Autopilot keeps disengaging NAV mode (VOR-to-VOR navigation)
-
Did some flying today flying in South Africa in the Commander with twin MX 170B and the RNAV 511, weather was LIVE and clear and fine.
First leg was FAPA to FAEL (57nm) and set the 'ELV' VOR as my NAV1 to get me to FAEL. I initially climbed to about 2000ft and the NAV dropped once, understandable as quite low altitude tbf. I then continued climbing to 6000ft and during cruise it dropped again, cant remember exactly but 30nm out. It then also dropped NAV about 15nm out with me at 6000ft with clean line of sight which seems unlikely that it would be a poor signal? I also had NAV2 tuned the same and the needle seemed rock solid and not showing signs of signal loss.
Second leg was from FAEL to FAUG using the same VOR for outbound. Weirdly as I climbed out it dropped again at about 15nm on the outbound.
In other legs I used the RNAV 511 and this 'holds' signal all the time but it does seem to lose signal SOFT lock and then CAP again and stays in NAV. So still I guess losing signal briefly but does its best to recapture and then proceed.
Conclusion, not really sure but the degradation does seem to either be over sensitive or there is some other factor at play. I really couldn't see a reason for losing signal and NAV at about 15nm in and out at decent altitude and clear line of sight.
Apart from that it was 6hrs of bliss touring around South Africa in the 114 ... such a great aircraft.
-
@Black-Square
I did another two test flights today to see if I could discover some pattern.-
I took the standard Piper Dakota for a VOR-to-VOR flight at 6500 ft.
Empty Community and Community2024 folders.
No external programs running (no SPAD.neXt, TrackIR5, MSFS AutoFPS, Navigraph Charts, Little NavMap etc.).
All standard MSFS2024 hardware bindings and mouse control.
Observations: Autopilot NAV did NOT disengage during climb-out and cruise (1h30m). -
Second flight was with the Just Flight BAe146-100 on the same VOR-to-VOR route at 7500 ft.
Selected applicable and my usual "standard" Add-ons in Community and
Community2024 folders via Addons Manager.
External programs running: SPAD.neXt, TrackIR5, MSFS AutoFPS.
Observations: Autopilot V/L Mode did NOT disengage during climb-out, cruise and ILS approach (about 50 min).
Conclusion: standard aircraft (only one tested: Dakota) and some but not all third-party aircraft don't show this issue, while several third-party aircraft are affected. It seems to me that a relationship between the Commander 114 (amongst others) and the disengaging NAV mode can not be excluded.
This NOT an accusation that something is wrong with the aircraft. On the contrary, it might be the perfectionist and advanced design of the systems that proof to be too good or sensitive for what MSFS2024 can deliver. But I am convinced Nick has taken that into consideration. It just came up as a thought …...
BTW one advantage of doing so many test flights is that you get to learn and enjoy this wonderful gem of an aircraft. For me this is the best and most enjoyable single engine GA aircraft, though I must say the TBM850 comes very close.
@HansDeVlieger
I did tests some time ago with several aircraft. Here is a copy of what I found from the related MSFS forum entry:
Found the same problem with the following aircraft:BKSQ Caravan PMDG DC-6 NAMS YS-11 Default Beech King Air C90 GTxHowever I did NOT find the problem with the following aircraft:
Beech Baron G58 Beech King Air 350i Beech Bonanza G36 Saab 340 Cessna Citation CJ4 Cessna Caravan EX SWS Kodiak TBM 930I did all tests “Ready for take-off” from KSNA with 115.3 OCN Oceanside VOR, flying to and from the VOR in about 3-5000 ft.
-
-
@HansDeVlieger
I did tests some time ago with several aircraft. Here is a copy of what I found from the related MSFS forum entry:
Found the same problem with the following aircraft:BKSQ Caravan PMDG DC-6 NAMS YS-11 Default Beech King Air C90 GTxHowever I did NOT find the problem with the following aircraft:
Beech Baron G58 Beech King Air 350i Beech Bonanza G36 Saab 340 Cessna Citation CJ4 Cessna Caravan EX SWS Kodiak TBM 930I did all tests “Ready for take-off” from KSNA with 115.3 OCN Oceanside VOR, flying to and from the VOR in about 3-5000 ft.
@George-Curious Do you use FSUIPC, SPAD. neXt, MobiFlight or Axis-and-Ohs, just to try to zoom in? In any case, the issue doesn't seem to be related to any aircraft or developer in particular then.
-
@George-Curious Do you use FSUIPC, SPAD. neXt, MobiFlight or Axis-and-Ohs, just to try to zoom in? In any case, the issue doesn't seem to be related to any aircraft or developer in particular then.
@HansDeVlieger
I don't use any add-ons besides aircraft and sceneries. -
So, also those won't probably cause the issue.
-
@George-Curious Interesting that the Default Asobo King Air does this. I'm away-from-sim for a few days, but I might try to repro that. If I'm able to, I'll tag the moderators on my original bug post in the FS2024 forums.
I also might try to whip up a quick .NET app that monitors some of the NAV/VOR SimConnect variables and see if there's anything interesting going on. My hypothesis is that the VOR signal is intermittently dropping for a short period of time (seconds? milliseconds?), and since the autopilot can't receive it, it reverts to ROL or some other default mode. Perhaps some autopilots have a longer polling interval for receiving the signal than others, and are more resilient to signal drops. Since BKSQ likely uses common code for most/all planes, it might explain why I'm able to repro this behavior on all of them. All wild guesses, but it sort of makes sense as I think about this.
-
By they way, it seems like we pretty much ruled out everything (SPAD, FSUIPC, signal degradation, many different plane developers, hardware bindings and valid in-sim situations)...
I'm slowly getting desperate. During flight I can just substitute NAV with HDG and it's not a biggie, but it repeatedly disconnected nav/gs on ILS approaches, which almost run me into mountains
As such... did any one of the impacted people try reinstalling the sim or at least "repairing files"? I prefer to ask before trying it myself because I pretty much have the same install since MSFS2024 appeared and I'm not sure anymore if I didn't tinker with it in some way. -
Yesterday I actually started wiring up the app I mentioned to monitor SimConnect variables. I had it polling the VOR signal strength every tenth of a second. No correlation quite yet as I had several disconnects while monitoring, but no drop in strength that I could see. I'll see what other variables I can monitor today.
I'm guessing my chances of finding something is pretty slim, but it's a good refresher for me with C#/.NET; it's been a while.
-
Thanks for the status report. I'm still testing, but I might have found something. Might have gotten lucky a few flights and am afraid to jinx it.
What I did was going the "repair files" route but before I clicked the button I decided to back up my Community folder. So I renamed it, clicked repair files and launched the sim. It created a new Community folder creating new files/folders for the Marketplace purchased streamed content (StreamedPackages). Then I just added my old custom content from "Community" and "Community 2024", leaving the new streamed content Marketplace installations intact and... for now it works.
Maybe, just maybe it was a corrupt general sim file or some faulty streamed content installations (I have multiple sceneries purchased on the Marketplace, so maybe on of them messed up nav data?). Or I'm just lucky and the disappointment will strike soon
-
Thanks for the status report. I'm still testing, but I might have found something. Might have gotten lucky a few flights and am afraid to jinx it.
What I did was going the "repair files" route but before I clicked the button I decided to back up my Community folder. So I renamed it, clicked repair files and launched the sim. It created a new Community folder creating new files/folders for the Marketplace purchased streamed content (StreamedPackages). Then I just added my old custom content from "Community" and "Community 2024", leaving the new streamed content Marketplace installations intact and... for now it works.
Maybe, just maybe it was a corrupt general sim file or some faulty streamed content installations (I have multiple sceneries purchased on the Marketplace, so maybe on of them messed up nav data?). Or I'm just lucky and the disappointment will strike soon
