Possible fix for FS2020 A/P problem

[hvw 401]

First of all I have to state that I solely fly FBW's A320NEO. As I was suffering of the reported A/P problems as well, I have been investigating this problem and came up with what  for me, was the solution. After deleting the rolling cache and having FS2020 generate a new one, I made two short flights with the A320NEO (dev mode). No problems whatsoever were encountered. I of course don't know if this fix will also help for other aircraft or other users, but it worked perfectly for me. If you don't have a rolling cache, you may want to try to delete the manual cache and see if that helps. Try it, it might work for you, too.

 

Hans van Wijhe

[Car147 2,276]

Maybe your onto something, as i had just done exactly that before a flight i just did and AP worked fine. ( I just made a post about this AP A320) and was wondering if they were tweaking things behind the scenes.) But like you say, i suppose it's possible clearing the rolling cache maybe did resolve it.

Edited November 27, 2020 by Car147

[leprechaunlive 1,852]

2 minutes ago, Car147 said:

Maybe your onto something, as i had just done exactly that before a flight i just did and AP worked fine. ( I just made a post about this AP A320) and was wondering if they were tweaking things behind the scenes.) But like you say, i suppose it's possible clearing the rolling cache maybe did resolve it.

If thats really a fix, thats amazing. How random is that? If it works, it makes NO sense 😁

[BackboneOne 47]

what if i dont have a rolling cache?

 

[DAD 2,650]

1 minute ago, BackboneOne said:

what if i dont have a rolling cache?

 

Create one. And delete it. See how it works 🙂 

[DAD 2,650]

Just now, DAD said:

Create one. And delete it. See how it works 🙂 

Seriously. I just don’t get it. Had cache enabled so far and did a perfect flight from lowi to Korfu in the dev modded neo. All fine. Just started a TBM flight from Hammerfest but coincidentally (in terms before I read this hint) deleted the rolling cache before. All fine with the TBM. Will check next with neo

[hvw 401]

BackboneOne,

12 minutes ago, BackboneOne said:

what if i dont have a rolling cache?

 

Do you have a manual cache? If so, delete that one and see if that helps any.

[marsman2020 1,310]

I find it highly unlikely that a scenery cache has anything at all to do with how the autopilot works.  The devs said in the recent Dev Q&A that the cache is checked for currency and should return exactly the same data as the scenery servers.

Define "fine" please.  If you spin the heading bug 180 degrees, do you get a nice smooth 180 degree arc, or does it slow down the turn 30-40 degrees before the end point, creating a weird asymmetric turn that takes forever to reach the set heading?

I turned all streaming data OFF and put the entire sim in Offline Mode while creating the video of the current AP behavior that I made yesterday, so I highly doubt the streaming scenery of scenery cache has anything to do with this.

 

[jrw4 624]

Deleting the rolling cache may work for some people, but certainly did not for me. Actually, in the steam gauge C172, the AP does enter a standard rate turn (according to the turn coordinator gauge) correctly over a good range of air speed, but it's those last 30+ degrees where the rate slows too much as the AP anticipates the roll out. The AP has a hard time intercepting an ILS final approach course as a result, and flies through the localizer before correcting back on course when attempting an intercept at the common 30 degree intercept angle.

As someone said on another posting here, this will give us an excellent opportunity to hone our hand flying skills.

[webranger 186]

Ditto for me with deleting the manual and rolling cache.   Using the FBWire I am still not able to get the AP to follow the flightplan.    Going back to the vanilla A320 to test it.

[Silicus 877]

Workaround with the FlyByWire A32NX mod (Use the latest dev build to be sure):

   1. Spawn Cold and Dark

   2. when loaded in hit "esc" then "save" and name flight. 

   3. Immediately hit "load" and select flight.

   4. It will reload then proceed as normal flight

Another workaround. Miles may vary.

[IAhawkeyeDDS 158]

[IcemanFBW 721]

3 hours ago, marsman2020 said:

I find it highly unlikely that a scenery cache has anything at all to do with how the autopilot works.  The devs said in the recent Dev Q&A that the cache is checked for currency and should return exactly the same data as the scenery servers.

Define "fine" please.  If you spin the heading bug 180 degrees, do you get a nice smooth 180 degree arc, or does it slow down the turn 30-40 degrees before the end point, creating a weird asymmetric turn that takes forever to reach the set heading?

I turned all streaming data OFF and put the entire sim in Offline Mode while creating the video of the current AP behavior that I made yesterday, so I highly doubt the streaming scenery of scenery cache has anything to do with this.

 

Correct, the scenery cache has absolutely no impact on aircraft performance. The issue itself is non-deterministic and any "improvements" noticed after turning off the cache are likely coincidental (and temporary).

[cmpbellsjc 2,960]

5 hours ago, hvw said:

First of all I have to state that I solely fly FBW's A320NEO. As I was suffering of the reported A/P problems as well, I have been investigating this problem and came up with what  for me, was the solution. After deleting the rolling cache and having FS2020 generate a new one, I made two short flights with the A320NEO (dev mode). No problems whatsoever were encountered. I of course don't know if this fix will also help for other aircraft or other users, but it worked perfectly for me. If you don't have a rolling cache, you may want to try to delete the manual cache and see if that helps. Try it, it might work for you, too.

 

Hans van Wijhe

Back in the FSX days, sometimes their were issues with PMDG birds not capturing/tracking ILS courses properly on autopilot. It was discovered by Ryan (Tabs) with PMDG that deleting the FSX scenery cache and letting FSX rebuild one fixed the issue. 

If the issue is somehow similar in MSFS as it was in FSX, then this workaround is certainly plausible if they work in a similar fashion.

[hvw 401]

9 hours ago, cmpbellsjc said:

Back in the FSX days, sometimes their were issues with PMDG birds not capturing/tracking ILS courses properly on autopilot. It was discovered by Ryan (Tabs) with PMDG that deleting the FSX scenery cache and letting FSX rebuild one fixed the issue. 

If the issue is somehow similar in MSFS as it was in FSX, then this workaround is certainly plausible if they work in a similar fashion.

From my betatesting days of Microsoft FS(x) (1990-2006)  I suddenly remembered we used to clean out the cache(s) when we ran into these similar kind of problems. Of course this most probably won't work for everyone or every aircraft, but at least deleting the rolling cache and regenerating one so far worked for me. My idea with MSFS2020 was/is, that with the "old" cache the latest update might have read some "wrong" data from the cache causing this irrational behavior of the A/P. It was just a thought. If it helped, great. If it didn't work, tough luck. Now let's see which anomaly Asobo has got next in line for us 🙂 

Have a good one,
Hans