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G3X Equipment mounting

JDA_BTR

Well Known Member
I'm looking ahead to where I'll mount things in my -8.

The question I have is how much can go under the seats instead of behind the panel and how is that best done?

In the panel:
GNX-375 (GPS/Xpdr)
GNC-255 (Comm/Nav/Intercom)
G3X touch screen (prob 10", maybe 7"), for engine/charts/EFIS
G5
Autopilot panel (maybe skip haven't decided)
The usual switches

Remote:
GEA-24 (instrument sub-panel)
GAD-27 (??? under the seats)
GSU-25 (??? under the seats, next to battery?, still have to run tubing to G5)
GMU-11 (probably on the right wing tip)
GAD-29 (why do we need this these days for one GPS input)
If wanted: second remote radio and audio panel (??? under the seats)
B&C backup alternator controller (instrument sub-panel)

Considerations:
Only one radio, and use headset bluetooth for radio/phone/etc
Maybe skip autopilot panel as no yaw director needed
Keeps number of remote items low
If second radio will get GTR-20 but then need audio panel
 
Suggestions

Some answers in bold below - I encourage to mount everything relatively close to each other since they wire up easier via CAN BUS

The question I have is how much can go under the seats instead of behind the panel and how is that best done?

In the panel:
GNX-375 (GPS/Xpdr)
GNC-255 (Comm/Nav/Intercom)
G3X touch screen (prob 10", maybe 7"), for engine/charts/EFIS
G5
Autopilot panel (maybe skip haven't decided)
The usual switches

Remote:
GEA-24 (instrument sub-panel)

Yup on sub panel behind G3X is good idea. There are 4 cables coming out of it however (the most of any of the boxes) so plan on wiring run

GAD-27 (??? under the seats)
I'd sub panel everything - all these units will communicate via CAN BUS and closer they are together the easier it will be

GSU-25 (??? under the seats, next to battery?, still have to run tubing to G5)
Bolts right onto back of GDU screen if you wish - easy

GMU-11 (probably on the right wing tip)
Yup - opposite wing of pitot heat smart

GAD-29 (why do we need this these days for one GPS input)
Believe you need this if you have 2 nav sources - 375+255 - maybe ask Xteam guys

If wanted: second remote radio and audio panel (??? under the seats)
Sub panel as well for me - I use G20A remote radio - you'll need audio panel now however

B&C backup alternator controller (instrument sub-panel)

Considerations:
Only one radio, and use headset bluetooth for radio/phone/etc
Maybe skip autopilot panel as no yaw director needed
Keeps number of remote items low
If second radio will get GTR-20 but then need audio panel[/QUOTE]
 
GAD-29 (why do we need this these days for one GPS input)
Believe you need this if you have 2 nav sources - 375+255 - maybe ask Xteam guys

I'm sure my wording is flawed, but I think this is why: Since the GAD 29 converts A429 to CANBUS you need the GAD29 so that all data from GNX375 is shared to CAN.
 
G3X Panel

Take a look at my build log..

Have everything on the removable panel except for the -11 which is in the tunnel..

Try and spend the extra bucks for the -750.. its worth it...


Enjoy.. Be safe...


Al
 
GAD 29

I'm sure my wording is flawed, but I think this is why: Since the GAD 29 converts A429 to CANBUS you need the GAD29 so that all data from GNX375 is shared to CAN.

There are no ARINC 429 inputs on either the G5 or the G3X Touch, the GAD 29 is required for this purpose. A single connection from each navigator to the GAD 29 will facilitate the distribution of that particular navigation info to all equipment on the CAN bus. It acts as a hub in a sense, negating the need to wire the navigator to each piece of equipment in the system that consumes the 429 navigation data.

Thanks,

Justin
 
GSU 25 Mounting

I'm looking ahead to where I'll mount things in my -8.

The question I have is how much can go under the seats instead of behind the panel and how is that best done?

In the panel:
GNX-375 (GPS/Xpdr)
GNC-255 (Comm/Nav/Intercom)
G3X touch screen (prob 10", maybe 7"), for engine/charts/EFIS
G5
Autopilot panel (maybe skip haven't decided)
The usual switches

Remote:
GEA-24 (instrument sub-panel)
GAD-27 (??? under the seats)
GSU-25 (??? under the seats, next to battery?, still have to run tubing to G5)
GMU-11 (probably on the right wing tip)
GAD-29 (why do we need this these days for one GPS input)
If wanted: second remote radio and audio panel (??? under the seats)
B&C backup alternator controller (instrument sub-panel)

Considerations:
Only one radio, and use headset bluetooth for radio/phone/etc
Maybe skip autopilot panel as no yaw director needed
Keeps number of remote items low
If second radio will get GTR-20 but then need audio panel

As long as you are able to secure the GSU 25 to primary aircraft structure under the seat, it may serve as a good location for it. There is a chance however that this location may cause some issues. Exhaust pulse on the bottom of the aircraft has proven troublesome for this location in the past. Worst case scenario, you will end up having to relocate the GSU 25 at that point, requiring re-routing of the pitot/static/AOA lines.

Mounting the GSU 25 directly to the display significantly complicates maintenance access. Without the GSU 25 mounted to the display, you can remove the 4 fasteners that are holding the display in place, and you quickly have access to the forward side of the instrument panel. Instrument panel flex may also present a problem. We see the most success with shelf or bulkhead mounting. There are some good examples in some of the older forum posts on this topic.

Section 19.4.2 is the section of the Installation Manual that provides the general considerations that should be addressed when choosing an installation location for the GSU 25.

Thanks,

Justin
 
I'm looking ahead to where I'll mount things in my -8.

Autopilot panel (maybe skip haven't decided)

...

If second radio will get GTR-20 but then need audio panel

I’m definitely not an expert but I have yet to find an answer as to why anyone in a light GA airplane has an autopilot control head on the panel with a G3X. My RV-4 had a G3X with a Garmin two axis autopilot and I never once wished I had a control head for any function that I could (or could not) accomplish through the G3X screen. Just valuable real estate completely wasted, unless someone can enlighten me...

As for the audio panel, I want to say I just watched a Garmin demo video where the top inch or so of the G3X served as a “virtual” audio panel. Isn’t that a function of the G3X now? Can the G3xpert chime in here?
 
I’m definitely not an expert but I have yet to find an answer as to why anyone in a light GA airplane has an autopilot control head on the panel with a G3X. My RV-4 had a G3X with a Garmin two axis autopilot and I never once wished I had a control head for any function that I could (or could not) accomplish through the G3X screen. Just valuable real estate completely wasted, unless someone can enlighten me...

As for the audio panel, I want to say I just watched a Garmin demo video where the top inch or so of the G3X served as a “virtual” audio panel. Isn’t that a function of the G3X now? Can the G3xpert chime in here?

All I can say is once you fly with an AP control panel you will wonder how you lived without it (at least for IFR it's invaluable).
I won't install a panel without one.
 
I have the autopilot panel in my 14. I use it all the time for the buttons but not the knobs.
 
Best thing since sliced bread

I have the autopilot panel in my 14. I use it all the time for the buttons but not the knobs.

I use my AP panel all the time but I use the knobs a lot. My goal is to keep my HDG sync'd with my course at all times. Easy with a push of the HDG knob on the AP panel. This way, if I switch from NAV mode to HDG I remain on course.

If I'm getting headings from ATC, a simple twist of the HDG knob makes it easy to comply. If I'm doing my own navigation, I use the HGD knob to dial in the new heading. I like to use the extended course line that pops up on the G3X map to determine the course I want to fly.

I also try to keep the ALT sync'd so I get an alert if I deviate more than 200 feet. I also use the ALT to give my self a warning even when fly by hand.
 
Good tips. I use the G3X knobs for those mainly. I do use the thumbwheel to set climb rate after takeoff forgot about that.
 
I'm looking ahead to where I'll mount things in my -8.

The question I have is how much can go under the seats instead of behind the panel and how is that best done?

In the panel:
GNX-375 (GPS/Xpdr)
GNC-255 (Comm/Nav/Intercom)
G3X touch screen (prob 10", maybe 7"), for engine/charts/EFIS
G5
Autopilot panel (maybe skip haven't decided)
The usual switches

Remote:
GEA-24 (instrument sub-panel)
GAD-27 (??? under the seats)
GSU-25 (??? under the seats, next to battery?, still have to run tubing to G5)
GMU-11 (probably on the right wing tip)
GAD-29 (why do we need this these days for one GPS input)
If wanted: second remote radio and audio panel (??? under the seats)
B&C backup alternator controller (instrument sub-panel)

Considerations:
Only one radio, and use headset bluetooth for radio/phone/etc
Maybe skip autopilot panel as no yaw director needed
Keeps number of remote items low
If second radio will get GTR-20 but then need audio panel

Hi,
I`ve mounted the GAD-27, GEA-24, GSU-25 and my traffic device (europe) on a shelf behind the panel.
In the panel I have a GDU-460, GNC-255, GMA-245, GMC307 and a G5, further I have a smaller version of the Vans map box installed.
For the rear seat I have a GDU-450 and where normally the battery goes I have a GTX-23ES Transponder. Further I have a GMU-22 in the tailcone and a GMU-11 in the right wingtip.

See the attached pictures (pictures were taken during building phase.. all normal nuts were replaced by locknuts or nutplates..)

I tried as best as I could to separate the signal wires from power wires as you may see in the first picture. Towards the firewall are the signal wires and towards the panel the power wires.

As you can see in the last Picture, I have left some space above the autopilot panel to install a GPS175 in the future (I would move the autopliot panel up and then the master caution and warning lights away)..
 

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See the attached pictures (pictures were taken during building phase.. all normal nuts were replaced by locknuts or nutplates..)

That’s a beautifully neat install!

What’s the purpose of the diodes on the keep alive terminal block?

Did you 3d print those static line clips? (They are a great idea). Can you share some photos of them?

What is the speaker for?
 
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Hi Trent,
thank you.
The diodes are used for the second power-in for the GDU-460, GEA-24 and GSU-25. I have either the keepalive power or the backup battery and to not discharge one or the other they are blocked over the 25A schottky diode.

I used 3D printing in several spots.. the one mentioned is only a „figure 8“ to connect the pitot and static line.. I also printed some for 3lines (3rd is AoA) with a slot for a #8 nut included.. so on top of my shelf are the pitot lines and below some power lines.. I also printed a bracket to make a strain relief for the cables from the CB‘s as well as some brackets to mount the CO Monitor..

The speaker is to listen to the ATIS before I wear the headset.. But I rarely use it and would not install it again..

Have a great day down there :)
 

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Hi Yves,

Makes sense re the diode - thank you.

Those are great ideas re the printing, especially the CB strain relief clips. Nice!
 
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