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cmdurney

VNAV...FMC U10.8 or FMC U10.7 software?

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Hi PMDG Team,Just wondering what FMC software is coded in 737NGX. I hope its FMC U10.8 so we can arm VNAV on Takeoff!!!REF: Boeing FCTM 3.33/3.34"With FMCU10.8 and later, VNAV is normally armed for takoff and engages at 400ft AGL. The use of VNAV for takeoff, flap retraction and climb out is the preferred method of managing the AFDS for takeoff. This provides the VNAV profile and acceleration schedule compatible with the planned departure.On airplanes with FMC U10.7 and earlier, at thrust reduction altitude, select or verify that climb thrust is set. At acceleration height, set flaps up maneuver speed and retract flaps on Flap retraction Schedule."Cheers Chris

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It uses FMC U10.8Check out this picture of the VC. You can see the OP PROGRAM on the CDU.http://forum.avsim.net/topic/335678-this-is-what-an-ng-really-looks-like/page__view__findpost__p__1981319

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Not only this but we have soft speed constraints - first addon ever to model that.

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Not only this but we have soft speed constraints - first addon ever to model that.
If you don't mind my asking, what are soft speed constraints?

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You can enter at or above or at or below for speeds as well as altitudes. The math behind how this all works while calculating the descent path is *extremely* complex and it's one of the reasons development has taken longer than we'd have liked.

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You can enter at or above or at or below for speeds as well as altitudes. The math behind how this all works while calculating the descent path is *extremely* complex and it's one of the reasons development has taken longer than we'd have liked.
I like posts like this because they remind us that we're waiting for something truly amazing.

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This is truly going to be worth the wait. I can't even imagine all the time and research it takes to code these systems (and making sure such code doesn't have a negative impact on other systems code and/or computer performance).I'm as anxious as the next guy for release, but they have to take the time to get it right, and since they are adding things never seen before in flight sim, I am grateful that they are not in a rush to get this out the door like most other developers.All this attention to the smallest details, has made me scrutinize my other addons and see things that are not quite right that I have never paid much attention to before. It will be nice to see VNAV behavior that performs as intended by Boeing itself, and not use FSX limitations as an excuse.I must ask though, as much as I'm excited that 10.8 is being modeled, is there a chance that 10.7 or earlier can be an airliner option in the NGX? I have that "other" NG and it models 10.7, and I've actually become quite accustomed to the difference in takeoff profile vs. 10.8. In 10.7, at the acceleration height the pilot commands flaps up maneuver speed, retracts flaps as scheduled, and only enables VNAV once flaps are up. It would be the ultimate in realism to choose which FMC software to use, as I'm sure some NG carriers still use 10.7. No biggie if it's 10.8 only, but after hearing about the multitude of customization in the NGX, I wanted to ask. One last question, I also hope there is an indication on the N1 gauge that shows where our hardware throttle is positioned, to help us when we disconnect the autothrottle during finals, as well when the autopilot retards throttles and goes into ARM mode during descent or LVL CHG mode. I hate how there can be a spike in thrust at these moments because we do not have motorized throttles that match the simulation position, and even though it is not 100% realistic because the real plane doesn't have it, a concession should be made because this is flight simulator. I believe it was mentioned this may be an option, but like I wanted to confirm if this is indeed something we can expect.Thanks!

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A.J.Both options are already there. We don't have it switching between 10.7 and 10.8 per se in terms of all the differences that exist, but that VNAV arming on the ground before takeoff option is there. You're also going to see the first ever accurately modeled fail-operational vs. fail-passive autoland capability too, which is another option. We've also got the IAN/GLS approach stuff that's in 10.8 too - if you have the Reality XP WAAS GPS unit, think of that that sort of LPV approach idea but for an airliner. You get "FAC" and "GP" as your active roll and pitch modes on the FMA during this type of approach and the virtual "localizer" and "glideslope" are completely generated by our FMC.Were you the original person who asked about the physical throttle indication? We implemented that specifically because of a forum request - it was a great idea and we came up with a really neat way to do it. I use it all the time myself.

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Thanks for the information Ryan. I own the PMDG manuals, and I'm excited to know that stuff I read in there that I would have thought was not possible in FSX is in fact going to be in the NGX. I am at a loss for words really, I have no doubt that if a procedure or system is in those manuals, and FSX's limitations can allow you to implement it with or without a workaround, chances are the NGX will have it modeled. I can't imagine flying IAN approaches yet, but I am happy to know that when that day comes I will study the manual accordingly, and I'm sure some of the NG diehards (both simulation and real life pilots) are drooling with that news!Regarding the throttle n1 question, I wasn't the original poster, but I know I had read it some few months back. I guess we all weren't sure if this feature is going to be included, and I'm very excited to hear it is! You fellas really have covered everything, it's amazing the level of thought that is being put into this project and I for one understand the delays......months of delays means YEARS of enjoyment.

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Good to know all that funky IAN stuff is in there.Al

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How does PMDG know how to do this? Is this how extensive your research was? Amazing....

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According to Boeing "737 IB 2011-01", released at January 6, 2011, there is an anomaly in FMC Update 10.7, 10.8 and 10.8A which causes windshear guidance to be incorrect if VNAV is armed on the ground. VNAV remains armed until 400ft AFE, even if TO/GA is pressed in accordance with the Windshear Escape Maneuver. Consequently, at 400ft VNAV engages and windshear guidance is lost. Another press of TO/GA has to be made to regain the correct windshear guidance. Of course, I don't know if it is possible to simulate windshear in FSX, but I wonder if PMDG also coded this into the FMCs.Okay, I admit, heard it today during T/O roll so that made me wonder what PMDG has done with it...Thinking.gif

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The PWS system operates on Doppler radar returns of tiny amounts of moisture in the air, so unfortunately no for the same reason we can't do the main wx radar... FS just doesn't have that level of modelling in it's atmospheric and weather engine.

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Hi Everybody, I´m not a professional, but I know that the 737NG (depending on the Version) is not able to perform a CATIIIB (ROLLOUT and hold center line via Autopilot) approch.Dose this ability depends on the FMC Version? Has the PMDG 737NG CATIIIB abilities?Kind RegardsSteffen Lutz

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I believe with the old MCP style, it does not have the CATIIIb, but with the nex Honywell MCP, it did. But I stand to be corrected.

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Hi Everybody, I´m not a professional, but I know that the 737NG (depending on the Version) is not able to perform a CATIIIB (ROLLOUT and hold center line via Autopilot) approch.Dose this ability depends on the FMC Version? Has the PMDG 737NG CATIIIB abilities?Kind RegardsSteffen Lutz
I think it's been said just recently that there would be a selectable fail-passive/fail-operational autoland system so yes, it's quite safe to say it would be CATIIIB capable, including align and rollout.
I believe with the old MCP style, it does not have the CATIIIb, but with the nex Honywell MCP, it did. But I stand to be corrected.
Well I believe you are correct, sort of, as I have posed pretty much the same question some time ago. Guess I didn't get a definite answer but I'd have to dig out that thread again, so thanks for the unintended reminder. OTOH I just remember an NG driver once told me it might have to do with 2- vs. 3-axes A/P. Now it could be the old one is only 2-axes (+Y/D) while the Collins is 3-axes, hence capable of align and rollout. He wasn't really sure though, I can just say on that particular flight where I asked him he was flying the old one, and that was certainly IIIA only.sig.gif

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Hi Everybody, I´m not a professional, but I know that the 737NG (depending on the Version) is not able to perform a CATIIIB (ROLLOUT and hold center line via Autopilot) approch.Dose this ability depends on the FMC Version? Has the PMDG 737NG CATIIIB abilities?Kind RegardsSteffen Lutz
I believe with the old MCP style, it does not have the CATIIIb, but with the nex Honywell MCP, it did. But I stand to be corrected.
I think it's been said just recently that there would be a selectable fail-passive/fail-operational autoland system so yes, it's quite safe to say it would be CATIIIB capable, including align and rollout.Well I believe you are correct, sort of, as I have posed pretty much the same question some time ago. Guess I didn't get a definite answer but I'd have to dig out that thread again, so thanks for the unintended reminder. OTOH I just remember an NG driver once told me it might have to do with 2- vs. 3-axes A/P. Now it could be the old one is only 2-axes (+Y/D) while the Collins is 3-axes, hence capable of align and rollout. He wasn't really sure though, I can just say on that particular flight where I asked him he was flying the old one, and that was certainly IIIA only.
This is all fully and realistically modeled in the NGX:For the Fail Operational Autoland option to work, you also need the the Collins MCP and the ISFD options selected. (these will be automatically turned on if you enable the option.) Those two things alone do not give an NG fail operational capability though, it's a software and mechanical modification as well, so it remains a separate option on its own. You can have a Collins+ISFD aircraft without fail operational autoland - in fact that's exactly the configuration in place at a couple of our testers' airlines.The Fail Operational Autoland option essentially enables the more modern autoland system that's seen in the 747-400, 757/767 and 777. You get LAND2/3 annunciations, FLARE guidance from the FD and rudder control that includes ROLLOUT guidance and automatic crosswind de-crabbing. You also get a new MFD button below the normal ENG and SYS buttons that says "C/R" on it - this is the cancel/recall button for the autoland mode messages that can appear on the upper DU in the event of reversions or failures during the approach.The third inertial source for the system is provided by the ISFD's internal AHRS combined with the two normal IRUs. The Collins MCP actually has a hidden third autopilot channel that is not pilot controllable - this sends commands to a rudder servo that is part of the option/modification.When in the older Fail Passive Autoland mode, you will not get LAND2/3 annunciations, FD guidance in the flare or any rudder control while doing the autoland. As rollout guidance is part of the spec for Cat IIIB, fail passive systems are limited to Cat IIIA. At airlines like SWA, they actually chose to outfit the HGS system and their Cat III approaches are handflown by the captain. You can do it any way you'd like with the NGX!

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This is all fully and realistically modeled in the NGX:For the Fail Operational Autoland option to work, you also need the the Collins MCP and the ISFD options selected. (these will be automatically turned on if you enable the option.) Those two things alone do not give an NG fail operational capability though, it's a software and mechanical modification as well, so it remains a separate option on its own. You can have a Collins+ISFD aircraft without fail operational autoland - in fact that's exactly the configuration in place at a couple of our testers' airlines.The Fail Operational Autoland option essentially enables the more modern autoland system that's seen in the 747-400, 757/767 and 777. You get LAND2/3 annunciations, FLARE guidance from the FD and rudder control that includes ROLLOUT guidance and automatic crosswind de-crabbing. You also get a new MFD button below the normal ENG and SYS buttons that says "C/R" on it - this is the cancel/recall button for the autoland mode messages that can appear on the upper DU in the event of reversions or failures during the approach.The third inertial source for the system is provided by the ISFD's internal AHRS combined with the two normal IRUs. The Collins MCP actually has a hidden third autopilot channel that is not pilot controllable - this sends commands to a rudder servo that is part of the option/modification.When in the older Fail Passive Autoland mode, you will not get LAND2/3 annunciations, FD guidance in the flare or any rudder control while doing the autoland. As rollout guidance is part of the spec for Cat IIIB, fail passive systems are limited to Cat IIIA. At airlines like SWA, they actually chose to outfit the HGS system and their Cat III approaches are handflown by the captain. You can do it any way you'd like with the NGX!
That's just awesome. I don't understand half of it but it's still awesome.

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Snip...
That's awesome.Is the "C/R" button something that is on all NG's with the fail operational autoland option, or is that an option for the option so to speak? I'm wondering if I can go look at cockpit pictures to see which airlines have the fail operational autoland option.

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The C/R button is required for it. There's relatively few that have it right, I believe it's a fairly expensive option - only airlines that do a lot of flying into airports where visibility is commonly down to Cat IIIB minimums would get it.Look at Jetairfly's 700's on a.net - they have some with the option.

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And the one pic on a.net of Ethiopian's 737-800 shows the C/R button.

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This thread has some very cool information. Thanks Ryan for sharing this. Very impressive this stuff is in the NGX package.

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The Fail Operational Autoland option essentially enables the more modern autoland system that's seen in the 747-400, 757/767 and 777. You get LAND2/3 annunciations, [...]The third inertial source for the system is provided by the ISFD's internal AHRS combined with the two normal IRUs. The Collins MCP actually has a hidden third autopilot channel that is not pilot controllable - this sends commands to a rudder servo that is part of the option/modification.
Well, I was once taught you'd need three A/Ps for fail-operational capabilities (as that's part of the concept, sort of), so that was why I always wondered how that works on the apparently 2-A/P equipped Airbuses and NGs worked. So the LAND "3" obviously indication treats that third channel as the third A/P. I didn't know there was a hidden channel, but is explains a lot (anyone a clue if the 'buses use a similar setup? I believe there is no 'bus >A300 that is not fail-operation but I stand to be corrected). Still, you say it controls the rudder - but just the rudder? What if, say, A/P A fails - then B plus that third channel remain, and for fail-operational they would need to be able complete the landing. Who would crosschecK A/P B in that case? Don't A and B usually check each other?
Is the "C/R" button something that is on all NG's with the fail operational autoland option, or is that an option for the option so to speak? I'm wondering if I can go look at cockpit pictures to see which airlines have the fail operational autoland option.
Very interesting. That made me actually check a few more pics on a.net because I had thought of a few Collins MCP equipped ones they were all fail-operational then (cause I didn't know about the C/R requirement), and now to find out they are lacking that very button, so no IIIB for them I guess. Thanks for the heads-up.sig.gif

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Thanks for the reply, Ryan. I didn't consider that it's an expensive option that not everyone would buy, but that makes perfect sense now that you've said it. I looked at the Jetairfly pics and the Ethiopian picture Alex point out and it looks strange to see the button, simply because I'm so used to only seeing two.That did lead to another question, is there ever a fourth button? Not necessarily for the FOA option, but for anything else.

Very interesting. That made me actually check a few more pics on a.net because I had thought of a few Collins MCP equipped ones they were all fail-operational then (cause I didn't know about the C/R requirement), and now to find out they are lacking that very button, so no IIIB for them I guess. Thanks for the heads-up.
I'm glad Ryan responded, otherwise I would have been sitting here and looking through a ton of pictures trying to find it. LOL.gif

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