[BUG] Autopilot systems not functioning after MSFS update

[Teslix]

Mod Version

Latest Dev Version from Installer "built": "2020-11-24T08:08:38+00:00", "ref": "refs/heads/master", "sha": "b570de8c53cd5b52a21c81f8120bfa57d8c53830", "actor": "wpine215", "event_name": "push"

Describe the bug Multiple issues on my first flight today after downloading the FS2020 1.11.6.0 update, downloaded the latest Dev build before flying:

1. After takeoff, engaged AP but the aircraft wouldn't follow the flight plan in managed heading.
2. Set heading to manual, aircraft would not bank right to new heading (straight line).
3. Tried left heading instead, plane banked ~40 degrees to setting.

To Reproduce

1. Filed flight plan through FS2020 world map
2. Start-up, taxi, takeoff as per normal
3. Issues noticed after turning on auto pilot systems.

Expected behavior

Expected aircraft to bank right and take up the managed heading selection as per the flight plan.

Actual behavior

Aircraft maintained current heading, would not respond to a right turn in heading selection mode and banked over 40 degrees when selecting left heading instead. Flight plan indicator on the FD shows as straight line to infinity. AP will not capture.

References

N/A

Additional context

Was this working before/when did the issue start occurring? Not an issue until today's update.

Is this a problem in the vanilla unmodded game? I've repeated the same flight / flight plan without the A32NX mod, and the issue does NOT exist there.

In the first screen shot below, I've engaged the AP and the aircraft immediately banks a little to the left, when I should go right. It then maintains a straight line and immediately, the flight plan switched to a waypoint 3 down the list but doesn't track in that heading.

In the next screen shot, I've switched to heading selection mode and made a selection for a right turn, but the aircraft is not responding.

[drforweb]

Same problems with AP described above after downloading the patch.

[Benjozork]

the flight plan line points straight and never changes.

That's the new track line.

[Teslix]

the flight plan line points straight and never changes.

That's the new track line.

Ack, but it shouldn't show up then in managed heading mode, it should display the flight planned route, which was behind me by that time.

[Benjozork]

TCAS gave off an error while aligning (orange code in display), but eventually the systems came alive.

This is normal and has been that way for a long time.

[Teslix]

TCAS gave off an error while aligning (orange code in display), but eventually the systems came alive.

This is normal and has been that way for a long time.

I can't say it's been that way for me. Once I switch the TCAS alignment switches, it usually displays TCAS align in X min until the system aligns, then dissapears. It switched from that to "TCAS ERROR" in orange writing for a few minutes, then the systems came alive.

[Benjozork]

There is no such thing as TCAS align.

Can you take screenshots of the behaviour ?

[Benjozork]

the flight plan line points straight and never changes.

That's the new track line.

Ack, but it shouldn't show up then in managed heading mode, it should display the flight planned route, which was behind me by that time.

If you have a reference for the correct behaviour, please open a separate issue.

[Teslix]

There is no such thing as TCAS align.

Can you take screenshots of the behaviour ?

Correction (am not a pilot) IRS align.

[Teslix]

I'll go in and try to get some specific screenshots.

[floufille]

Yes, i've this, but, when i've retried, it works

[Benjozork]

NAV TCAS FAULT is correct behaviour when IRSs are not aligned.

[floufille]

For this one:

2. After takeoff, engaged AP but the aircraft wouldn't follow the flight plan in managed heading.

Indeed, i've this kind of issue :

[Teslix]

NAV TCAS FAULT is correct behaviour when IRSs are not aligned.

So, this may be cause I don't typically start the engines prior to the IRS aligning, but I get this TCAS fault MASTER CAUTION warning only when the engine is started prior to IRS align. If this is the normal behaviour, then I'll remove it from my bug. The remainder of the AP issues are still an issue.

[A320PHX]

For this one:

1. After takeoff, engaged AP but the aircraft wouldn't follow the flight plan in managed heading.

Indeed, i've this kind of issue :

Strange, for me it heading to the left at about the same angle... Also, this happens when I removed the A32NX mod. I think Asobo might have borked something up...

[TheoBearman]

Just tested with v0.4.1. and not having any issues with the AP following the route correctly in managed heading mode. Haven't tried on the vanilla.

[Road-to-Hell9]

I have the same problem on the alpha, (24/11/2020)

[Benjozork]

I have the same problem on the alpha

What alpha ?

[SimGuy9590]

Once I turn AP on, it wants pulls a continuous, hard left turn.

[jsid87]

I have the same problem after new update. First after engaging AP airplane banks hard left,then I turn off and on AP, after that airplane doesn't follow fligt plan. I have latest master version.

[messer79]

I confirm. When on AP in HDG mode the plane barely turns right. It also doesn't keep the course which is shifted to the left.

[Benjozork]

Hello, please refrain from adding comments if your issue is the exact same, unless you have new information like how to reproduce it more accurately. Use the thumbs up reaction on the main post instead. Too many comments makes it hard for us to dig through.

[vlbreda]

Tested both the dev version and the stable version, both installed using the downloader shortly after 8pm CET. Dev version has the issue of not following the flightplan, stable version however seems to be working fine. Maybe not all hope is lost yet;)

[Teslix]

I've updated my original post, since I've had time to try now. When the mod is removed, the AP system works fine, appears to be an A32NX issue only.

[pareil6]

Already shared this on Discord but just in case it gets lost, here's what I found trying to figure this out - when you turn the AP on, whatever the FD is directing laterally seems to become the 'middle' - ie. if you turn the AP on with the FD line pushed hard left, it'll treat that as wings level and try to bank further left for any left turn and back towards true level for a right turn. If the FD isn't commanding a turn when it's first turned on, it seems to behave roughly as expected.

Reproduced by starting C&D, lining up on the runway with HDG set to a hard-right bank, taking off normally and turning the AP on once above accel height, then trying to turn back left which only gets as far as levelling the plane but never actually banks to the left. Doing the same thing with the heading bug set straight on takeoff allows the plane to turn both ways after accel height.

I've noticed some people on Discord reporting that the AP sort of works but will consistently fly slightly to the left/right of the flight plan, which seems consistent with what I'm seeing here - if the FD is centered wrong, it'll pull 'level' (by it's wrong definition of level) once it's on the path, but will drift one way, so will correct by banking left/right to compensate, until it hits actual level flight, so you end up in some accidental equilibrium as a result.

Also, I've tested starting on the runway and starting C&D (since this came up on Discord), both seemed to have the same behaviour.

[TheoBearman]

Hi @pareil6, can you confirm what versions of the aircraft you did these tests on? Dev, latest stable and/or vanilla?

[pareil6]

Latest-ish dev, SHA b570de8c53. Only occurs with the mod, tested with the vanilla A320N and this bug didn't occur.

[Teslix]

I'm not sure if it's a concurrent issue or not, but when AP was selected (while in managed heading mode), the MCDU flight plan page skipped the FS2020 custom waypoints D0 and DLast (custom departure WPs) and went direct to the first real life WP, VLR (but the aircraft did not bank to go there).

[fingerratte]

Same here, after start, AP on - and my plane tried to heading left, hard left with > 40 Degrees, and does not follow the programmed route, but holding the high. He accepted V/S and altitude changes. I play with self loading cargo. I used your Dev package (master)

[Benjozork]

Again, please refrain from adding comments if your issue is the exact same, unless you have new information like how to reproduce it more accurately. Use the thumbs up reaction on the main post instead. Too many comments makes it hard for us to dig through.

[Lvandus17]

yep it really wants to follow the lateral flight director (and possibly ignore vertical? or the horizontal might just be too aggressive to let the vertical have any say) even when it's horrifyingly wrong. Starting from cold and dark, supposed to have a 90ish degree left turn after takeoff on departure, hand flew the first turn past the waypoint, levelled the wings before enabling AP, but as soon as AP is enabled, 60+ degrees hard left bank in a downwards spiral (assuming the latter is caused by the former and vertical unable to compensate.)

Starting spawned in the air without a flight plan allowed selected heading to work (apparently) correctly; I'm going to try taking off with in selected heading set to runway heading before turning on the AP, then switch to managed, see if that works as a temporary fix? Also planning to test a straight out managed heading departure; possibly it's merely the presence of the bank as the first step in the flight plan that the AP is getting hung on.

[Teslix]

yep it really wants to follow the lateral flight director (and possibly ignore vertical? or the horizontal might just be too aggressive to let the vertical have any say) even when it's horrifyingly wrong. Starting from cold and dark, supposed to have a 90ish degree left turn after takeoff on departure, hand flew the first turn past the waypoint, levelled the wings before enabling AP, but as soon as AP is enabled, 60+ degrees hard left bank in a downwards spiral (assuming the latter is caused by the former and vertical unable to compensate.)

Starting spawned in the air without a flight plan allowed selected heading to work (apparently) correctly; I'm going to try taking off with in selected heading set to runway heading before turning on the AP, then switch to managed, see if that works as a temporary fix? Also planning to test a straight out managed heading departure; possibly it's merely the presence of the bank as the first step in the flight plan that the AP is getting hung on.

My initial issue arose from a straight out departure and then turning on AP into managed heading mode to turn towards my flight plan, same issues. It’s looking like the attitude that the aircraft takes on AP ON is directly related to the initial attitude prior to engaging it. People that engage it in level flight seem to be banking left a little as a result, and people who engage it in a turn seem to aggravate it and bank steeper into a dive.

[vstaritz]

can confirm this behaviour is also present in the earlier dev build i use which is #6befad1 for Nov20

[mikecbr]

@vstaritz could you please send me that build please ?

[Teslix]

I’m not sure how the installer works, but I tried overwriting the dev version with the stable version about 30 mins ago, and the issue is still there.

[doolok]

Just thought I'd verify what everyone else is experiencing.... With the Dev build, after departing, I climb to 5000 in manual mode, then enable the AP button. The plane did not turn to follow the selected course. I had to enable heading mode and manually turn it to get it started. It followed the waypoints, albeit off a few miles from course, but was very troublesome to get it to follow correctly.

I'm going to try the stable build here shortly, see what it does.

[LoungeFlyZ]

I tried this out KSEA->KPDX leaving KSEA 16L with the generated route from the world map.

I noticed that when engaging the autopilot it stayed heading in the direction it was going and also had a slight left tilt going. However, when I manually hit the "Level off" (push I think on the V/S knob) it leveled the aircraft and leveled the wings to the horizon also. It flew the rest of the route as expected.

[jsid87]

I noticed that problem with AP not following route and banking hard left only happens when starting from cold and dark state. When I start from the runway everything is ok.

[duckietm]

Could this be related to the problem i already had before the update ?

https://github.com/flybywiresim/a32nx/issues/1967

[AlphaMA1]

Problem only exists when starting cold and dark. I DID have the same problem with the vanilla A320 (from c & d start) after removing the A32NX mod too. It's NOT isolated to the A32NX on my machine. There are several users on the flightsimulator.com forum reporting similar AP issues with the vanilla A320, so this may well be an in-sim issue in the flight model.

[dc1ps2]

I also encountered the same problem. After planning the flight plan, it is expected that from YSSY-YMML, the AP (automatic flight) will be turned on after takeoff, and the aircraft will not turn according to the planned route. Repeated attempts to turn off the AP and restart it. He will only fly straight in the direction the nose of the aircraft is currently facing. Even if the automatic flight is cancelled, the aircraft is manually controlled to turn, and the AP is activated again, he will only automatically return to the level flight state and go straight forward.

The video I recorded is provided below for the reference of the development team, thank you for your unpaid work and dedication.

https://youtu.be/7o9zwCkb1-I?t=1799

by 1.11.6.0 version and A32NX version is Development version build info: { "built": "2020-11-25T09:44:14+00:00", "ref": "refs/heads/master", "sha": "29398d31d99ff98313277c2bef2991ec21d13ab4", "actor": "wpine215", "event_name": "push" }

[Knallhartmuth]

Same issue. Started cold and dark, after putting thrust lever in thrust climb and activating the AP the aircraft banked hard to the right and didn't follow the flight plan. FL was set to 100 but the Airbus stopped climbing at FL90 and started descending. Manual heading didn't work also. A32NX 4.1, MFS 1.11.6.0

[Teslix]

Problem only exists when starting cold and dark. I DID have the same problem with the vanilla A320 (from c & d start) after removing the A32NX mod too. It's NOT isolated to the A32NX on my machine. There are several users on the flightsimulator.com forum reporting similar AP issues with the vanilla A320, so this may well be an in-sim issue in the flight model.

That's definitely weird that people are getting different results on this. C&D start with mod, I get the issues, delete the mod completely, C&D start with the vanilla A320neo, same flight plan/procedure and the issue is gone for me. Put the mod back in, issue returns.

[Benjozork]

There are multiple issues at play here and how they each interact with the mod and what each is caused by is still unknown atm. We have one issue narrowed down and are looking into what's causing it, but it's only a fix for a small part of the AP problem.

[ntlgr]

In my case with the latest Dev, apart from not following the FP, the aircraft after AP engagement climbed and maintained 4500 and kept a shallow, continuous turning left bank (3 degrees or so). It was set to climb to 8000. There were no ALT constraints in the flight plan. I am happy to help out with testing if the team needs help.

[Knallhartmuth]

Problem only exists when starting cold and dark. I DID have the same problem with the vanilla A320 (from c & d start) after removing the A32NX mod too. It's NOT isolated to the A32NX on my machine. There are several users on the flightsimulator.com forum reporting similar AP issues with the vanilla A320, so this may well be an in-sim issue in the flight model.

That's definitely weird that people are getting different results on this. C&D start with mod, I get the issues, delete the mod completely, C&D start with the vanilla A320neo, same flight plan/procedure and the issue is gone for me. Put the mod back in, issue returns.

I tried this a few moments ago. Without the mod the AP works but it behaves not as expected. Altitude works fine. Also it somehow tries to follow the flight plan without banking extremely, BUT... the aircraft is way offset the route, wheather or not it will arrive at the destianation eventually I can't tell yet. I had this offset before, but not as extreme as it is now. And it seems not to follow the manual heading accurately (with A32NX 4.1 it doesn't react on manual heading input at all...)

Manual Heading. Aircraft seems not to follow heading bug

When engaging Nav mode again after manually following the route. Aircraft leaves route but seems to go roughly in the correct direction. But generally AP reacts on inputs.

Edit: The offset of the aircraft to the route is about 7NM to the right

[TomMaverick]

Cold and dark start. My Flight Director is always showing full left and the Aircraft banks to the left (but 50-60°+) going full circles and losing altitude. After a few minutes in the air flying the SID by hand I activated the AP again and it only holds the current heading (with a slight left and right rocking, FD still showing full left) and the set altitude (NAV). ATHR seems to be working normally.

MSFS 1.11.6.0 A320NX is current DEV (05:05pm UTC, 25. Nov)

[pareil6]

I've had another shot at testing this, and ended up with different results to my earlier comment: this time, two attempts spawning on the runway led to the AP/FD working as expected, whereas four attempts spawning C&D didn't. I did also notice the initial offset the FD seems to show isn't actually anything to do with how far you are from where the AP is supposed to be going (ie. difference vs. manual heading or flight plan route depending on which is enabled), which was my assumption last time.

However, when I had the IRS alignment set to instant instead of realistic, the lateral offset in the FD seemed to be far smaller (ending up with a sub-5-degree bank) than when the IRS alignment took longer (with a 30+ degree bank both times). I'm wondering if there's some correlation between time spent sitting at the gate and/or taxiing with how badly the offset seems to be, which might explain why spawning on the runway seems to help for some people but not others?

(All done on the same dev version as last time, b570de8.)

[Pridechaser]

Had the same issue every flight plane does not follow course plan after hitting AP button seems it just keeps flying str8 also the rocking of the plane is back also.

Dev mod not stable version forgot to note that, on a cold start and departing.

[Knallhartmuth]

I'm wondering if there's some correlation between time spent sitting at the gate and/or taxiing with how badly the offset seems to be, which might explain why spawning on the runway seems to help for some people but not others?

(All done on the same dev version as last time, b570de8.)

That may be true. In my flight is was really long at the gate, programming MCDU, doing the checks and waiting for traffic. The offset was quite big.

[A320PHX]

When starting cold and dark for me, the plane entered a sharp bank and dove into the ground. When starting at the runway, the plane still only vaguely followed course. I though maybe it would eventually fix itself, but it did not. As the flight progressed, it remained off course and would sometimes turn again, making the offset greater.