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Available Approaches and Vertical Guidance


Saffa_Jake

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Hi,

 

First of all thanks for the amazing software. I have a question about the available approaches and vertical guidance. First my setup:

Xplane 11 1.41

Navigraph FMS data for all add-ons including EFB v2 (AIRAC 2004)

 

Approaches

I am practicing flying an approach into KASE and I noticed the RNAV-F is not available to select as an arrival in EFB. I read on the forums that this was due to Navigraph and other sources not including circling approaches. Is this still a thing as all my add-ons that rely on Navigraph have this as a selectable approach?

 

Vertical Guidance

When flying the RNAV 15Z into KASE I noticed the vertical guidance is aiming for an altitude of  10000 and ignoring all the published restrictions, see below. I tried following the VG down to the runway but it was ignoring the restrictions. Am I doing something wrong or is this intended? I did read on the forums that the vertical guidance is calculated down to the FAF based on the profile settings and ignoring all other restrictions, is this correct and applicable in the below situation?

image.thumb.png.c928e4f468319665c53abb12fba670c5.png

 

Thanks! 

 

Jacques

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Hi Jaques,

 

1) Yes, unfortunately the circling approaches are still not part of the EFB database provided by Navigraph.

 

2) The vertical guidance (VG) calculates the descent path backwards, starting at the runway threshold, taking the descent angle from the currently loaded aircraft profile and considers all restrictions along the path up to your cruise altitude. On the VG panel on the right side of the map only the points will be indicated where the descent angle changes, or where a restriction of type "AT" is set. In other words, as long as the calculated path is above of the "AT or above" restrictions and no descent angle changes, no point will be indicated.

 

On your screenshot the vertical guidance (VG) indicates "*10K" as the next point where the descent angle changes. That means that you most probably are on a descent path above all the "AT or above" restrictions and the next change is at this virtual point (aka "magenta dot") where you will pass the altitude of 10'000 feet and therefore the second angle from the aircraft profile becomes active. The thing that makes me puzzled a bit is that the magenta dot is not on the lateral path and unfortunately I can't see the side panel of EFB, so I don't see whether the "active waypoint" is properly set.

 

EDIT: I just have created the same FPL on my system and I can confirm that the magenta dot is off of the lateral path so it obviously has nothing to do with what you have configured.

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Thanks for the feedback and checking into this. The explanation makes sense, however, I completed the approach and none of the restrictions were adhered to up until the magenta dot and I was not on a descent path  that put me above those restrictions. Apologies for cutting off the sidebar, I do always make sure that I am tracking to the correct waypoint but will make sure to include it in future screenshots.

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  • 8 months later...

So a question to add on to this topic, So to use the APP and SID into KLAL as an example,  When flying the BLOND5 and the ILS RWY 9, the VG is set to the first waypoint from the runway which is FLYEN "AT" 1700.  The BLOND5 has an "AT" 10000 at waypoint BLOND.  I understand that if the restrictions from TOD to, say FLYEN are all "AT or ABOVE" said altitude that your glide is set so you are at or above as you descent to FLYEN 1700, but if the SID has an "AT" 10000 at BLOND shouldn't the VG use that as a VG start so your TOD is not passed BLOND?   And is there a way to add it to your Flight plan so that it set the VG to THAT point and not FLYEN?  I love the VG, just what to better understand ways to utilize it.

 

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Vertical guidance is calculated using descent angles from the A/C profile. Usually this is 3.0° below 10'000ft and 3.5° above 10'000ft. It always starts at the FAF and goes up until reaching TOD. All altitude restrictions AT, AT OR ABOVE, AT OR BELOW and BETWEEN will be considered. If you fly along the vertical path you will be safe concerning the published altitude restrictions of the procedures. When creating your FPL don't forget to integrate the procedure waypoints by pressing "Set FPL" on the procedure selection dialog.

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4 hours ago, aivlasoft said:

Vertical guidance is calculated using descent angles from the A/C profile. Usually this is 3.0° below 10'000ft and 3.5° above 10'000ft. It always starts at the FAF and goes up until reaching TOD. All altitude restrictions AT, AT OR ABOVE, AT OR BELOW and BETWEEN will be considered. If you fly along the vertical path you will be safe concerning the published altitude restrictions of the procedures. When creating your FPL don't forget to integrate the procedure waypoints by pressing "Set FPL" on the procedure selection dialog.

I do integrate the procedures into the FLP but I would like to see the VG show the TOD for the say first "AT" 10000 waypoint.  So for example if I could manually put in the 10000 "AT" BLOND then that would be the point that the VG starts at and not the FAF.  

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I just tried to explain how the calculation will be done. The calculation is done upwards, therefore the FAF is the first point where the calculation starts. When you fly the route, then obviously the descent profile starts at TOD (top of descent) which always is at cruise level. The VG-system is not designed to allow manual and therefore individual input.

 

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