FBW A320 altitude, airspeed, and auto pilot issues


So as the topic says I have an issue with the altitude, airspeed and auto pilot in the FBW A320

I am using the most up to date stable erosion (7.0)

I did a test flight today because I have been waiting since the last update for some add ons to updated ect.

Everything looked great and seems fine but for some reason when I click the auto pilot button after take off it does not light up or says engaged but the plane just flys straight ignoring the set altitude and flight path.

I set up an IFR flight and in which it did not follow.

Also adjusting the selected altitude does nothing. I normally fly managed air speed mode but for some reason it ignored that as well and set its self to 350kts. And was acting very odd.

Has anyone be experiencing this with the latest stable version? Basically In a nut shell I can’t fly IFR using autopilot. Setting altitude and or air speeds does nothing. I had to manually fly.

Appreciate any input!

Good morning,
I would guess you missed a lot of the Airbus logics basics. If you’re not able to engage the Autopilot after takeoff, most probably you set it to early and most probably your airspeed is not safe at all.

If you’re not engaging the AP, the plane is clearly flying straight with your initial v/s and is not following the flightplan.

ignoring new altitude and/or heading and so on….well….if the AP is disengage, your plane do nothing whatever you set at the FCU.

My conclusion is, first of all you need to clarify if you meet the basics for engaging the AP. Maybe a screenshot would be a good idea, because we can actually see what’s wrong with your settings.

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Does your flight plan have a solid green line or a dotted line? If you see a dotted line you are not in NAV mode. I had to change settings to have my mouse work properly en see een Arrow hovering over the NAV knob.

If you’re in OP CLB for example (see FMA on PFD) and you’re flying manually it’s your responsibility to control airspeed with pitch (basically follow the flight director guidance). The reason is because this mode is using thrust mode for ATHR which means climb thrust in that case.

Similar applies to OP DES where idle thrust is commanded. Happens rarely to real world pilots as well that they forget this.

This is the reason why usually when not following the flight director, both FDs are turned off. This forces the ATHR to speed mode.

In regards to the AP, I guess you’re probably inside a protection (high angle of attack or high speed) which prevents the AP to be engaged.

Other than that you can engage the AP when you’re higher than 100 ft RA and after 4 or 5 seconds after lift-off but not earlier (don’t remember exact time right now).

As a general hint: it helps a lot to understand what is going on when you provide a screenshot or video.

The A32NX got quite more realistic with the new stable version in terms of AP modes. This can be a challenge for new users because the default Airbus is less realistic but more indulgent in that sense.


Thank you all for the replies! I’m assuming it’s like you said the AP mode got a lot more realistic with the latest stable release so it’s all new to me now!! I will test out what you have suggested and if I continue to have issues I will provide video/screen shot!

Thank you!

I think we have something that could help you get familiar with the updated systems: Overview - FlyByWire Simulations Documentation