VNAV Advisory Descend
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VNAV Advisory Descend
Hi,
is it possible to have the direct descend angle/FPM indication while descending manually using VS?
As soon as I press VNAV and switch to VS mode the indication "DIRECT 3.0° 1100v" disappears. In the FMS I see option VNAV ADVISORY, however enabling/disabling doesn't change anything.
Cheers,
Stefan
is it possible to have the direct descend angle/FPM indication while descending manually using VS?
As soon as I press VNAV and switch to VS mode the indication "DIRECT 3.0° 1100v" disappears. In the FMS I see option VNAV ADVISORY, however enabling/disabling doesn't change anything.
Cheers,
Stefan
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Re: VNAV Advisory Descend
Hi,
in version 1.1.27 it appears that the magenta direct descend angle/FPM indication in VPATH has completely disappeared.
What happened to it?
Regards,
Stefan
in version 1.1.27 it appears that the magenta direct descend angle/FPM indication in VPATH has completely disappeared.
What happened to it?
Regards,
Stefan
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Re: VNAV Advisory Descend
Hi,
Which version? .27 or .28?
In .27 it works fine. Can you reproduce and post an image? Or give more details?
Thanks!
Tomas
Which version? .27 or .28?
In .27 it works fine. Can you reproduce and post an image? Or give more details?
Thanks!
Tomas
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- Posts: 57
- Joined: Sun Dec 22, 2019 1:27 pm
Re: VNAV Advisory Descend
Hi Tomas,
the issue is reproducible upon two flights in 1.1.27 and one flight in 1.1.28. Since I re-started flying (stopped in December) I did not observe any additional VNAV information in magenta color anymore. The following screenshot shows a regular descend in VPATH:
Any ideas?
Cheers,
Stefan
the issue is reproducible upon two flights in 1.1.27 and one flight in 1.1.28. Since I re-started flying (stopped in December) I did not observe any additional VNAV information in magenta color anymore. The following screenshot shows a regular descend in VPATH:
Any ideas?
Cheers,
Stefan
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Re: VNAV Advisory Descend
Sorry to jump in, but did you make sure to enable the VNAV window in the FMS's MFD MENU page? It has three options: OFF, ON, and VNAV. This is separate from the ADVISORY VNAV option you mentioned.
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Re: VNAV Advisory Descend
Hi Stefan,
Yes, I have an idea
Go to CDU, MFD Menu key, and select VNAV in Window LSK option.
Tomas
Yes, I have an idea

Go to CDU, MFD Menu key, and select VNAV in Window LSK option.
Tomas
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Re: VNAV Advisory Descend
I've also seen some funny stuff happen with the MFD VNAV window. I find that if there's not a target altitude on the next waypoint (e.g. direct to the dest. airport, or to a visual approach RX__ fix) then it will not display most of the time. In this case, if the VNAV window is turned on from the CDU, the screen real estate will be allocated but it will appear blank. Also, one time I bumped the barber pole in descent and that made the VNAV info hide itself.
The magenta text appeared to flicker as I exceeded Vno intermittently, and then decided to bury its head, lest the chief pilot catch wind.
My PL21 experience is in Citations (it shouldn't be too different) but FWIW I recall the advisory VNAV function should enable the "circle cue" suggestion on the VSI regardless of autopilot modes, whether you're on a STAR or not. If you have valid vertical waypoints set up on LEGS, it should coincide with the required V/S shown on the VNAV window. So for example, I make a visual approach to RWY16 with a 5-mi final, then go direct "RX16" and enter an altitude of 1500' over RX16, I should see a circle cue showing me required VS (as long as Advisory VNAV is enabled) and be able to fly to that fix/altitude with VNAV.
The magenta text appeared to flicker as I exceeded Vno intermittently, and then decided to bury its head, lest the chief pilot catch wind.
My PL21 experience is in Citations (it shouldn't be too different) but FWIW I recall the advisory VNAV function should enable the "circle cue" suggestion on the VSI regardless of autopilot modes, whether you're on a STAR or not. If you have valid vertical waypoints set up on LEGS, it should coincide with the required V/S shown on the VNAV window. So for example, I make a visual approach to RWY16 with a 5-mi final, then go direct "RX16" and enter an altitude of 1500' over RX16, I should see a circle cue showing me required VS (as long as Advisory VNAV is enabled) and be able to fly to that fix/altitude with VNAV.
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Re: VNAV Advisory Descend
Hi,C525B wrote: ↑Fri May 22, 2020 9:47 amI've also seen some funny stuff happen with the MFD VNAV window. I find that if there's not a target altitude on the next waypoint (e.g. direct to the dest. airport, or to a visual approach RX__ fix) then it will not display most of the time. In this case, if the VNAV window is turned on from the CDU, the screen real estate will be allocated but it will appear blank. Also, one time I bumped the barber pole in descent and that made the VNAV info hide itself.
VNAV info in MFD will display:
- For CLIMB altitudes, as long as there is a valid CLIMB alt restriction in any wpt of the FP, that is not part of a missed approach when not flying the MAP procedure.
- For DESCENT altitudes, as long as cruise altitude is entered in PERF page and the aircraft has reached that altitude (and remains on it); OR distance to TOD is less than 50 nmiles or 2/3 of FP extension.
Both Vertical Deviation Scale and Pointer will show when:My PL21 experience is in Citations (it shouldn't be too different) but FWIW I recall the advisory VNAV function should enable the "circle cue" suggestion on the VSI regardless of autopilot modes, whether you're on a STAR or not. If you have valid vertical waypoints set up on LEGS, it should coincide with the required V/S shown on the VNAV window. So for example, I make a visual approach to RWY16 with a 5-mi final, then go direct "RX16" and enter an altitude of 1500' over RX16, I should see a circle cue showing me required VS (as long as Advisory VNAV is enabled) and be able to fly to that fix/altitude with VNAV.
- PATH vertical mode is armed (Preselector altitude is below current aircraft altitude); OR 60 seconds before the aircraft arrives at TOD if the Preselector altitude is not lowered. Providing VNAV or Advisory VNAV is enabled.
There are other restrictions for the pointer only, (ie descent rate > 100 fpm, etc). All working as expected.
Tomas
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Re: VNAV Advisory Descend
Okay, that's different than how it worked In the CJ (and the Beechjet with older Proline 4 for that matter), we didn't have to arm VPATH or reset the altitude. I thought that was the whole point of advisory VNAV. If there was a valid V-path of any sort, the VS cue and deviation scale would appear shortly before TOD without having to arm any additional modes.
Regarding the MFD VNAV window, did you see what I wrote about the text flickering and disappearing for the rest of the flight?
Regarding the MFD VNAV window, did you see what I wrote about the text flickering and disappearing for the rest of the flight?
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Re: VNAV Advisory Descend
And it's the same in the KA, 60 seconds before TOD both scale and pointer will show regardless of current vertical mode (in VNAV/Adv-VNAV)
If you dove the aircraft hence departing from cruise flight, VNAV info on MFD was gone until you get a valid TOD again.Regarding the MFD VNAV window, did you see what I wrote about the text flickering and disappearing for the rest of the flight?
Therefore, if you come back to level flight but below cruise, you can restore VNAV info by going to PERF INIT page and select a new cruise altitude with your current one.
Tomas
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Re: VNAV Advisory Descend
So why am I not seeing Adv. VNAV cues in this situation then?
Crz. alt. 9000 was entered. Vertical direct to the RX13L altitude executed, the only thing that appeared was the magenta target altitude. Still no cues after passing TOD, then I recalled your statement:
Crz. alt. 9000 was entered. Vertical direct to the RX13L altitude executed, the only thing that appeared was the magenta target altitude. Still no cues after passing TOD, then I recalled your statement:
So I initiated a descent with VS, then took this screenThere are other restrictions for the pointer only, (ie descent rate > 100 fpm, etc)
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Re: VNAV Advisory Descend
That's not exactly what happened...I was already established in a descent along the path.If you dove the aircraft hence departing from cruise flight, VNAV info on MFD was gone until you get a valid TOD again.
Therefore, if you come back to level flight but below cruise, you can restore VNAV info by going to PERF INIT page and select a new cruise altitude with your current one.
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Re: VNAV Advisory Descend
This is another restriction:
When advisory VNAV is selected, the vertical deviation scale and pointer
show when the vertical deviation is within 1000 feet of the descent path.
However, I will check if this one is effectively working as expected.
Thanks!
Tomas
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Re: VNAV Advisory Descend
Right, I executed a V-direct (because the cruise segment of my test flight ended up being very short) so that is irrelevant. I made a second test flight with a longer cruise segment so that I could watch it approach a pre-calculated TOD, but that didn't make a difference.
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Re: VNAV Advisory Descend
Well, the 1000 ft range for vertical path was not working fine, so I fixed it.
Thanks for the observation.
Tomas
Thanks for the observation.
Tomas