Dynon Skyview autopilot

[flyenforfun]

I have an RV-8 with the Dynon Skyview system that I have been flying for three years now and I have a problem with the altitude hold that I've had since day one. In smooth air the autopilot pitch axis pulses and it drives me nuts. I've gone through the tuning procedure many times and tried different setting but still no luck. The only thing the various setting seem to do is speed the pulse up or slow it down just a little. At any rate nothing seems to help I'm starting to wonder if its mechanical or something electronic in the ADAHRS or pitch servo.
Roll axis seems to work fine. Any suggestions would be appreciated.
Matt

[woxofswa]

I upgraded my -10 to the linear pitch servo before I even flew, so I can't give a before and after comparison, but I can say that through a wide range of weights and conditions, I have been 100% happy with the performance of mine.
You might consider trading up to the linear actuator if you don't have it already.

[Jrskygod]

Same here minor pitch pulses anoying in smooth air.

[Carl Froehlich]

"In smooth air the autopilot pitch axis pulses.."

This in not normal. Recommend sending Dynon technical support a note. Other than replacing the pitch servo in my RV-10 to the linear actuator (Dynon replaced for free), the Dynon autopilot has been flawless.

Carl

[flyenforfun]

I'll give them a call and see what they say
Thanks

[Toobuilder]

I get the same thing with my D-10A (as alluded to in my "pitch up" thread). Its either nervous and jittery like on a caffeine high, or too lazy and hunts for altitude with 100+ foot excursions above or below target. And despite the fact that I have the larger SV-42 and the torque set to 100%, it sometimes cant hold altitude in a 180 degree turn.


Very anoying. As a contrast, the True Track in the -8 is absolutely rock solid.

[Tom Martin]

I used to have the same issue with my TruTrak/4500AFS system. I disconnected the static port on the unit and vented it directly to the cabin. The pulsing in smooth air when away. The only downside that I have experienced, in 10 years, is that the aircraft will bobble a bit if you quickly open an air/heat vent. This simple modification was done on the recommendation of someone else, so long ago that I can not remember all the circumstances but it has worked well since. It would be an easy thing to try and the smart lads in this crowd can then come up with a proper solution!

[flyenforfun]

I'll have to investigate this theory
Thanks

[MikeyDale]

Not sure if my issue is the same but on a recent trip with smooth air, my Dynon SV AP was pulsing some and it was annoying me. I wound up trimming up a couple of hits and it smoothed out.

[krw5927]

Exact same issue here, only once in a while, in smooth air.

Tore into the pushrods and linkages to see if there was any slop - none that I could find.

I figured it was just me. Maybe Dynon can look into this?