Yaw Damper RV10

[rjones560]

The Dynon yaw damper on my RV10 is a little weak to keep the ball centered in all normal pitch and airspeed combinations. I have a fixed trim tab and have adjusted it a few times, but I can’t get it to fly ball centered at both low speed in a climb and high speed in a descent because it does not have enough torque to do so with the long tiller arm. I was wondering if anyone has tried using a capstan servo. I was also wondering if the capstan drive can be bolted on to my existing servo. The capstan pulley would have a shorter arm and that would increase torque considerably.

Has anyone tried this and how did it work?

 

[DBRV10]

I have done a few including my own RV10.They work fine.

Set your fixed tab to give you a near neutral ball in level flight. Then set the following settings.

Torque 100%
Low speed sensitivity 3
High speed sensitivity 2
Rudder gain 2.5
Rudder rate 0.015
AY Gain 0.900

 

[rjones560]

I converted my yaw damper to a capstan drive on my RV10. It works perfectly now and keeps the ball centered from a Vx full power climb to a high speed descent. With the capstan drive the same servo has about twice the torque because the arm it is pulling on is half as long. Another advantage is that I can crawl by it a lot easier to get to the back of the tail cone.
To mount the servo with a capstan drive on it you will need to remove the cable guard as it won’t come close to fitting on the Van’s mount with it installed. You will also have to file back the ends of the braces on the bottom of the mount about 1/4 inch to have clearance for the capstan drive. If you are careful the ends of the braces will act as a cable guard to keep the cable on the capstan. I clamped the capstan cables on to the rudder cables about 12” aft of the drive. That is where the plane of the capstan intersects the rudder cables. I crimped a copper stopper on the cable ends to make it easier to get the capstan cables tight. I noticed that the rudder moves back and forth with more resistance when the aircraft is parked. I still put the rudder lock in when I park it outside, but the servo provides enough drag to keep the rudder from slamming to the stop in anything but the strongest winds.

 

[DaveRV10]

I am the owner of axRV10 in South Africa and would like to fit s yaw damper into thisx aircraft .Still has the older model Trutrak autopilot and is looking at any suggestion please.Do i have to replace the auto pilot or can i fit a system to this auto pilot
.

 

[rjones560]

I am not aware of a yaw damper available for TruTrack auto pilots. The Dynon autopilot is built into their EFIS. The servos are hooked up to the network so the autopilot can be controlled from any EFIS installed. I have 3 EFIS screens in my RV10 and they all can control the servos through the network. This system is totally integrated and one part can not work without the other. The whole avionics industry is moving in this direction.
Bendix bought TruTrack a while ago so they must be planning to either integrate them into their product, or they wanted some technology under patent that they had.

 

[Janekom]

I am the owner of axRV10 in South Africa and would like to fit s yaw damper into thisx aircraft .Still has the older model Trutrak autopilot and is looking at any suggestion please.Do i have to replace the auto pilot or can i fit a system to this auto pilot
.

It will not work Dave. You will have to upgrade at some stage

 

[KenLeonard]

Is the yaw dampener anything other than just a third servo?
I have aileron and elevator servos installed but the Searey is so rudder centric that without a rudder servo, the aileron servo is pretty useless. I get that it is wired separately and has its own disconnect and c/b. How does the system “know” it is a yaw dampener servo when it is just plugged into the network? I presume I will be able to identify it in the system setup.

 

[rjones560]

You identify it during setup. On my RV10 I replaced the tiller arm with a capstan drive. That gave it more torque. The ADAHARS drives it. It is very sensitive and locks the ball in the cage during turbulence and climbs and descents. I love it.