Aileron Servo placement

[U2fletch]

Right wing is a good place to locate aileron autopilot servo, so I would like to see any pics of their installation. I have a convenient spot in mind, but a clean attachment to the bellcrank is eluding me. Would be nice to use the same hole in the arm as the pushrod, but there is a clearance issue with the support tube.

[huntaero]

This is how i mounted my A/P servo in the RH wing
IMG_0005.jpg IMG_0006.jpg IMG_0007.jpg IMG_0010.jpg

[U2fletch]

Brilliant! I initially dismissed the capstan idea because I thought I needed to get to both cables. Nope, it’s a closed loop you just need to grab one.

[rkennell]

IMG_5703.jpg IMG_5664.jpgIMG_5667.jpg
I mounted mine under the copilot seat. It is a very accessible place and a good place to tie into the Skyveiw network.

[FFTravism]

I know Virgil is working on a adapter plate to mount the servos. Not sure the status as I am not to that point.
Travis

[U2fletch]

Here are some pics that Virgil sent me.. Servo2_resized.jpg Servo4_resized.jpg Servo3_resized.jpg Servo1_resized.jpg

[500AGL]

This is the pitch and yaw servo locations, at the last fuselage station. Pitch is a pushrod to the elevator bellcrank and Yaw is bridle cables to each rudder cable.

[Dpearson]

Thanks for sharing the photos! I'm planning to follow this general approach on my BH4 build. A couple of questions:
1. Do you know material thickness and spec for the mounting plate? 2024-T3 or ???
2. I was planning on a capstan + pulley approach for connecting the yaw servo to the rudder cables, using one bridle cable with a ball in the center and bridle clamps (Vans CS-00022) to connect the bridle cable to the rudder cables. What I see here is one long arm, which I imagine is long enough to line up the bridle cables at each end with the rudder cables as they exit the fairleads. I think this is quite elegant, but I'm wondering if the GSA28 servo will have enough torque to overcome the air loads on the rudder in my application. The RV-10/14 installation is similar, with a total arm length of about 4.75" according to https://vansairforce.net/threads/van...0/post-1258276 . In my BH4, the arm would be 9" long to line up with the rudder cables. The max torque spec of the GSA28 Servo is 60 in-lb (from the G3X Install manual), yielding 60/4.5=13.3 lb maximum "pull" on whatever rudder cable needs pulling. The rudder pedals give a ~2:1 advantage, so 13.3 lb of cable force is equivalent to 6.7 lb of pedal force. Does anyone know if this is sufficient for actual control surface loads the autopilot will encounter in flight?

[U2fletch]

Here is a pic of my final installation of the aileron servo. 20250705_122130_resized.jpg 20250705_121944_resized.jpg

I used .062" plate that I had sitting around. Probably 6061. With the flanges and riveting to the ribs, it is very strong.

[U2fletch]

20250730_173849_resized.jpg 20250802_115323_resized.jpg

Here are pics of the rudder and elevator servo setup using the capstan. I machined my own blocks for the cable attachment.

[Have-Purple]

Are there any updates on the official bearhawk servo install?

U2fletch Any chance you will publish drawings or more details on your brackets?