Re: Trim with the Garmin G3x
I believe the servos have the means of detecting the pressures and energy being applied to the controls.
Re: Trim with the Garmin G3x
I'm not familiar with the G3X, so I don't know anything about its integrated trim controller. However, for smart trim control, you don't really need position feedback. It will adjust the rate based on your airspeed.
If you want trim position indication on your G3X, you will need to install a trim position sensor. Kitfox sells a kit for this. It's easy to install. I installed it because I wanted to be able to set takeoff trim easily.
I think what Eddie is talking about is letting the Autopilot auto-trim. For this, he's right, the autopilot servos do have torque feedback, and can trim control forces out so that the autopilot servos aren't loaded too heavily and so that when you turn the autopilot off, the airplane is already trimmed. I don't know if your G3X has this built in. Dynon Skyview can do this if you have the optional AP panel.
Re: Trim with the Garmin G3x
Thanks Brian. I think I prematurely jumped to the AP functioning and trim with the G3X. Since I have the professionally assembled harnesses I do have wires to hook up a trim position sensor installed. I even have the trim LED bar from Ray Allen but I would need a sensor. I don't aim to install it. Trim is felt in your hand with the exception of setting trim for departure. I can count to three or whatever it takes to set the trim just as I did during the transition training at Stick and Rudder. While speaking of the Safety Trim, be sure you are getting the "Safety Trim Booster". I got mine from Kitfox. I have looked at the TCW website after the fact and note that the Safety Trim "Booster" is not listed on their site. They do have a Safety Trim. I have no idea what the difference is but I have had John McBean specifically ask if I had the "Booster" back when I was having auto pilot servo trouble.
Re: Trim with the Garmin G3x
Hmm, booster eh... i'll have to find out about that.
I've decided to pass on the AP right now.
But sounds like a trim position sensor - if not too expensive - is what's needed here too. So many things.
Re: Trim with the Garmin G3x
Just kinda reviewing this post.
I see we have two aspects that we are discussing. The G3X will adjust the rate at which the trim will move and its based on the airspeeds that you program in as when to move fast and when to move slow when you hit the switch. The G3X wont actually auto trim unless you have the AP as I believe Brian states how Dynon works. What the Garmin lacks is the amperage needed to drive our Pitch servo motor hence the Safety Trim Booster.
FWIW the Vertical Power unit also has the "trim rate" function for low and fast air speeds.
Re: Trim with the Garmin G3x
Quote:
Originally Posted by
efwd
The G3X wont actually auto trim unless you have the AP as I believe Brian states how Dynon works.
"Auto trim" is a deceiving term. One might think that the airplane will keep itself in trim while you're flying it. It won't. It allows the autopilot to operate the trim to alleviate the load on the AP pitch servo, just like the pilot would.
Quote:
Originally Posted by
efwd
What the Garmin lacks is the amperage needed to drive our Pitch servo motor hence the Safety Trim Booster.
Just to clarify, by Pitch servo motor, you mean the trim motor, not autopilot servo correct? The Vertical Power and Advanced Control Module both have "smart trim" built in, and can supply the trim motor with adequate current. It might be something to consider when deciding to spend the $$$ on one of these systems. They incorporate a lot of functionality into a single red box.
Re: Trim with the Garmin G3x
Quote:
Originally Posted by
efwd
Just kinda reviewing this post.
I see we have two aspects that we are discussing. The G3X will adjust the rate at which the trim will move and its based on the airspeeds that you program in as when to move fast and when to move slow when you hit the switch. The G3X wont actually auto trim unless you have the AP as I believe Brian states how Dynon works. What the Garmin lacks is the amperage needed to drive our Pitch servo motor hence the Safety Trim Booster.
FWIW the Vertical Power unit also has the "trim rate" function for low and fast air speeds.
Right. I was just reviewing the VPX docs as I am planning on using it. The trim is locked at 1 amp, so no good either.
Re: Trim with the Garmin G3x
yes, pitch trim motor not the AP servo.
Re: Trim with the Garmin G3x
Sorry to bring back an old thread. Been searching on the trim motor issue.
Is the current solution still to install the booster module?
Currently drafting wiring diagrams for VPX GSA28 integration and it looks like regardless of configuration the GSA will supply the trim motor and require a boost.
Confirmation would be excellent.
TIA!
Pat.