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Anyone installed a Trio A/P yet?

Tom3holer

Registered User
Cape Cod
Hi,
I have been following the Trio A/P certification and it is now STC'd for the 172, 182, 180, 185.
I would like to talk with someone that has installed one and get there feelings on installation and operation before I make the commitment.
Has anyone here installed on or know of someone that has?

Tanks,
Tom
 
I looked at them also but it seemed that Trio along with the STC group was ahead on getting certified so was waiting to see how they work out.
Please let me know how it works out.
Tom
 
I installed the TruTrak AP (Gemini controller version, non-certified; it's the one with a flight instrument style display) in my Northstar, a Supercub lookalike.

[SKIP TO PARAGRAPH THAT STARTS "BOTTOM LINE" if you aren't interested in details!]
Installation of the pitch servo on bottom of floorboard under pilot seat was reasonably straightforward. The cable on the servo wraps about three turns around a capstan and the cable then attaches to the elevator control cable with aluminum clamping bars.

The roll servo was more of a challenge; I couldn't find a straight run of aileron control cable where I could mount the servo. Final solution was to mount it facing forward under the passenger seat with the capstan just ahead of the passenger seat forward bar. The cable on the capstan then went outboard on both sides and around pulleys that I installed just under that seat bar and attached to a swiveling bracket I built that attached to the rear seat control column. So the rotary motion of the servo translates into pulling right/left on the control column.

There was a fair bit of wiring and soldering to the three connectors (two servos and the controller); only solder-tail connectors were provided. If I were to do it again, I'd buy connectors with individual crimp pins (B&C).

The pitch servo worked great from the start. The roll servo never did. I spent A LOT of time ringing out my wiring, removing and reinstalling the roll servo, and even sent it back to TruTrak (they said it checked out fine!). Lots of time on phone with a technician at TruTrak. Finally he suggested attaching the roll servo connector to the pitch servo and voila! The roll inputs to the pitch servo drove it great in both directions. So it seemed obvious that the roll servo wasn't working; I sent it back down there and again it checked out fine.

Finally I took the plane down to the TruTrak factory in Arkansas (foul weather). The problem turned out to be inside the controller and required some bench work to fix it while I waited. Both servos were working great now! I discovered that I had a baud rate mismatch between my Garmin 496 and the TruTrak; when that was resolved, the AP worked exactly as advertised. I still have to tweak a couple of parameters because it overcorrects when tracking to the course set in the Garmin, but that can be done in the air easily. The pitch servo and altitude modes (hold, climb, descend) work great as they always have.

BOTTOM LINE: I like the TruTrak, and the people at the factory were very responsive and helpful. Maybe the controller problem should have been found and fixed before it was shipped to me, but maybe a solder bridge I discovered in my rework had damaged it. Whatever, TruTrak is a known entity for me now, and I plan to put one in my 180 when they get their STC. I like that the 180 version doesn't use control cable attachments; it directly drives bellcranks using push/pull tubes.
 
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Thanks Lytlej,

Than was very helpful. They have changed as you said to push/pull tube and a clamp around the yoke.
I do hope someone chimes in here soon with a 180 or 185 and a review.
Tom
 
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TruTrak will have a servo attached to the left aileron bellcrank and the pitch servo will be driven off the elevator bell crank in the rear fuselage (near tail pull handles) on the 180-185. No bridle cables to slip. Not enough room on the yoke just aft of the firewall like the 172 STC.
On my Smith Cub the aileron servo ran off a bellcrank under the pilots seat attached to the outer torque tube. Ran it for over 1500 hrs. Never a problem. TruTraks will water your eyes the way they handle turbulence. They are always my first choice for autopilots. I know nothing about Trio. Worth the wait (a few weeks perhaps) IMHO.
Lou
 
Thanks Lou,
That would be nice if it were only a few weeks but there seems to always be delays. Trio's 185 stc went from Oct to just a few weeks ago, I believe, when they began shipping the install kits.
I have looked at both and am waiting for the 180/185 installation manual to come out and see how that looks.
I wasn't really crazy about the clamp on the yoke idea, glad to hear its not that way.
Tom
 
Lou, does the upcoming TruTrak STC specify left aileron bellcrank, or could I install it in the right wing? I think I asked that question of Trio and they said either side. I guess the motion would need to be reversed on the other side; TruTrak's parameter set allows the reversal to be done without changing wiring, at least for the experimental version and only on the pitch servo. Or maybe a certified version won't have so many configuration parameters for the user?
 
Suggest you call TruTrak and speak to Zach Williamson. Tell him I said to call about the aileron servo install. My understanding is the certified Cessna autopilots were all put in the left wing. Give them a day or so to decompress from SnF. My understanding is they will ship the install kits very shortly after STC approval. I know they have been gearing up for some time now.
Lou1
 
Lou,
I thought they were in the right wing but not positive. I will give them a call in a few days. Do you have any idea when the install manual might be available?
I do like the looks of their servos as compared to Trio. I called Trio and asked it they were brushless motors and they said no they buy them from Japan.
By the way that is a lovely daughter you have in your avitar.
Tom
 
Thanks Tom
I’ll tell Kathy what you said. She has a birthday coming up. It should help!
I could be wrong on the certified wing thing. Ask about the install manual and pictures when you talk to Zach.

Lou
 
....I wasn't really crazy about the clamp on the yoke idea, glad to hear its not that way. Tom

I assume you're talking about the roll servo mounting on the control column / yoke that comes up behind the panel.
I'm curious why you don't like this arrangement?
A buddy of mine has a Bushmaster type homebuilt and he has a single-axis TruTrak A/P which mounts this way,
and it seems real slick to me-- easy to install and easy to get at if it needs attention.
 
I bought the Install kit at Sun N Fun last week. They had a show special. I had a long discussion with Mark from The STC Group. There is a big install disparity between what most of the shops quoted me (50 hours) and what STC Group claims (30 hours). Also, It requires a GPS input. You can use a potable, but if you want VNAV you have to use a WAAS panel mount. However it is not approach certified. They said they would ship the install kit in a few weeks because they were updating the installation manual. I think they're using feedback from installers. Despite all that I'm really looking forward to this. I could never stomach paying $20k for an antique STEC.
 
The pitch servo attaches to the yoke in the early version of the Trutrack. The latest version is in the tail and attaches to the horizontal stab in the 172.
Just got off the phone with Trutrack after a 30+ minute conversation and put my name on the list for their unit and install kit for my 185.
I had several questions that were answered to my satisfaction in depth which impresses me.
In reality I think both will do very well for 90% of the flying I do for half the price.
 
Tom
Did Zach say why they use the left aileron for the roll servo? Glad you got detailed answers.
They are real pros. Lots of history.
Lou
 
Lou,
No he did not. Some of the install manuals I looked at earlier use the right wing but he did say they use the left wing on the 180/185. Also the newer setup for the 172's use a tail mounted pitch servo now too.
I was surprised to learn that they mount the pitch servo on the belly skin in the tail. I asked if there was a doubler used and he said no but the mount was rather long.
I asked about the optional inspection hole for the jackscrews in that area and he was very aware and says it does not interfere with it.
Overall quite impressed.
Tom
 
Tom
i was concerned the rod connecting the servo to the elevator bellcrank would interfere with the tail pull handles. Was told the 180 they used in R&D had pull handles so no interference.
Did they give you any updates on when the STC would be released?
 
Good point I forgot about the pull handles which I also have.
I asked him when the install manual would be ready and he said he was actually writing it and should be a week to 10 days. The STC should be about a month.
 
Just got the Trio a/p installed. Only had time for a short test flight but it's slick. Did an LPV approach (VFR) and was impressed with the smoothness. Needles dead centered all the way down.
Can't beat it for the price/features.
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C180J. $3,400 for the autopilot, $2,700 for install kit/STC, and 50 hours for the install. Hooked up to a GTN650 gives VNAV capability. About half the cost of an old STEC.
 
I too am thinking about a C180J install.

How much drag on the cables, or extra control force is needed when the autopilot is not engaged?

Would I be able to tell the difference between before install and after?
 
I haven’t noticed any difference in control feel.
It has a nice function called PCS, pilot controlled steering. With servos engaged, you push and hold the yoke disc button, put the plane in the attitude/ bank you want, release the button and it holds that position.
Here’s the elev servo, mounted fwd of the inpection port.

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Did it indeed take 50hrs to install?
Is the 2x4 part of the installation? Just kidding.
Were you involved in the installation? This is my choice for an AP in my 73 185. Any comments on the installation?

Thanks,
Tom
Cape Cod
 
Lou
Bob at Aircraft Specialties 182 was used for testing.
Bob said: Not sure on most, but Zack told me he wanted to put in the right wing but for some reason put it in the left wing.
It works great .
 
TruTrak put their 172 servo in the rt wing but moved it to the left wing in the 180 series.
Lou
 
It has been a while and thought I'd post an update.

I did decide to go with the Trio for several reasons the most obvious is the fact that TruTrak still does not have a STC for the 180/185.

There were a couple of other issues that were also considerations. The TruTrak does not offer Airspeed control was a biggie.
In a climb and descent if using V/S as pitch control one would be having to trim frequently whereas A/S trimming should be minimal.
I liked the idea of an integrated on/off switch on the face of the instrument also.
Talked with the owner of Trio as well as the head of the STC group that holds the STC several times and both were very informative and helpful.

The plan is to do the install in Dec when she is in for the annual and will post the progress.

Tom
 
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