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Greetings, with the new -8. I've tried 2 Autolands, both with LAND 3 active. Right before the threshold,  the plane veers off course. Both times this happened with no wind.   The annunciator has FAC displayed, then when the veering occurs a line goes through the FAC letters on the PFD. AM I missing a setting or is this normal?

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If your FMA shows "FAC" you are on an IAN-approach (integrated approach navigation). So you have to land manually because this kind of landing mode is non precition.

But with your information given, i can't tell you why exactly the flight mode has changed. 

But there is a feature to correct the LOC Course to the SIM:

quote:

"CORRECT LOC CRS TO P3D: When it comes to navigation data, P3D has an inherent weakness in that data related to ILS/LOC stations is hard coded into the simulator and is not updated to keep it current with the normal magnetic shift. The end result is that the localizer final approach course in the P3D world will sometimes vary from the real world. Since many users are also using real-world navigation charts, this can create some confusion and can also create problems if the LOC course is not correctly set to match the P3D hard-coded information. (The airplane cannot fly the localizer properly if the CRS on the CDU NAV RAD page is set incorrectly) To compensate for this, we recommend setting this option to ON, and we will read the appropriate P3D localizer course and adjust the setting for you, thus saving you time and frustration."

(Page 98 PDF Introduction manual 744-748)

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48 minutes ago, PGBosak said:

If your FMA shows "FAC" you are on an IAN-approach (integrated approach navigation). So you have to land manually because this kind of landing mode is non precition.

But with your information given, i can't tell you why exactly the flight mode has changed. 

But there is a feature to correct the LOC Course to the SIM:

quote:

"CORRECT LOC CRS TO P3D: When it comes to navigation data, P3D has an inherent weakness in that data related to ILS/LOC stations is hard coded into the simulator and is not updated to keep it current with the normal magnetic shift. The end result is that the localizer final approach course in the P3D world will sometimes vary from the real world. Since many users are also using real-world navigation charts, this can create some confusion and can also create problems if the LOC course is not correctly set to match the P3D hard-coded information. (The airplane cannot fly the localizer properly if the CRS on the CDU NAV RAD page is set incorrectly) To compensate for this, we recommend setting this option to ON, and we will read the appropriate P3D localizer course and adjust the setting for you, thus saving you time and frustration."

(Page 98 PDF Introduction manual 744-748)

HI, ok that makes sense regarding the FAC.  I do have the LOC course to P3D on. Is this FAC a feature of the -8? I was landing in KPHX-ILS-Rwy 26 both times, in the -400 Auotland worked perfectly.

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1 hour ago, rfelger said:

HI, ok that makes sense regarding the FAC.  I do have the LOC course to P3D on. Is this FAC a feature of the -8? I was landing in KPHX-ILS-Rwy 26 both times, in the -400 Auotland worked perfectly.

To be clear, you only get autoland if you get the LAND3 notification, which you wouldn't have gotten with FAC/GP. In reality, what happened, is the plane was just flown into the ground by the automation. You can do the same using HDG SEL and V/S too, and it's no more of an autoland than what you saw with FAC/GP.

You got this because you tried to arm APP without first confirming the LOC and/or GS signals were being received. Because of this, the plane assumed you weren't going to get the latter (or didn't want to use them), and just entered IAN mode and plotted it all out on its own.

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Kyle, I always select LOC until its captured. So are you saying that I shouldn't arm approach immediately after the LOC is captured, & I should wait till the GS signal is displayed? I cant remember if the GS signal was on the PFD when I selected APP which I normally select right after the LOC is captured.

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5 minutes ago, rfelger said:

Kyle, I always select LOC until its captured. So are you saying that I shouldn't arm approach immediately after the LOC is captured, & I should wait till the GS signal is displayed? I cant remember if the GS signal was on the PFD when I selected APP which I normally select right after the LOC is captured.

To be honest, I think we're in need of a screenshot to see what we're up against.

Who's bringing you in so far out that you don't have vertical and lateral guidance on the ILS?

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Quote

CORRECT LOC CRS TO P3D: When it comes to navigation data, P3D has an inherent weakness in that data related to ILS/LOC stations is hard coded into the simulator and is not updated to keep it current with the normal magnetic shift. The end result is that the localizer final approach course in the P3D world will sometimes vary from the real world.

I guess that this is why I sometimes seem to be offset slightly from the runway heading when I am making a LOC/DME approach?

Edited by Christopher Low

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10 minutes ago, Christopher Low said:

I guess that this is why I sometimes seem to be offset slightly from the runway heading when I am making a LOC/DME approach?

Could be - depends on what you're referring to by "offset." Naturally, wind will cause you to be pointed in a different direction than your ground track, but you'd track down the dashed line on the ND.

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Last night I was approaching Perth YPPH with the -8. wanted to do the ILS 19 or something... I ended in FAC/GP. Why? Because the word not allowed default scenery of Perth has no ILS at all in my sim... -.- no idea why, but it‘s the same in Cape Town, in Salt Lake City, many big airports miss the ILS. -.- 

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1 hour ago, scandinavian13 said:

To be honest, I think we're in need of a screenshot to see what we're up against.

Who's bringing you in so far out that you don't have vertical and lateral guidance on the ILS?

Ok ill do that approach again this evening. I think you may be on to something with the GS but i don't recall this happening with the 400.. I had lateral LOC guidance, then when it captured, i armed APP right after, & i don't recall if the GS was active. I was using the default ATC in P3D for test flights.

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I've taken my lessons learned from the B737 with IAN and applied them to the B748, basically both are very similar in this regard.  In spite of trying to be careful about having both LOC and GS deviation indicators present before arming APP, I still managed to get myself landing PANC ILS07R the other day with the FMA indicating LOC/GP.... GP instead of GS.  It was VMC so it wasn't a problem, and one can reset the FD to clear the condition and try again but I always try to make sure I'm receiving the ILS before hitting APP.

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4 minutes ago, downscc said:

I've taken my lessons learned from the B737 with IAN and applied them to the B748, basically both are very similar in this regard.  In spite of trying to be careful about having both LOC and GS deviation indicators present before arming APP, I still managed to get myself landing PANC ILS07R the other day with the FMA indicating LOC/GP.... GP instead of GS.  It was VMC so it wasn't a problem, and one can reset the FD to clear the condition and try again but I always try to make sure I'm receiving the ILS before hitting APP.

Hey Dan, thanks for the info. So I'm guessing maybe there is something inherent to the -8 that it defaults to the LOC/GP instead of flying the ILS approach selected in the FMC?

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11 minutes ago, rfelger said:

So I'm guessing maybe there is something inherent to the -8 that it defaults to the LOC/GP instead of flying the ILS approach selected in the FMC?

Not necessarily. As I mentioned earlier, if you ask it to do something for which it doesn't have data, it'll go to IAN to make up its own. The 400 didn't have this mode, so it would just arm the mode and wait until the data became available. In this case, you're doing the same thing before the data is available, and the 748 is just assuming you want to just run with whatever it can give you.

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9 minutes ago, rfelger said:

Hey Dan, thanks for the info. So I'm guessing maybe there is something inherent to the -8 that it defaults to the LOC/GP instead of flying the ILS approach selected in the FMC?

If the aircraft is not receiving a GS signal then it pretty much has to default to GP.  Right?  The FSX/ESP/P3D platform has a very rudimentary simulation of an ILS and when we add IAN to the equation then the simple simulation model reveals its weaknesses.  For purposes of simulation, I recommend waiting until you show indications of receiving the signals before arming APP.  Note that the simulation has a much shorter range for GS than for the LOC, and neither are representative of the real world.

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