What's new
Van's Air Force

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

G3X remotes placement

JDA_BTR

Well Known Member
Wrapping up the tanks and about to skin the wings on my -8.

Thinking ahead to a G3X installation. Where on the 8 is a good place to put the ADAHRS? On my 14 it is on the back of the 460 on the panel and running the pitot-static-aoa there was good because the G5 takes pitot-static too.

What about all the other boxes....
 
It's a rough photo, I choose these positions.

If you need more I can add more views

G3X_Stuff.jpg
 
Wrapping up the tanks and about to skin the wings on my -8.

Thinking ahead to a G3X installation. Where on the 8 is a good place to put the ADAHRS? On my 14 it is on the back of the 460 on the panel and running the pitot-static-aoa there was good because the G5 takes pitot-static too.

What about all the other boxes....

I built an avionics shelf behind the panel, light weight batteries upfront and put most of the remote LRUs back by the bell crank. I have the Showplanes fastback which changes access, but not overall space.

i-MDszJhC-M.jpg


i-JJM9tzG-M.jpg


i-gbGFjtX-M.jpg


i-QLpvMCr-M.jpg
 
I think I'm correct when I say, the ADHRS fits on the top of the G3X, an integral part of the G3X.

Magnetometer is a different issue, is that what you meant?
 
The ADAHRS is the GSU25 and it is a separate unit. It can screw to the back of a GDU460 but in the 8 there might be a better place.
 
The biggest problem with mounting the GSU 25 to the back of the display is maintenance hassle. You are forced to disconnect the pitot/static lines and GSU 25 connectors every time you remove the display. When you own G3X you remove the display a lot because it provides such a huge access door for the instrument panel. Messing with the pitot/static lines also creates more chances of leaks in the system and can trigger more leak checking than you like.

If you install the GSU on a shelf instead the connectors and pitot/static lines hardly ever get tampered with which is a good thing.

There have been some reports of the GSU not passing the vibration test due to instrument panel flexing vs. a fixed shelf mounting.
 
Last edited:
On my flying 14A I do have the GSU25 on the back of the PFD 460. It passes tests and is very convenient there. I have push-connect air fittings and it isn't hard to move around if I want. But I haven't moved it in a very long time.

I'm not going to put it there on the 8 I think.....
 
Aaron that's an interesting shelf at the bell crank. Lots of room there and on the shelf you made; impressive really.
 
Do yourself a favor and DO NOT mount the GSU25 on the display.

Ok, why not? Not arguing, just curious what problems I can expect.

To the OP, I can't speak for the -8, but on my -6A all units are behind the panel except for the pitot/AOA (of course), and the magnetometer which is under the right wing tip. The GPS antenna is in the left wingtip to avoid COMM and engine noise.
 
Ok, why not? Not arguing, just curious what problems I can expect.

To the OP, I can't speak for the -8, but on my -6A all units are behind the panel except for the pitot/AOA (of course), and the magnetometer which is under the right wing tip. The GPS antenna is in the left wingtip to avoid COMM and engine noise.

Vibration/panel flexing can cause AHRS issues.
Heat and maintenance access are also contributors to problems.

From the install manual:
"Although mounting the GSU 25 to the threaded holes on the back of the GDU 4XX display is not
generally recommended due to instrument panel flexing."
 
Back
Top