A320X Developer - Autothrottle disengaging during cruise

Sometimes I let the plane cruise for a long time while doing other things AFK. On some flights (not all) it happens that the Autothrottle disengages for some reason and I find the plane in overspeed situation. Anyone has an idea what could trigger that or if it’s a bug? There’s no control binding for A/THR and it happens both in managed and selected mode.

Did you set your thrust lever into CLB position and keep it there?

Yes, I also setup the throttle in a way that that the zone for CLB is rather big.

The problem is, I never experienced an unexpected AT disengage so far. So we need to find out what the problem is.

  1. Is the lever still in CLB position, when the AT disengages?

  2. When you’re in Cruise, does everything behave normal? Correct speeds, thrust etc.

  3. Could you try several flights without any other mod or custom livery in your community folder.

  4. Did you set some deadzones for you controller in MSFS sensifity settings?

  5. When you say you made the CLB zone in A32NX EFB throttle calibration rather big, how big?

  1. Yes.
  2. Yes.
  3. Yes, I’ll try that.
  4. I have set deadzones for every axis (but not for trim on the throttle)
  5. Range 0.05 (0.05 - 0.15)

0.05 seems a good range. You can also check, if there’s something else bound to your throttle/thrust in your MSFS settings. Sometimes MSFS is doing strange things when updating.

I see from your post history that you have a Saitek X55 - me too.

The throttle has a known design flaw where phantom inputs can occur, usually when it is connected to USB3 or an underpowered USB Hub.

Can you try connecting direct to a USB 2 port, or dimming the LEDs using the programming software?

They do, had to remove all button assignments (especially the sim rate, wasn’t cool when it changed to 3x seconds before touchdown…). Maybe the throttle input itself began to fluctuate, but on the calibration screen I couldn’t reproduce that. It’s very steady. I have it on a powered USB3 hub, but I’ll try an USB2 port and powered hub as well.

I had that for a couple times also last week and run in an overspeed situation. next to that it, with the throttle in CB mode, LVR CLB was still flashing. I managed to get the A/THR enabled again after I managed the speed.

I updated to the development release feb195b and it didn’t appear anymore. I also calibrated the throttle with slightly better ranges.

to day for the time the a320 will not follow the flightplan and the AP doesnot work correctly.
it fails in all 3 a320 stable and development and the third one.
is it the plane are msfs? strange never had this before. I have not changed anything.