Garmin G3X Install question

At AOPA last week I was talking to the Garmin Rep about installing a dual screen G3X system in my plane. He said the proper placement of the magnetometer is crucial. Anybody have experience with where it will work well or will not work well, installation considerations etc???

Rear deck of the fuselage...

We mounted my G3X magnetometer on the rear deck of the fuselage (RV-6) where the horizontal stabilizer is bolted on. On the far right side of the image you can just see the spar for the HS. The two lightening holes make a convenient drop-in spot. The small arrow in black ink indicates 'plane goes this way'.

It is just about as far away from the panel as you can possibly make it...and seems to work just fine.

I should have parts in hand in within a week, but it's going to be interesting in the RV-8.

The aft deck location in the -8 simply doesn't exist. On the 8, the front spar of the horizontal stab is very close to the back of the "turtledeck" unlike the side-by-side airplanes. Putting it between the spars there is plenty of room, but it is literally inches from the (steel) elevator torque tubes.

putting a shelf across the upper longerons worked for my previous magnetometer (A Honeywell/BMA) but that was before I mounted the TruTrak pitch servo less than two feet from that location.

Garmin suggests the outer wing panel is the preferred location, but of course wiring and the steel pipe counterweights may be an issue.

I'd be very interested in anyone flying an RV-8 with a good magnetometer location (and TT autopilot) or anyone flying any RV with a good wing mount location.

RV-3

This is the tentative location for ours in the RV-3:



We noticed good performance in Doug's plane with that location when we flew it back from Oshkosh, and if it turns out to be a problem, it is pretty easy to move. I rejected this location in the RV-8 for my GRT magnetometer because I got a minor change in magnetic heading with elevator position (elevator arms) when I tested it, and the mid-fuselage position was perfect. The -3 is so small, the mid-fuselage position would be too close to the pitch servo (as was suggested by flyeyes...so we'll see how this works.

Paul

Our G3X system is on its way. Were building a rv-10 with a flight line A/C system.

We have really been drawing a blank on the location of the magnetometer.

The 10 amp dc motor in the middle of the airplane is causing my heartburn.

I think the aft deck is a good idea. Will report back.

Sonny,
Coming back to this thread as I pulled the trigger on a G3X system this week (to get the rebate) and I'm thinking ahead. Is the pitch trim servo and cables (which for you non -10 builders is mounted right in front of the aft deck) a cause for concern?

I'm thinking of mounting it on a tray somewhere mid-tailcone around the F-1008 frame. Not as easy to mount it there but since I'm using Van's AHRS shelf next to the battey, wiring the connection between the magnetometer and the AHRS will be a breeze. Of course I don't have to worry about an A/C motor like you do.

sonny junell said:

Our G3X system is on its way. Were building a rv-10 with a flight line A/C system.
We have really been drawing a blank on the location of the magnetometer.
The 10 amp dc motor in the middle of the airplane is causing my heartburn.
I think the aft deck is a good idea. Will report back.

Click to expand...

Hi Sonny,

It shouldn't cause you any heartburn at all. We have lot's of these installed in similar setups with AC in the back of RV10's. Put it wayyyy back in the fuse or out in the wingtup and you shouldn't have a problem. The dealer you purchased it from should be able to give you guidance on that (if they know RV's at all or have experience installing them)...

If you have a problem, we have some really nice CNC'd mounts we made/offer for the GMU that will make your task easy for alternative mounting of the GMU to the wingtip rib or other places in the aiframe if you can't use the standard mid empecone area. We've spent lots of time with a GMU hooked to a laptop using the Garmin tool to do magentic mapping of airfames and also to see where acceptable placement of the GMU works and doesn't work at....been there done that. Again, call the dealer and see what their experience has been, perhaps they have better or different data.

Cheers,
Stein

Here is a link to our previous post on where to mount the magnetometer. There are pictures included in the previous post as well.
http://www.vansairforce.com/community/showthread.php?t=64752&page=2

Todd, Garmin did a really nice job on the VP-200 G3X integration. Should have pics in a while. Includes mode display, trim and flap position on the EFIS, and sends engine data, GPS GS, and IAS to VP-200.

Marc,
That's great to hear! Can't wait to get it all installed and fired up for the first time.

First thing you'll need to do is a software upgrade. It's been a while....

Marc,
Yep, I've got rev 17 installed. Just looked at your website and see that 21.1-r is current. Should I install 20.6j first (which I downloaded sometime ago just never got around to installing), or can I skip it and go right to 21?

According to the VP-200 Software Update Page, you will need to update to 20.6j first, then to 21.

Yes, 20.6 file #2 first, then 21. We moved to a new file format.