What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

GRT AUTOPILOT

Scott Hersha

Well Known Member
I’m installing a new GRT autopilot (2-axis) on my RV4. I have a Horizon 10.1 and Mini-X, installed last year. The install manual suggests either one “ENGAGE/DISENGAGE” switch for both axis’, or two switches, one for each axis (roll/ trim). From those that have done this, is there a relative advantage in having the ability to select just one axis of the autopilot? It’s not a difficult thing to do, but should I have that option, + extra switch? I’m trying to imagine when I would want one axis without the other. My vertical autopilot will have the capability of VS, IAS, or VNAV for climbs or descents.
 
One for both.

I did not install mine but I have sport sx driving my two axis grt AP. I have one button to engage disengage. No , I don’t one phase without the other.
 
I use the Trio Pro Pilot in separate axis all the time. Frequently turning off alt servo to change alt while letting the roll servo keep me level and on course in imc.
 
No need

I've been using a GRT autopilot for many years and never even thought I would like to turn off one axis or the other. It's just one more switch and a couple of wires that will really add nothing to the system...

Like my old buddy Stein says, just my .02 cents worth.. and you get exactly what you paid for..
 
I use the Trio Pro Pilot in separate axis all the time. Frequently turning off alt servo to change alt while letting the roll servo keep me level and on course in imc.

One function of such a button(s) is to disengage the autopilot, possibly as low as 200’ agl; or in an emergency, such as a run-away. For this, one button is easier and quicker than two. Of course the Trio offers you a choice: two independent buttons on the control head, and one ‘both axes’ button on the stick. Sort of the best of all worlds.
 
GRT offers the “button on the stick” extra option too. I don’t have an extra button on my stick. Think I’ll go with the single “engage/disengage” switch on the panel. More simple....
 
GRT Autopilot

Why not just use the auto pilot button control in the GRT to shut off one axis. I do it all the time where I will keep the altitude hold on and but able to steer the plane as desired.
 
One function of such a button(s) is to disengage the autopilot, possibly as low as 200’ agl; or in an emergency, such as a run-away. For this, one button is easier and quicker than two. Of course the Trio offers you a choice: two independent buttons on the control head, and one ‘both axes’ button on the stick. Sort of the best of all worlds.

+1

The ability to quickly disconnect the AP is a safety issue IMHO. Having it on the stick speeds the process, which I have had to use in traffic conflict situations.

another reason for one button is to be able to use it to also engage the AP. I really like that feature and I would find it annoying to have to do it twice. Very easy to manipulate the individual axis' on the screen, though I don't think I have ever done so in 700 hours.
 
Last edited:
Thanks Len. I didn’t know I could do that. One button for me. I’m headed over to Micro-Center to pick up NO push buttton switches. I have a bag of NC switches (not sure what I would do with them), but no normally open ones.
I ordered the servos yesterday. Should have them in a couple weeks - enough time to get them installed before the trip to SNF.
 
3 buttons

I've got the disengage button on the stick, and the engage/disengage for pitch and roll on the panel. Disengage on the stick seems like a mandatory safety feature, and I do like to be able to engage either roll or pitch independently. I've only got just under 50 flight hours so my view on this might change, but it was so easy to install, why not? I just used tiny little pushbuttons.
 
Last edited:
I’m installing a new GRT autopilot (2-axis) on my RV4. I have a Horizon 10.1 and Mini-X, installed last year. The install manual suggests either one “ENGAGE/DISENGAGE” switch for both axis’, or two switches, one for each axis (roll/ trim). From those that have done this, is there a relative advantage in having the ability to select just one axis of the autopilot? It’s not a difficult thing to do, but should I have that option, + extra switch? I’m trying to imagine when I would want one axis without the other. My vertical autopilot will have the capability of VS, IAS, or VNAV for climbs or descents.

I had only the one and went back and added both since the other is a short cut on the EFIS for level flight and direction along with the 180 deg turn
 
Back
Top