user error Autopilot roll issues

[Ghostrider142]

I fly the Tomcat most of the time and I hadn't flown the F-16 in awhile until tonight, but I ran into a problem that I don't remember having before. The plane will not stop rolling left or right and I cannot focus on any AG workload without constantly trimming or rolling for corrections because AP does not stop the roll. I have watched several videos over the last 4 hours and my AP switches and settings are 100% correct.

AP in the F-14 is a breeze and 100% reliable compared to the F-16, which is very surprising.

Is it really that unsteady IRL? I find that hard to believe. It's done my head in to the point I'm about to buy the F-15E just to do AG missions in peace. 

Using an X-56 with zero roll issues in other aircraft. Any outside the box ideas before I give up on this bird?

[DrDetroit]

On 12/16/2023 at 9:09 PM, Ghostrider142 said:

I fly the Tomcat most of the time and I hadn't flown the F-16 in awhile until tonight, but I ran into a problem that I don't remember having before. The plane will not stop rolling left or right and I cannot focus on any AG workload without constantly trimming or rolling for corrections because AP does not stop the roll. I have watched several videos over the last 4 hours and my AP switches and settings are 100% correct.

AP in the F-14 is a breeze and 100% reliable compared to the F-16, which is very surprising.

Is it really that unsteady IRL? I find that hard to believe. It's done my head in to the point I'm about to buy the F-15E just to do AG missions in peace. 

Using an X-56 with zero roll issues in other aircraft. Any outside the box ideas before I give up on this bird?

The AP works just fine, I use it daily  

You probably have it set to course/heading and not altitude/attitude.  I have absolutely no issues with it.

EDIT: you also have to set desired roll setting, not just pitch setting.

Edited December 18, 2023 by DrDetroit

[Furiz]

19 hours ago, DrDetroit said:

You probably have it set to course/heading and not altitude/attitude.  I have absolutely no issues with it.

I think he is talking about use of Altitude hold only.

[DrDetroit]

1 hour ago, Furiz said:

I think he is talking about use of Altitude hold only.

Alt hold works, so does Att hold, which is on the pitch switch, which also activates the AP.

He has to set roll switch as well, which I’d bet a dollar to a donut that he is default setting which is heading, not steer point (roll switch full down for steer point, not centered).

Again, F16 AP is fully functional and no issues. Def pilot error. I can fly all waypoints hands off, if necessary.

 

Edited December 18, 2023 by DrDetroit

[Furiz]

Hope he provides a track so we see whats going on,

 

as far as I see it on the AP section of the panel under ROLL there are 3 modes, HDG Sel - ATT Hold - STRG Sel which, as the chuck's guide says:

ROLL ATT HOLD: Attitude Hold in the roll axis. Aircraft will maintain the existing roll attitude, as long as the attitude is +/- 60 degrees in roll.

ED guide says this.

 

edit: Just did a small test and it holds roll like a charm

Edited December 18, 2023 by Furiz

[Lord Vader]

Hi @Ghostrider142

Just tested this myself and found no issues with the roll axis. If you feel this is still a bug, please create a short track demonstrating it and we'll have look. 

[Ghostrider142]

Thanks for the responses, I will fire it up this evening and try again. Like I mentioned I never had an issue when first learning the plane a year ago, but suddenly ran into it the other day doing practice bombing runs.

So to hold roll at level I would set AP to Pitch ALT Hold and Roll ATT Hold, correct?

[Ghostrider142]

I figured it out. It was roll not at ATT and by the time I'd get her corrected it had already come out of AP. It was a case of not having flown the Viper in a year. Thanks for the help everyone.