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Anyone install roll and pitch autopilot servos? Which system? curious if anyone has pics to show how they were connected and were located. I see that Dynon has installation trays for Sonex. Perhaps it includes instruction showing location and installation…? Steve

sjakulski wrote:Anyone install roll and pitch autopilot servos? Which system? curious if anyone has pics to show how they were connected and were located. I see that Dynon has installation trays for Sonex. Perhaps it includes instruction showing location and installation…? Steve

Yes, several people have. Use that great search function on this site to read previous posts.

XenosN42 wrote:

sjakulski wrote:Anyone install roll and pitch autopilot servos? Which system? curious if anyone has pics to show how they were connected and were located. I see that Dynon has installation trays for Sonex. Perhaps it includes instruction showing location and installation…? Steve

Yes, several people have. Use that great search function on this site to read previous posts.

Did. Search function not so hot…

GordonTurner wrote:

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9C2BC81C-C455-43E7-8D45-DADCF24158BD.jpeg

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Thanks for the pics. Looks like the Waiex mounting/configuration is different than the B model center stick design though. The servos in the B will both go under the seat…I believe.

sjakulski wrote:Anyone install roll and pitch autopilot servos? Which system? curious if anyone has pics to show how they were connected and were located. I see that Dynon has installation trays for Sonex. Perhaps it includes instruction showing location and installation…? Steve

Hi Steve,

I installed a Trio EZ Pilot Autopilot. http://www.trioavionics.com/ez_pilot.htm

It has a lot of great functions when connected to a GPS but is a single axis unit. I mounted the roll control servo under the passenger seat and connected it to my center stick. I viewed several videos on the Tube showing installs of the servos. A few points to keep in mind:

1) Mounting under the seat gives you easy access to the unit and its associated hardware for inspection and service during condition inspection or any other time is may be needed. It is possible to mount both the roll and pitch servos under the seat pan. If I understand correctly the downside of this with the B model is that the seat pan is riveted in place so access to anything under the seat will be very difficult unless some other provision is made.

2) In watching the videos I'll link below (none are mine) you will see that it is of utmost importance that the flight control stops on the stick are engaged before the stops on the servo. As you will see in one of the videos below it was necessary to lengthen the servo arm to accomplish this. The servo I used allows a longer arm (specifications are in the instructions for the unit) to a small extent if needed.

3) It is imperative that no over center condition can occur. If that were to happen the stick would lock into place and you would lose control of the aircraft.

I trust you are already aware of these cautions but anyone considering attaching anything to flight controls should keep these in mind.

https://www.youtube.com/watch?v=Xifmypezxfc
https://www.youtube.com/watch?v=6UzjnIG7_Jo
https://www.youtube.com/watch?v=32xp8w32el8

Dunno if this helps ...

Dale
N319WF

The video’s are not of the Waiex-B design, unfortunately. The center stick design is completely different for servo attachments. But, thank you. I have already cut access panels in the seat pan (and top of the glareshield). Dynon supposedly has servo trays for Sonex (as well as RV’s), but I’m still awaiting word back from them if they are for the center stick B models or only for prior models… Steve

I installed the Dynon servos in my Waiex B. If I can find pics I'll post them, but I'm not sure I have any. The install kit that Dynon had at the time was for the legacy, not the B. But they were good enough to work with slight fabrication or modification. I installed the roll servo under the right seat just aft of the spar and made a pushrod with Heim joint ends that attached to the servo and the lower control stick assembly. Make sure it clears everything at the full range of motion.
Access is through 2 inspection covers in the right-side seat pan.

The pitch servo was also mounted under the right seat with a shorter pushrod and Heim joints, but more aft and closer to the center. The servo arm fit through one of the seat rib lightening holes and I attached it to the forward elevator pushrod. (The one that attaches to the stick).

Most important, I think, is to make sure that you do not mount the servos directly to the bottom fuselage skin. Make a flat tray with aluminum and a short 90-degree stiffener bent onto one edge, at least 032, maybe thicker, between the servo and the skin. The fuselage skin is not stiff enough and the servos should be mounted on something more substantial.

If you look at the Dynon Sonex install instructions, they show this concept. I fabricated my own because the B has straight sides and the Legacy Dynon mount has angled sides. Dynon made the roll mount to fit the angled fuselage of the Legacy Sonex.

pappas wrote:I installed the Dynon servos in my Waiex B. If I can find pics I'll post them, but I'm not sure I have any. The install kit that Dynon had at the time was for the legacy, not the B. But they were good enough to work with slight fabrication or modification. I installed the roll servo under the right seat just aft of the spar and made a pushrod with Heim joint ends that attached to the servo and the lower control stick assembly. Make sure it clears everything at the full range of motion.
Access is through 2 inspection covers in the right-side seat pan.

The pitch servo was also mounted under the right seat with a shorter pushrod and Heim joints, but more aft and closer to the center. The servo arm fit through one of the seat rib lightening holes and I attached it to the forward elevator pushrod. (The one that attaches to the stick).

Most important, I think, is to make sure that you do not mount the servos directly to the bottom fuselage skin. Make a flat tray with aluminum and a short 90-degree stiffener bent onto one edge, at least 032, maybe thicker, between the servo and the skin. The fuselage skin is not stiff enough and the servos should be mounted on something more substantial.

If you look at the Dynon Sonex install instructions, they show this concept. I fabricated my own because the B has straight sides and the Legacy Dynon mount has angled sides. Dynon made the roll mount to fit the angled fuselage of the Legacy Sonex.

Thanks Lou. Yes, Dynon did get back to me on the B model question, Their servo trays were designed for the legacy configuration and I was prompted to ask this builder site about using/retrofitting. So, your response was good timing. :)

I used the same locations as Gordon. Only difference is I used the left wing and attached it to the spar and attached the actuating arm to the bell crank. We both appeared to have used a spot behind the seats for the pitch servo. Drilled an extra hole where the two control rods meet and attached the arm to that. These are with Garmin servos and I used the universal mounting kits.