Trio Autopilot in Cessna 172

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My avionics guy started installing my Trio autopilot in the 172L this week. Servos went in quickly and easily. He's working on installing the control head but I told him to 'clean up' old wiring behind the panel while he's in there....didn't realize what a rats nest that was going to be....I think he's pulled about 10-15 lbs of old wiring and connectors so far. Since we're at it I have him installing a new Garmin audio panel and reconfiguring my avionics stack too. I will post a write-up on install and initial impressions once he's done. This is the first one he's installed but so far no trouble at all on the install. Curious to know of those that have the Trio, did you need to adjust the factory set gains or were they good to go out of the box?
 
I've installed a few of them in experimentals. Seems I never got gain settings that I was happy with. Somewhat acceptable gain settings, yes; happy with, no. It will likely perform much better in a 172 with huge control throws required for attitude changes. Pretty easy to adjust them in flight if you decide to play with it a bit.

I really like the trios ability to turn on pitch and roll servos independently. On approaches I frequently will leave the roll servo on and hand fly the pitch.
 
The Comanche I co-own has had a trio for just over a year now. I started flying it a couple months ago and while the vertical performance was solid, the horizontal tracking has been erratic with somewhat random hunting and over correction. We just had the gains adjusted this week and the partner who flew it after said it was much better so I'm hopeful to see improvement. It's fairly easy to use and plays well with our Garmin GTN650 and G5's.
 
My avionics guy started installing my Trio autopilot in the 172L this week. Servos went in quickly and easily. He's working on installing the control head but I told him to 'clean up' old wiring behind the panel while he's in there....didn't realize what a rats nest that was going to be....I think he's pulled about 10-15 lbs of old wiring and connectors so far. Since we're at it I have him installing a new Garmin audio panel and reconfiguring my avionics stack too. I will post a write-up on install and initial impressions once he's done. This is the first one he's installed but so far no trouble at all on the install. Curious to know of those that have the Trio, did you need to adjust the factory set gains or were they good to go out of the box?
how did the auto pilot work?
 
We just finished it Friday. I had a bunch of other work done while it was in there. I'll report back once we get some decent weather and I can try it out.
 
I have the Trio EZ auto pilot in my experimental. Tweaked the settings a bit but I find it to work very well now that it's sorted out ...
 
Have a buddy that has had issues with his.
According to him, the servos have plastic gears that didn't do well. Also had the over correction issues, but mostly in light turbulence.
They said servos with metal gears are coming.
 
Been waiting for quite some time for the auto pilot to be approved for the Cessna 150/152 airplanes.
 
Review and report:
The autopilot works pretty well straight away. At first it had some significant 'hunting' which was quickly remedied by some in-flight adjustment to the gains. The autopilot works as advertised. The 'buttonology' takes some getting used to so study the manuals before going flying.

One of the big things is that you gotta know where with airplane in trimmed and work with the autopilot on that. I shot 2 coupled approaches (in VMC) and the autopilot will fly it right down to the numbers if you let it. There will be a learning curve with adjusting the trim/power/flaps at the point where the autopilot captures the glide slope.

I think one more flight to tweak the gains and I'll have it dialed in nicely. Overall, I would highly recommend the Trio to anyone looking for a cost effective autopilot solution. Jeff at The STC Group was fantastic with helping in the set up. He answers the phone and knows the system very well and is great at explaining the details over the phone. Customer service gets a 10 out of 10.
 
My avionics guy started installing my Trio autopilot in the 172L this week. Servos went in quickly and easily. He's working on installing the control head but I told him to 'clean up' old wiring behind the panel while he's in there....didn't realize what a rats nest that was going to be....I think he's pulled about 10-15 lbs of old wiring and connectors so far. Since we're at it I have him installing a new Garmin audio panel and reconfiguring my avionics stack too. I will post a write-up on install and initial impressions once he's done. This is the first one he's installed but so far no trouble at all on the install. Curious to know of those that have the Trio, did you need to adjust the factory set gains or were they good to go out of the box?
Curious how it went. I’m going back and forth between the BK AeroCruze and the Trio. 172M with a GTN750 and dual G5’s. Have heard folks who love/hate either. Hope yours is doing well. How many hours on the install? Thanks
 
Curious how it went. I’m going back and forth between the BK AeroCruze and the Trio. 172M with a GTN750 and dual G5’s. Have heard folks who love/hate either. Hope yours is doing well. How many hours on the install? Thanks
I’ve got 25 hours on it and so far I’m really pleased with it. See my most recent post in this thread.
I’ve had fantastic support from Jeff @ STC group for any and all questions. In fact I would consider that to be the biggest selling factor over the lousy support that is typical with BK.

I gotta be honest though, if you’ve already made the investment of a 750 and dual G5s, I’d go with the Garmin autopilot since your 3/4 of the way there already. It’s a better unit altogether but typically people are scared away by the cost of the G5’s too, but in your case you’ve got that done already.
Overall I’m thrilled with the performance of my
Trio for relatively minimal investment
 
I’ve got 25 hours on it and so far I’m really pleased with it. See my most recent post in this thread.
I’ve had fantastic support from Jeff @ STC group for any and all questions. In fact I would consider that to be the biggest selling factor over the lousy support that is typical with BK.

I gotta be honest though, if you’ve already made the investment of a 750 and dual G5s, I’d go with the Garmin autopilot since your 3/4 of the way there already. It’s a better unit altogether but typically people are scared away by the cost of the G5’s too, but in your case you’ve got that done already.
Overall I’m thrilled with the performance of my
Trio for relatively minimal investment
Thanks. Yea, I know the GNC is a better AP, but am trying to match me need to the price. I have an STec20 that works fine, but no alt hold. I have two G'kids starting lessons in the plane and like the recover, 180 turn and bank correction features. I'm old :) I was taught by an ex AF flight instructor who was there the entire time and a task master. My G'daughter has been flying for six months and is on her third instructor and I have more hours than any of them. Different world and I think they need all the protection they can get. They will be a long way from worrying about approaches. Plus, been a few years, but I paid $60k for the plane...with STec, 750 and 180 hours on a zero time engine. Having trouble reconciling spending $20k on AP for a plane that I bought for $60k. Glad it is going well for you and hear the same about Jeff. He has been great with my questions. Thanks
 
I’ve got 25 hours on it and so far I’m really pleased with it. See my most recent post in this thread.
I’ve had fantastic support from Jeff @ STC group for any and all questions. In fact I would consider that to be the biggest selling factor over the lousy support that is typical with BK.

I gotta be honest though, if you’ve already made the investment of a 750 and dual G5s, I’d go with the Garmin autopilot since your 3/4 of the way there already. It’s a better unit altogether but typically people are scared away by the cost of the G5’s too, but in your case you’ve got that done already.
Overall I’m thrilled with the performance of my
Trio for relatively minimal investment
I agree with this statement if you already have panel full of Garmin.
My GFC500 worked perfectly from the first day it was installed with no adjustments ever.
After about 650 hrs my first servo went bad, now all three of my servos are -21 and have been replaced free of charge. That has been the only issue with it. I now have flown it 1400+ hrs so far. I don't want to get rid of my 172 because of the awesome Garmin panel in my plane that has perform flawless since 2018 when the 650 gps was first was put in.

It fly's so good that my 25000 hr buddy is have one installed in his arrow as I type this. I get to fly his plane pretty often so I will see how his does here soon.
I have never regretted spending the big bucks on the GFC500 for my 172. Mine was only the third install in a 172 that my shop did in spring 2019. Now they said they are putting one in every week at their shop when I was there a couple weeks ago dropping off my buddy's arrow.
 
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Thanks. Yea, I know the GNC is a better AP, but am trying to match me need to the price. I have an STec20 that works fine, but no alt hold. I have two G'kids starting lessons in the plane and like the recover, 180 turn and bank correction features. I'm old :) I was taught by an ex AF flight instructor who was there the entire time and a task master. My G'daughter has been flying for six months and is on her third instructor and I have more hours than any of them. Different world and I think they need all the protection they can get. They will be a long way from worrying about approaches. Plus, been a few years, but I paid $60k for the plane...with STec, 750 and 180 hours on a zero time engine. Having trouble reconciling spending $20k on AP for a plane that I bought for $60k. Glad it is going well for you and hear the same about Jeff. He has been great with my questions. Thanks
In 2018 I bought my 172 from a friend for 35K. At the time I thought I paid 5K more than I should have. It had a mostly all original panel. I promtly sent it over the avoinic shop for a GMA345, 650 gps, GNC 255 com/nav 2, indicator, GTX345, 2-G5s and all the other stuff it took to make it all work. The work was done in 10 days and I was flying it with zero issues. The installer mentioned how he liked working my plane because it was all original behind the panel which made the install easier.
4 months later I took it back for a GFC500 install which only took a another 10 days to install and it flew perfect from the start. That all was 58K into a 35K airplane. I kept it to myself as I was kind of embarrassed to spent that kind of money on it in late 2018 and early 2019.
Then in 2020 it got a 0 hr lycoming rebuilt engine. It was 30K all in with me doing the work. I have flown it 1400+ hrs since 2018.
2 Fridays ago I was at the avionic shop and Scott mentioned I could sell my 172 for 200K and fast because panel work is so expensive now with wait times close to a year to get the work done. So I am still above water on this deal so far. I never thought that would happen.
 
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I agree with this statement if you already have panel full of Garmin.
My GFC500 worked perfectly from the first day it was installed with no adjustments ever.
After about 650 hrs my first servo went bad, now all three of my servos are -21 and have been replaced free of charge. That has been the only issue with it. I now have flown it 1400+ hrs so far. I don't want to get rid of my 172 because of the awesome Garmin panel in my plane that has perform flawless since 2018 when the 650 gps was first was put in.

It fly's so good that my 25000 hr buddy is have one installed in his arrow as I type this. I get to fly his plane pretty often so I will see how his does here soon.
I have never regretted spending the big bucks on the GFC500 for my 172. Mine was only the third install in a 172 that my shop did in spring 2019. Now they said they are putting one in every week at their shop when I was there a couple weeks ago dropping off my buddy's arrow.
I finally got over the 550 cost…wife said, just do it. Then I got to the question of auto trim and it added another $5k. Just struggling with spending that much money on a 172 that I paid $60k for. I’m mostly VFR or very lite IFR. I have an STec20 for the lateral mode. Really just looking for alt hold. On a cost per hour, that’s pretty steep
 
hello all, anyone have a guess at the hours to install the GFC500? airplane is a C172, couple w a GPS175 WAAS. Panel is all analog, indicator is a Collins ind351, and DG w a heading bug. Installed an Approach Fast Stack coupling system for all the avionics... Guesses appreciated. THANKS
 
hello all, anyone have a guess at the hours to install the GFC500? airplane is a C172, couple w a GPS175 WAAS. Panel is all analog, indicator is a Collins ind351, and DG w a heading bug. Installed an Approach Fast Stack coupling system for all the avionics... Guesses appreciated. THANKS

You need to install a G5 (I would go with 2; attitude and HSI) and I assume 3 servos, no need for yaw damper, I would guess 60-75 hours. No idea how much fast stack helps.
 
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