Autopilot Wallowing

[pacecapt]

I have an HDX system with Dynon 42 (Roll and Pitch) Servos installed on my Zenith CH-750 Cruzer. The system has the latest software version installed and I typically run it in simplified mode as I only fly VFR. Whenever I engage the autopilot (especially in smooth air) it tends to start wallowing along my course. It does not matter whether I have it in HSI +Alt or Track + Alt the wallowing is the same. The Autopilot has the default settings and I have not changed anything on it. Any recommendations as how to reduce or eliminate the Wallow?

 

[Marc_J._Zeitlin]

Any recommendations as how to reduce or eliminate the Wallow?

What's your definition of "wallow", and it sounds like you haven't gone through the Autopilot Tuning Procedure yet...

 

[airguy]

Does your installation use the capstan and cable, or the arm on the servo with a direct mechanical connection?

 

[andresmith76]

The link to the Autopilot Tuning Guide as earlier suggested. Select the "Installation Guides" tab and you'll find it 3rd down on the list:

Dynon Avionics | SkyView Documentation

Dynon Avionics' User Guide and Installation Manuals.

dynonavionics.com

Andre'

 

[pacecapt]

What's your definition of "wallow", and it sounds like you haven't gone through the Autopilot Tuning Procedure yet...

Maybe I didn't use the correct term...the plane hunts (left and right) of course when in straight and level flight.

 

[pacecapt]

Does your installation use the capstan and cable, or the arm on the servo with a direct mechanical connection?

It has Arm on Servo for both Pitch and Roll.

 

[pacecapt]

The link to the Autopilot Tuning Guide as earlier suggested. Select the "Installation Guides" tab and you'll find it 3rd down on the list:

Dynon Avionics | SkyView Documentation

Dynon Avionics' User Guide and Installation Manuals.

dynonavionics.com

Andre'

I did the setup and everything works in when doing it. But it hunts (left and right) of course when in straight and level flight.

 

[Marc_J._Zeitlin]

I did the setup and everything works in when doing it. But it hunts (left and right) of course when in straight and level flight.

You explicitly said "The Autopilot has the default settings" which implies that you didn't "tune" anything during the tuning process. Some of the parameters will help with maintaining track without oscillating back and forth (I assume just a few degrees).

 

[Steveden]

I found that for my cub I had to reduce the default settings in order to keep it from hunting back-and-forth. It got worse as I increased them

 

[AlanR]

You need to consider the 'default' settings to be the starting point for tuning the Autopilot.
I still keep occasionally tweaking my autopilot settings 5years on!