeed and attitude and power (see footnote) to see that the airspeed and attitude stay at those healthy settings ...

                ...and then you will catch the plane when it starts going to the wrong attitude even though the plane doesn't give tactile feedback (and even though a Cessna would not go to the wrong attitude without tactile feedback)

                Footnote: To the best of my knowledge, most aircraft provide gauges (or flat panel readouts) to tell you about the air speed and the attitude and the power settings.
                I fully agree with all that, almost. The exception is "most aircraft provide gauges (or flat panel readouts) to tell you about the air speed". The abnormal alternate law, the one that will leave you with no slow speed / stall protection other than the stall warning (not even the longitudinal stability) happens precisely when you lose the airspeed.

                This doesn't mean that you have no option but stall the airplane. You still have the attitude indicator, the power setting instruments, and the memory item that tells you where to put both. You also have your airmanship to know that at 35000 ft you cannot pull 2G and climb 2000 ft at 7000fpm with a pitch angle of 15 degrees, and the stick-and-rudder skills to know how NOT to do that. Finally, if all that fails and you listen the stall warning with that cryptic ambiguous horn shouting STALL STALL STALL in plain English, you may (and many would say "should") think of perhaps lowering the nose a bit instead of "but I've been pulling up all the 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


                • #53
                  Originally posted by Evan View Post
                  The first officer requested an extended downwind and declared an emergency [note: I think we can assume that they considered this a serious situation].
                  No, we can't. We can't assume that they didn't either.

                  --- 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


                  • #54
                    Originally posted by Gabriel View Post
                    Maybe it is not pristine, but what is wrong?

                    But I was explaining the direct law... in that part of the post. I was explaining how the Airbus don't meet the FAR requirement regarding longitudinal stability and what envelope protections they have in place and they used as alternate means of compliance.
                    No you weren't. You were explaining in NORMAL law:
                    Originally posted by Gabriel
                    So, as you can see, the Airbuss don't comply with the FAR's longitudinal stabilty requirements, not in normal law at least.
                    And your description of the system behavior under Normal Law is flawed. You've left out key aspects that substitute for traditional speed stability. Then you were talking about ALTERNATE law:

                    Originally posted by Gabriel
                    When the plane looses some systems it reverts to alternate law. In this condition, depending on the kind of failures, the envelope protections are significantly degraded or eliminated alltogether. But the problem, for me unacceptable, is that the plane still lacks longitudinal stability because the basics of the normal law (stick-on-G / stick-on-pitch-rate) remain in place.
                    In most Alternate Law conditions, there is still the artificial speed stability. Only certain system failure scenarios (i.e. involving loss of ADR's, multiple hydraulic failures or certain slat failures) will result in a loss of all protections. Loss of reliable air data under UAS for instance... Therefore, in most Alternate Law scenarios I say the problem is serious, not unacceptable.

                    Originally posted by Gabriel
                    I agree. That's why I later said "When the plane looses some systems it reverts to alternate law. In this condition, depending on the kind of failures, the envelope protections are significantly degraded or eliminated alltogether."
                    That's more like it.

                    Back to my original point, I think, because the full spectrum of Normal Law protections was required to certify the aircraft without meeting the requirements as written in the FAR's, and scenario in which they are "significantly degraded or eliminated altogether" is a very serious incident. Again, I do not say...

                    Originally posted by 3WE
                    NEAR TOTAL AIR DISASTER!!!!!!
                    ... I do not say unacceptable. I say "very serious". In the case of total ELAC failure, serious enough to cause at least two recent incident crews to declare an emergency. Serious enough for every incident to make a diversion or return. Serious enough to look deeply into and prevent if possible in the future.

                    Originally posted by Gabriel
                    Second, I consider the lose of both ELAC of a seriousness comparable to the loss of autoflight. Comparable, not equal.
                    Are you really reading my posts? Loss of both ELAC's results in loss of autoflight. THAT'S WHY IT'S SERIOUS. Any loss of Normal Law protections that does not result in a loss of autoflight is only a dangerous condition (from a flight control standpoint) under manual flight. This is why UAS is only a transient danger. That is what reversion laws are intended for: to get the aircraft back on autoflight or on the ground asap. They are not intended for extended manual flight. But the loss of ELAC's means BOTH diminished envelope protections AND a loss of autoflight (itself a form of envelope protection). So, that IS a compound level of serious concern.

                    Originally posted by Gabriel
                    I consider that fault serious but not very serious.
                    Now you're just equivocating. It's either serious or it isn't. Serious means it has to be looked into with the intention of possibly altering system design or procedure or regulations to avoid a recurrence. That is essentially what I'm trying to say: this should never happen.

                    Now, all that said, I am learning that there are certain mechanical conditions that might result in both ELAC's tripping offline. That sort of thing might not be preventable from a systems design POV and can only be prevented by vigilant maintenance. Perhaps an AD stressing the need to periodically check the elements that might cause this condition are in order. If this is, in fact, the case.

                    It would be nice if a finding is eventually reported on this incident, but I'm afraid we will never hear anything more about it.

                    Comment


                    • #55
                      Originally posted by Gabriel View Post
                      Again, not true, unless you use "can't" as "technically perfectly possible and even easy but since this feature was not designed in the system, the system can't".
                      For the system to overcome this, at least all of the airspeed probes must be of a design that is not vulnerable to the same environment. Two must be working at all times. There are airspeed sensors, such as the ones on the SR71, that are not vulnerable to ice-ingestion, but they may not be applicable here either. Systems such as those based on AoA to extrapolate speed might be possible but AFAIK, there have been no solutions to the problem of providing reliable air data in certain icing environments to the ADR's, and without this the ADR's must disagree and initiate the cascade of system failures that depend on them.

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                      • #56
                        Originally posted by Gabriel View Post
                        Evan, if I was one of the few that didn't twist your words, there is a reason for that and I am still the same. I am not twisting your words. I quoted you immediately before my reply. Go and read your post yourself, at least the part that I quoted which trigged my reply.
                        Here's my post, verbatim:

                        Losing an engine, while also serious, is to be expected and can usually be easily explained. What about losing two engines, because that is the analogy if you are trying to make one. Did both engines fail by coincidence? Is it wise to dispatch with one engine on the MEL? Or is there a common design vulnerability that could cause both engines to fail?
                        The analogy is in what can be expected and explained, not in the level of seriousness. Obviously losing power is a magnitude of seriousness beyond degrading control law and losing autoflight. You don't have to twist my words to fuel the War on Evan here and make me look ridiculous. As always, I'm looking for a dialectic on this forum, not a polemic debate.

                        Comment


                        • #57
                          Originally posted by Evan View Post
                          No you weren't. You were explaining in NORMAL law:
                          Aw, right, I meant Normal.

                          And your description of the system behavior under Normal Law is flawed. You've left out key aspects that substitute for traditional speed stability.
                          Can you be more specific? Autothrust? (because I mentioned the low speed protections).

                          Then you were talking about ALTERNATE law:

                          In most Alternate Law conditions, there is still the artificial speed stability.
                          What speed stability? The remaining low speed portection? If it's that, I agree. But I would not call that a "speed stabilty". You can go all the way from 300 kts to 5 kts above the stall before this "speed stability"kicks is. I would not call a stick pusher "speed stability"either.

                          Only certain system failure scenarios (i.e. involving loss of ADR's, multiple hydraulic failures or certain slat failures) will result in a loss of all protections. Loss of reliable air data under UAS for instance...
                          I agree and that's what I said.

                          Therefore, in most Alternate Law scenarios I say the problem is serious, not unacceptable.
                          I agree, more or less. I consider this NOT a terribly serious issue, especially not in the standard alternate law. But I would have requested more from Airbus. "Ök guys, so you use this normal law in combination with all this range of excellent envelope protections in lieu of the lack of speed and AoA stability to ensure equal or better level of safety. Explain me again how this works when you basically keep the normal law that lacks speed and AoA stability, remove most of the protections (including the resistance to stall, even when you still have 2 goos AoA vanes), and in some cases remove even ALL the protections, change the name to Alternate law, and you are still offering an equal or better safety than the required stability? (talking only of the longitudinal motion).

                          I've already said that I consider the Airbus planes very safe and fly on them with no concerns (I fear much more the airlines and the pilots than the plane).

                          Back to my original point, I think, because the full spectrum of Normal Law protections was required to certify the aircraft without meeting the requirements as written in the FAR's, and scenario in which they are "significantly degraded or eliminated altogether" is a very serious incident. Again, I do not say unacceptable. I say "very serious".
                          Well. I don't agree but respect your opinion. Again, my "unacceptable" is not of the "these things are killing machines" type, but of the type "I would have requested more from Airbus because it looks to me that it neither meets neither the FAR criteria (objective fact) nor reaches and equal level of safety (subjective opinion). Again, ESPECIALLY in abnormal alternate law, which unfortunately is not an extremely rare occurrence because UAS is not an extremely rare occurrence.

                          In the case of total ELAC failure, serious enough to cause at least two recent incident crews to declare an emergency. Serious enough for every incident to make a diversion or return. Serious enough to look deeply into and prevent if possible in the future.
                          Pilots declare emergency every time they have an engine failure (much more common that double ELAC failure, you have a bunch of cases every week), for low fuel (ditto, and "low fuel" doesn't mean that the plane actually reaches a critical level of fuel, just that the current clearance may have the plane landing with less than the final reserves), medical emergencies, or just unacceptable clearances. That's why I said that I didn't know if they considered it very serious. They were in the approach and needed to extend the downwind to run the checklist. And the clearance was for them to land, so they needed to deviate from that. Perhaps they decided that, instead of negotiating a clearance with the ATC it was better, to lower their workload and receive priority handling, to just declare emergency, state their intentions, and let ATC handle the rest. Or perhaps they considered the situation "serious enough".

                          If "serious enough" is the trigger to revisit the situation and analyze if an improvement is warranted, then by all means I support your "serious enough" diagnostics.

                          Are you really reading my posts? Loss of both ELAC's results in loss of autoflight. THAT'S WHY IT'S SERIOUS.
                          Yes I do. And are you reading mine? I don't consider loss of autoflight a very serious condition. Planes can be released without autopilot. I flew in (at least) one of them. Now, if you tell me that in alternate law you need autoflight for the plane to be safe, then I consider THAT DESIGN PHILOSOPHY an unacceptable condition (unacceptable in the same terms stated above, ok?).

                          That is what reversion laws are intended for: to get the aircraft back on autoflight or on the ground asap. They are not intended for extended manual flight.

                          But the loss of ELAC's means BOTH diminished envelope protections AND a loss of autoflight (itself a form of envelope protection).
                          So the "on the ground ASAP" part applies. I don't see a contrast between both paragraphs, as you "BUT' at the beginning of the second one seems to imply.

                          And autoflight is NOT itself a form of envelope protection. Figure this:
                          UAS, AP/AT disconnects, pilots run the memory items and the rest of the procedure, UAS remains for some time and they decide to descend looking for better conditions (warmer air, denser air...). So they idle the engines and follow the required pitch and VS, UAS disappears, they remain in alternate law but they regain autoflight. They engage autoflight and tell autoflight to level off. They forgot the throttle levers in idle....

                          Now, if I understand the system correctly, nothing (except human airmanship) will prevent the autopilot from keep pitching up while the plane losses hundreds of knots, and nothing will add thrust either. Not, until the LOW SPEED PROTECTION kicks in and lowers the nose. So it was the LOW SPEED PROTECTION that is independent of auto/human flight, not the autoflight, which saves the day.


                          Now you're just equivocating. It's either serious or it isn't.
                          I have an old CRT color TV that you can use to replace your B&W one.

                          Yes, I read your definition of "serious" that came after that. Based on THAT definition, let's call it serious.

                          --- 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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                          • #58
                            Originally posted by Evan View Post
                            For the system to overcome this, at least all of the airspeed probes must be of a design that is not vulnerable to the same environment. Two must be working at all times.
                            Ok, yes, the UAS cannot be avoided with the current design of the speed sensors (pitots). But that's not what I meant, and I aknowledge that I was not clear enough.

                            GIVEN THE UAS, Airbus could have treated the situation differently.
                            - The ADRs don't need to disagree at full. They can just agree that they disagree on the speed, and consider this just a speed disagreement and on an ADR disgreement.
                            - The autoflight and autothrust don't need to give up immediately. At the very least, they can keep the current pitch and thrust (thurst in fact will be kept by the thrust lock feature) while they give the pilots a clear indication of what is happening (a Unerliable Airspeed, take manual control, disconnect AP/AT, keep pitch 5, move throttle off and back to CLB" would be very nice (better than the miryads of ECAM fail messages from which the pilots have to deduce that they have an unreliable airspeed condition) and easy, and the autoflight can wait until pilot action to disangage. A few seconds of that will not hurt, and in any event whatever the current pitch and thrust cannot be worse.
                            - It would be very easy for the AP/AT to apply the memory items by themselves.
                            - You could keep the degraded slow speed protection of the standard alternate law using the AoA vanes (if they agree). Yes, stall AoA depends on Match, and Match depends on speed, but you can select a reasonable fixed AoA trigger value that will pitch down slightly faster than required at low Match, and still prevent a stall at high Match.

                            --- 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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                            • #59
                              Originally posted by Evan View Post
                              Here's my post, verbatim:



                              The analogy is in what can be expected and explained, not in the level of seriousness. Obviously losing power is a magnitude of seriousness beyond degrading control law and losing autoflight. You don't have to twist my words to fuel the War on Evan here and make me look ridiculous. As always, I'm looking for a dialectic on this forum, not a polemic debate.
                              Evan, in the the post before that one you said: "5) Notice that in the scenario where both ELAC's have failed and most of the envelope protections are lost, the aircraft no longer meets the alternate criteria either. Hence, from an airworthiness certification standpoint, it is now unsafe to operate as a transport category aircraft and must be landed ASAP. "

                              I compared that with losing one engine, which is a far more usual situation than losing both ELAC, both of which require land ASAP, and that, in my opinion, losing one engine was more serious than losing both ELAC (meaning that, if both situations happened with equal frequency, I would expect more accidents for the former).

                              Then you came saying that losing two engines was a better analogy (if you lose both engines chances are that you will land even sooner than ASAP) and asked if it was wise to dispatch a plane with one engine.

                              But let's put an ending to this, if only for clemency. Evidently you meant something else than what you meant and whether it was because your message was not clear or because I was misinterpreted it is not important.

                              You know that you and I disagree a lot of times. You know that I respect you, and that (almost) always I reply (to you and everyone) in a constructive way. I simply was startled and didn't know how to react to or answer the "Would you dispatch an airplane with one engine MELed" question. That is beyond my powers. For sure, you can't dispatch my Tomahawk with one engine MELed, for reasons far beyond the fact that the regs don't allow 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


                              • #60
                                Originally posted by Gabriel View Post
                                But let's put an ending to this, if only for clemency. Evidently you meant something else than what you meant and whether it was because your message was not clear or because I was misinterpreted it is not important.
                                OK, that's confusing, I admit, and you misinterpreted it. What I meant by 'dispatching with one engine' was based on the hypothesis that this could have been a dispatch with one ELAC and was referring to the low probability of losing the other one. I don't like the idea of dispatching without redundancy for a key flight control system and without redundancy for autoflight based on the unlikelihood of a second failure. The engine analogy was referring to the low probabilty of a second failure.

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