VAF Forums

VAF Forums (
-   Autopilots (
-   -   San Jose RV-8 Garmin Autopilot Install (

49erMike 05-22-2021 02:30 PM

San Jose RV-8 Garmin Autopilot Install
We have a flying RV-8A with Garmin 430W and (non touch) G3X, and would like to install a Garmin Autopilot. Interested in talking with anyone who has done similar install, as well as recommendation for Northern California shop or person to potentially assist with wiring/electrical or possibly entire installation. Thanks!

Mike S 05-22-2021 05:12 PM

Welcome to VAF
Mike, welcome aboard the good ship VAF:D

Couple of recommendations for you.

Randy Thorne

Lars Pedersen

rapid_ascent 05-22-2021 09:29 PM

Mike, I donít think this install is that difficult if you decide to do it yourself. There is a little bit of work mounting the servo brackets and intercepting the CAN wiring for the addition of the servos.

49erMike 06-08-2021 10:03 AM

Appreciate the responses, leads, and thoughts. We are pulling the trigger on the install; Iím comfortable with the mechanical aspects of the installation - for several reasons will likely get some help on the wiring/electrical and configuration side. Iíll post results when done or anything noteworthy comes up.

rapid_ascent 06-08-2021 12:01 PM


I sent you a PM.

49erMike 01-12-2022 07:03 PM

RV-8 Garmin Autopilot Install Complete
Apologies for the tardy update on this, but our Garmin autopilot is now installed, calibrated, and flight tested. We are very happy with it. Our RV-8 already had a Garmin 430W and legacy (non touch) GDU 375 PFD/MFD, which made the install easier. We purchased two GSA 28 servos, a GMC 507 Control Unit, and RV-8 servo mounting kits for the pitch and roll servos from Garmin. Installation went quite smoothly; the roll servo mount kit is basically a bolt-on replacement for the existing aileron bellcrank mount. The installation of the pitch servo mount is more involved, as it requires drilling out 10 rivets to remove the old bellcrank brackets, match drilling the rivet holes into the new servo brackets, and riveting the new brackets into place. I was able to get a bucking bar underneath, which allowed me to drive rather than squeeze the rivets. For a number of reasons (not the least of which is we have Nik Nickravesh and his crew at Nice Air on our home field at KRHV in San Jose), we decided to let them do the wiring and that worked out well. We have the Ray Allen electric pitch trim, which is fully compatible, so the autopilot will automatically re-trim during climbs, descents, power changes, etc., and we also installed autopilot disconnect and TOGA (take-off / go-around) buttons on the control stick. We found several glitches in the Garmin documentation, but phone support from the Garmin experimental folks was top notch. The system performs better than expected, and we had pretty high expectations going in. It holds altitude in cruise WAY better than me, with minimal altitude loss rolling into turns and gain when rolling out of turns (typically 30-40 feet), which are quickly recovered. It is rock solid on approaches, including vertical descents on LPV and ILS approaches. Total hardware expenditure was $3,300 for the control unit, two servos and servo mounting kits, electrical connector kits for servos and control unit, tax, and shipping. I am happy to answer any questions and have photos I can share with anyone interested in this upgrade.

polkaking27 01-16-2022 09:54 PM

Hey Mike,

I'm looking at adding the GSA 28 servos to my rv-8. What are your thoughts on the 507 control head vs controlling it on the G3x. I was thinking of just using my g3x touch but am not against adding the control head if there is good reason.
Also, I'd love to see any pictures (both servos would be awesome but I'm particularly interested in the pitch servo and the work required) and get any advice on how to do the install. I don't have rivet gun, does the install allow for pulled rivets for the pitch servo? Also, where do I get the instructions for install? Do they come with rv-8 install kits or are they published by Garmin?

Thanks so much. I will PM'd you this same message along with my email incase you check that sooner.


49erMike 01-26-2022 05:19 PM

507 Control Unit
You absolutely want to get the 507 control unit - if you already have a G3 the 507 will be the most expensive component but worth every penny. Iím still learning to use the autopilot (completed practice ILS and LPV last weekend) and canít imagine trying to control it any other way. The separate twist knobs for setting heading and altitude bugs, combined with the thumb wheel to set airspeed or VSI rates during climbs and descents really make this a must have in my opinion. I just saw your PM and will respond with some photosÖ

All times are GMT -6. The time now is 07:38 AM.