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Pirep on Trutrak Gemini Autopilot

Larryskydives

Active Member
Thought I would do a pirep on purchase and installation of Trutrak Gemini Autopilot. I have a RV6 purchased from the original builder. No autopilot installed, so starting from scratch. In a search for and AP, I looked at various models and mfg. in reviewing online information, I liked the installations of the servos in the RV6's by Trutrak. Not wanting to cut any new holes, the I liked the idea of the Gemini control head to replace my artificial horizon. This is not to say the Trutrak is any better or worse than any other mfg, this is my experience with this unit only.

1 - While looking I had several conversations with Zack and Lucas at Trutrak. They answered all of my questions and gave clear answers and the website had very good information and downloads for manuals and installation drawings and info. Afterwards found the operating manuals to be an older version, but installation drawings were still current for the pitch and roll servos as well as the auto trim module.

2 - Upon making the decision to purchase the Gemini unit, I found Aircraft Spruce to have a discounted price. I spoke with Trutrak about meeting that price. They would not meet the price but said that no matter where I bought it from they would back it as if I purchased it directly from Trutrak. I mentioned that I was looking at buying parts and pieces from SteinAir to build my harnesses. Was told that SteinAir was a dealer. Called Steinair and spoke with them and although they discounted the price, it was not as low as Aircraft Spruce. To make up the difference, they said they would discount the harnesses if I would buy the premade harnesses. That is what I did. Purchased from SteinAir the Gemini and harnesses. I received the harnesses in a weeks time. And it was three weeks to receive the Gemini AP Package. Time frame was acceptable and packaging was very good.

3 - Preparing for installation, I got a lot of good information from Steinair's website. Great videos on working with the harnesses and different wire connectors and connecting procedures. Wound up buying some wiring tools. Dsub crimpers and pins mainly

4 - Installation of the unit. Roll servo installation went well following the installation drawings. Pitch servo installation was little more time consuming. Using the dimensions from the installation drawings, looked like it was going to be as easy as the roll servo. However, guess building differences between builders, a little modification was needed. Mainly, installation was on the opposite side of the bellcrank for the pushrod and I had to shim the servo mounting with a couple of washers and longer bolts to offset the servo and allow proper clearance for the pushrod. Pitot and Static line mods were straight forward. Removing the artificial horizon, I had blocked off the vacuum lines where they connected to the instrument. Still using vacuum for the DG. Running of the harnesses were fairly straight forward. Used 5 amp toggle switch circuit breaker to control the autopilot and trim module. Connected the power wire to the battery side of the battery solenoid. This so that should I have an electrical issue where I needed to turn the master off, I would still have the control head giving me altitude and speed as well as vsi functions. Should there and electrical issue with the AP, I can isolate and turn it off if necessary. AP level switch and autotrim status were located in view and easy access by both pilot and passenger.

5 - Only issue in installation was an ambiguous statement on the wiring for the autotrim. States - Do not connect to aircraft power. This was for the No. 7 pin going to the status light. Lucas informed me that some people had tried to wire it directly to power without using the led status light. I did install the status light and on initial ground setup, set to where it flashed approx. 1 time per second. This was recommended by Lucas.

6 - GPS Interface. While I have KX135A, I am driving the Gemini with a Garmin Aera 510. Being a commercial pilot and flying various aircraft, I use my 510 in various aircraft using a Ram Suction Cup Mount. I purchased a second mount setup and a power cord that had the "blue" wire to interface with the Gemini. This mount is now dedicated to the RV6 and I now just clip in the 510 when flying the RV6. Interfacing through the setup menu went easily.

7 - On the ground setup the Roll Servo was operating reversed. This addressed in the manual and reversed pins 4 and 5 and checked unit again and roll servo was correct. Set parameters to recommended parameter for the RV6.

8 - Test flight went well. Hand flew to 2500 ft and turned on the AP. Heading hold worked well, GPS tracking for flight was stable. Altitude hold and vertical speed worked as expected. Put the aircraft in a climbing right turn with a 30 degree bank and pressed the AP Level button. Aircraft stopped the turn, held altitude and leveled the wings. Test flight was a success.

9 - Thoughts - Control knob is a push, turn, toggle all in one switch. A little odd at first until you realize what each push turn or toggle does in operating of the AP. After 2 flights it much easier to use knowing how to use the right push turn toggle combination.

10 - All in all, very pleased with the unit. Wish I put one in sooner. I recommend the Gemini, especially if you have a steam gauge panel and don't want to cut another hole.
 
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Larry, thanks for the report

I installed a Vizion 385 in my -6A about 18 mos. ago, but I would like to upgrade the control unit to the Gemini, for the display ---- I understand it is just "plug and play" exchange, and I do have the 3.125 hole available.

My only concern is the "push, turn, and toggle" single control. I have read others that were not happy with that one feature. I will be interested as you build experience with the control, especially how it works in turbulence.

By the way, I love my RNAV coupled approaches with the Vizion 385 working with my Garmin 650. Wonderful magic!

Ron
 
I replaced my ADI II with the gemini and installed the pitch servo (thanks Jay Pratt for helping!!). Very happy with the unit and the single joystick is just fine. it took a little time to adjust to the single joystick and turbulence can be tricky but its an awesome tool. the wing leveler can be a life saver!
support has been excellent and the unit is uncomplicated and well built.
 
By the way, I love my RNAV coupled approaches with the Vizion 385 working with my Garmin 650. Wonderful magic!

Ron

Coupled approaches? My Sorcerer/G-900X oesn't ddo coupled approaces. Is this something new?

-Marc
 
Coupled approaches? My Sorcerer/G-900X oesn't ddo coupled approaces. Is this something new?

-Marc

If your Sorcerer isn't performing coupled approaches (GPS AND ILS) from your G900X, then something is amiss with the wiring or the interface setup on the G900X. That combo is capable of both. Send me an email with some more details and we'll see if we can get everything working like it should. [email protected]
 
Hello Larryskydives.....I have purchased the TT gemini AP and also fly a 6. Going to install in March sometime. I was wondering about why you had to mount the pitch servo on the opposite side of the bell crank. (i haven't even looked at the job yet) Also I wondered why your roll servo operated in the opposite direction initially. Were the initial wiring instructions in the manual not correct?
 
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