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Tru trak vs garmin vs GRT?

T

Turbo69bird

Well Known Member
I?m looking to upgrade my auto pilot. Looking for thoughts on all the above pluses and minuses to each especially from those who have changed from one to the other or flown behind multiples.
Thanks for any input.
 
Any reason you left out Trio? I wanted an autopilot that could function following a complete EFIS failure. I chose Trio over TruTrak because I prefer servos with a slip-clutch over a shear pin, I wanted the servos out of the loop when not using the autopilot, and I like the larger display(which means less multiplexing of controls). In my -10 I normally control the Trio with my GRT Hx. It flies the plane like it?s on rails. I have the autotrim option: I can start an ILS or LPV approach at 130 knots; smoothly reduce power and/or add flaps until down to 75 knots; disconnect just prior to the flare, and the plane is in perfect trim. Also, I can use the autopilot trim manually, when the servos are disconnected. You can program the trim speed to run slower when you?re going faster.
 
Turbo69bird said:
I?m looking to upgrade my auto pilot. Looking for thoughts on all the above pluses and minuses to each especially from those who have changed from one to the other or flown behind multiples.
Thanks for any input.
Click to expand...

It's not quite that simple any more. You didn't mention if you have steam gauges or a particular vendor's EFIS installed.

With most of the modern EFIS, you will need to purchase your servos from the same vendor. Servos typically don't not integrate across vendor boundaries. Additionally most of the EFIS vendors don't require an AP head anymore. Some will support integration with other AP head vendors, but the functionality may not be the same as using the vendor's proprietary AP solution.

While I used to be solidly in the same camp as Bob wanting a separate AP head for redundancy (I currently have a Trutrak Vizion), I've probably swung my thinking to that I'm sitting on the fence. Especially when you look at technology like Dynon's SV-Network that is available on both Dynon and AFS EFIS. The SV-Network does give you the available to switch SV-Network connected devices from your PFD to MFD should an EFIS ever fail. I'm not familiar enough with other vendor's products to comment if they have similar technology available in their products.

I have AFS EFIS's. There are a couple functions that I can't get on the Trutrak Vizion that are available on the AFS EFIS/Dynon servo combination. But the differences aren't significant enough that I'm eager to swap out the servos yet.

If you look at the current products from AFS, Dynon, Garmin, and GRT, they each sell their own proprietary servos. For those of us that just use our IFR skills to pop up on top and then back down, I don't see a need for an external AP head anymore. Previous generations of each of these vendors EFIS may require the use of an external AP head.
 
Garmin Autopilot

I upgraded the Doll to glass in 2011 with the non-touch G3X. Garmin did not make an autopilot so they partnered with Trutrak which made the GX pilot to work seamlessly with the Garmin G3X. The system worked well, bit I found the autopilot would "hunt" in level flight unless the aircraft was in perfect trim. The step servos could have been much smoother.

In 2017, I upgraded the non-touch EFIS GDU370's to the Portrait Touch GDU470 G3X screens and the new Garmin GSA-28 "Smart" servos. When disengaged the servos have no load on the flight control system. When engaged the servos auto-trim with pilot programable variable speed sensitivity, and provide envelop protection. The first time I engaged the autopilot I noticed smoothness like the Boeing 777 I flew for AA.

The autopilot can be controlled from the EFIS panel or a GMC 305 or 307 or 507 autopilot control head which is well organized, and makes autopilot functions a breeze! If you have a G-5 standby EFIS, the autopilot will continue to operate using the independent G-5 with complete main panel failure. The G-5 has a 4 hour standby battery backup.

Two G-5's, two GSA-28 servos and a GMC autopilot control head and you have a complete low cost EFIS/HSI system. Add a navigator SL-30 or GNS or GTN etc. and you have a complete system.
 
Good Morning Turbo,

Danny has an excellent review of the Garmin autopilot above. If you get a chance to test-fly with the Garmin solution I think you will find it an absolute joy to fly with!

Without knowing how your aircraft is currently equipped, I just wanted to make a note that you do not need a fully equipped G3X EFIS to take advantage of the Garmin autopilot solution. To have a fully functioning standalone autopilot system you will need a single G5, GMC 507, along with the GSA 28 servos (up to 3).

As always if you have any additional questions feel free to reach out to us at the information listed below!

Best Regards,
Brad
 
Adding a photo of a basic G5 system with autopilot.

The autopilot can be coupled to any of our portable GPS units to follow a flight plan or direct-to with an RS-232 connection.

Even without a navigator, you can push the TRK button and use the HDG/TRK knob to steer the plane using GPS ground track provided by the WAAS GPS receiver built into the G5.

qCqmT7VXYu55kmVbAIcpreMjgYdqpPNYjtklBEUgiLroSQFI8615Z830IwY_hIlXdEew6blXlFxNkcnbiySXnJn3Vbv3bV20fsI3BL9fLiIUCnB4QV1qCdGzl7V5-5STRibu3pXwhaphrmRjw4AVcBEd0FmdkFnK33eknhiR8DfOnSuXW-DaC4QNUZaxoQjDIFIt5u7scCtBh4H5yf4xoaqjcd0lBBT6fFTRkKar4eg59nl97OrIlR97yOzHhwl1WNW0Psu8oSyH6kcsV6is_b-AmLroPiLwBZttrDTiadZFAmqLvU6oF2vr8uSBhR7Fr6sJSiy8M94EZ3J589dglr5M5z6ZtLZVy-_fVBzxkjT1bMxs2MjfprRYbtkNqN-UhYjobw5F9yuInAp_4o2Nje-d0rhcaqJst33iB_GO_fYH4ZQkw1PAOZsTo1dR1xQQ3FTLM9B84B34FUe_LswCyRZA8kPp80HxfyPiStue97pXa6kuSldBPJyoD9aWUerMUg4R8lMRbOYHu0Bgnr8TXfyO80Oi9B5evj1GmeSH_2144pjGR5_jGe1tl_qFF-GGsjHd78DOZ0AnD5PE_q94khGSgT3h-wBQ52UaHqUfd5oiyI1VkYknyK2l55tKL20T0hiWxMuLJv4cRLJU-ph0B8WyXDBPy180B6K62P9li5NxWRnLkT2THpMP=w640


Thanks,
Steve
 
I like my TT Gemini A/P a lot. I have a GRT Sport EFIS and there was a non-functioning "wing-leveler" in my plane when I bought it. That meant I also had a TT roll servo installed. I added a pitch servo and swapped the Gemini for the other unit. I can't remember the name but it was common I guess 10 or more years ago. People used to pair it with a separate altitude hold control.

The A/P works VERY WELL. I also like the additional Artificial Horizon that the unit provides (although I never look at the one in my EFIS!!). Very simple to control the A/P from the head unit OR the EFIS. I find myself controlling through the EFIS when I am on a GPS course, but through the head unit if I am simply using a heading hold. Ascents and descents are very simple using the Control head or the EFIS. I much prefer to control my climb and descents with the A/P. It locks itself on your chosen FPM setting. And I am either climbing at 25/25, cruising at 23/23, or descending at 18/23. I don't even have to look at the panel to see if I am at the right airspeed.

I don't have auto trim but I am never bothered by adjusting the manual trim now in the plane before I engage the A/P. The head unit tells me if I need to trim up or down, but since I am in the habit of setting trim first, I rarely receive a trim warning. As far as I know, the servos are adding absolutely zero drag on the controls when the A/P is disengaged. I know this from my own testing of the pushrod movement at the servo, but I believe it is also spelled out in the product literature.

I've never felt the A/P search on any axis while flying. It is my 1st A/P experience but I have to say I can't imagine having a better solution. I have the control wheel steering and engage/disengage wire to a hat switch on my control stick. I love to fly the Husdon River SFRA around Manhattan because it is literally 7-8 minutes by air from my hangar. There is a 300' altitude layer I choose to fly in between Bravo above and the non-transient layer down to the surface. I've never had any trouble maintaining my altitude accurately enough, but like most other flying these days, I like to use the A/P now. I line myself up at a chosen altitude and heading just south of the Verrazano Bridge and then engage the heading/altitude hold. I have to make one or two 5 degree heading adjustments as I follow the contours of the Hudson. These corrections are exactly one click each on the control wheel on the A/P head unit. Very simple. Disengage the A/P up past the Alpine Tower on the north end, 180 degree turn to the left, and start the process all over again to follow the river back down to the ocean.

To me, TT was the way to go because I already had their roll servo in my plane. They also gave me some amount of a discount for the rest of the gear because I bought it together and "traded in" my wing leveler. Having said that, I do love the capabilities I have with the A/P. I don't mean I can do more important things now, I just mean that when doing anything an A/P is made to do, mine does it well! If I had an approach-capable radio in my plane I could fly any approach that exists (I believe). I am a VFR pilot so I am not worried about that at the moment.

One other thing. I added the ARINC module. All I remember gaining from this extra piece of gear is the ability to intercept turns without running past the intersection first. But even as such, it was something I wanted to have. In the 2-3 weeks after I got my A/P but before I installed the ARINC, everything was just as good. Even though the plane may have been passing though waypoints before actually initiating the turn, you couldn't see it on the surface of the earth, or on the flight plan line on the EFIS. It always appeared to turn directly over the course line. Again, as a VFR pilot, none of this is significant anyway.

Good luck with your shopping! Andy
 
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Wow thanks guys for the input. I have a steam
Gauge set up now with very little panel space for anything else.
I have an adf I can get out of there and possibly use a Gemini, or a g5 in place of something out of the six pack.

I?ll probably upgrade to a GRT HXR or a G3 garmin in the future.
I?ve been god by many to use the TT bceuse of redundancy over the GRT but like the options I the GRT better. (At least from my reading)
Hadn?t really looked into the garmin options until recently and I emailed g3expert last week.

I?m looking to do a quick and simple auto pilot upgrade now for longer trips and what I have available budget wise and build on it later.

I have a century autopilot (Wing leveler in It now that is spermatic in its operation.) So I have that servo mounted but assuming I can?t or wouldn?t want to use that servo. ?

G3expert I need to know what I can delete from the 6 pack (would prefer turn slip indicator) and keep dg for back up for now) and a complete price for parts needed.

I halos have a 300xl I. The panel that I?d eventually upgrade to a gtn650
Although GRT has some good options for control on the panel that would work For practice and emergency for IFR approach?s.
 
The Gemini seems to have disappeared from TYs site and spruce shows it as special order only now.

Haven’t heard anything about the TRIO from anyone til now I’ll look at that option as well.
 
Turbo69bird said:
I?ve been god by many to use the TT bceuse of redundancy over the GRT but like the options I the GRT better. (At least from my reading)
Click to expand...

I think I can decipher the typos in the above quote. -:)

Your friend is correct: Buying the Trio or TruTrak will cost about $1K more than going the "autopilot-built-into-the-EFIS" route, and that's because you're buying redundant electronics, attitude and altitude sensors, etc. that you already own, inside the EFIS. And what you get are redundant electronics, sensors, etc. - the ability to let the autopilot fly the plane after a complete EFIS failure. (If you install a TT or Trio, you will want an external switch to switch the autopilot's ARINC lines from the EFIS to the GPS.) Only you can decide what that redundancy is worth. Another reason I prefer the Trio over the TT is that it has a simple display of a turn coordinator which functions whether the servos are engaged or not. If my GRT EFIS and backup Dynon D6 disagree, the Trio display will tell me if I'm wings level or not.
BTW, connecting a GRT HX or HXr to a Trio gets you all the functions and controls that the GRT autopilot has. You're buying redundancy.
 
BobTurner said:
I think I can decipher the typos in the above quote. -:)

Your friend is correct: Buying the Trio or TruTrak will cost about $1K more than going the "autopilot-built-into-the-EFIS" route, and that's because you're buying redundant electronics, attitude and altitude sensors, etc. that you already own, inside the EFIS. And what you get are redundant electronics, sensors, etc. - the ability to let the autopilot fly the plane after a complete EFIS failure. (If you install a TT or Trio, you will want an external switch to switch the autopilot's ARINC lines from the EFIS to the GPS.) Only you can decide what that redundancy is worth. Another reason I prefer the Trio over the TT is that it has a simple display of a turn coordinator which functions whether the servos are engaged or not. If my GRT EFIS and backup Dynon D6 disagree, the Trio display will tell me if I'm wings level or not.
BTW, connecting a GRT HX or HXr to a Trio gets you all the functions and controls that the GRT autopilot has. You're buying redundancy.
Click to expand...


Awesome info. Redundancy is big especially in IFR so that?s important.
I appreciate the detailed response and apologize for the typos. Usually reading and typing while working, and on a small I phone screen on top of it. Looked good when o re read it. I swear it changes it after I press submit.
 
Turbo69bird said:
Awesome info. Redundancy is big especially in IFR so that?s important.
I appreciate the detailed response and apologize for the typos. Usually reading and typing while working, and on a small I phone screen on top of it. Looked good when o re read it. I swear it changes it after I press submit.
Click to expand...

Lots of options these days for getting that redundancy without a stand alone AP.

Also don't trust that everything is as it seems. Get one of those stand alone AP's into an unusual attitude and they can get saturated and essentially "tumble" and forget which side is up.
 
Brantel said:
Lots of options these days for getting that redundancy without a stand alone AP.

Also don't trust that everything is as it seems. Get one of those stand alone AP's into an unusual attitude and they can get saturated and essentially "tumble" and forget which side is up.
Click to expand...

Hey Jeff, you thought you had a lot of info to think about and now another wrench thrown into the mix, LOL !!
 
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