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GRT AHRS location

Maxrate

Well Known Member
It looks like a search has a lot of these older AHRS units located in the aft fuse on a shelf. I'm going with some inexpensive GRT equipt for the time being with Garmin upgrades at a future date. GRT says it is acceptable to mount the AHRS under the dash and the mag on the wingtip rib. Has anyone else mounted behind the instruments and care to weigh in?

 
It looks like a search has a lot of these older AHRS units located in the aft fuse on a shelf. I'm going with some inexpensive GRT equipt for the time being with Garmin upgrades at a future date. GRT says it is acceptable to mount the AHRS under the dash and the mag on the wingtip rib. Has anyone else mounted behind the instruments and care to weigh in?


I had mounted my dual AHAR right behind the FW (cold side) with zero issues. My Magnetometers were mounted behind the luggage area up on top on a shelf that I had created and again with no issues in 760 hours of flying.

Hope this helps.
 
Same setup

In my 7A, I mounted the GRT AHRS between the subpanel and firewall and the magnetometers in the wingtips. Been flying this way about 550 hours, no issues.
 
Charlie, how do you access the AHRS for repairs and such? Under the panel or did you cut a hole in the sub large enough to pull the unit out if needed. I?m trying to avoid laying under the panel if I can avoid it. Thx
 
Good thought

The builder of my RV-9A mounted the AHRS just aft of the firewall on the pilot's side. It appears to be a great spot in terms of rigidity, etc. But access to this location is extremely difficult, at least in my slider.

The magnetometer was mounted under the tail fairing and has worked perfectly so far. Recently replaced the old analog magnetometer with the digital one and it continues to work fine back there. Access to that location is of course very easy.

Working on my panel has given me a real appreciation for the benefits of planning for access during construction.

Charlie, how do you access the AHRS for repairs and such? Under the panel or did you cut a hole in the sub large enough to pull the unit out if needed. I?m trying to avoid laying under the panel if I can avoid it. Thx
 
Charlie, how do you access the AHRS for repairs and such? Under the panel or did you cut a hole in the sub large enough to pull the unit out if needed. I?m trying to avoid laying under the panel if I can avoid it. Thx

Mine was installed in the same area and the shelf was mounted in such way that when I removed the screws that held the shelf, it would drop down. So, removal was no issue.
 
I do need to do some "RV yoga" when it's time to work on things. But, it's not too bad. The wire connectors are relatively easy to access and I mounted the AHRS on a couple of pieces of aluminum angle that I can drop down by removing a few screws. The only time in 4+ years that I've needed to access it was recently when I installed a TCW battery backup system.
 
not sure if this image will show up. How mine is installed. not flying yet.

69484617_10156695602166538_466846632789409792_n.jpg
 
Access Panels

I have a 9A.
I mounted my double GRT AHRS between the sub panel and the firewall.
Like the other post I put it on a shelf with screws that can be removed from the
bottom.
BUT..one of the best things was making two access panels in the top skin.
Another forum poster, CAJUNWINGS, is converting a 9A to a 9 and has done
a complete redo of the whole plane. He came up with the idea of making the
two access ports. They have paid for themselves with the access.

IMG_0630-M.jpg


This is the skin before install, you can see the marks for the panel, sub panel
and the firewall.
COMPLETELY WORTH THE EFFORT.
 
Great posts. Just the info I was hoping for. Bayou I got the dimensions from Don and installed the skin access holes also. Thanks for the input!
 
As someone who has done some RV yoga...

...I declare this to be a brilliant idea.

I have a 9A.
I mounted my double GRT AHRS between the sub panel and the firewall.
Like the other post I put it on a shelf with screws that can be removed from the
bottom.
BUT..one of the best things was making two access panels in the top skin.
Another forum poster, CAJUNWINGS, is converting a 9A to a 9 and has done
a complete redo of the whole plane. He came up with the idea of making the
two access ports. They have paid for themselves with the access.

IMG_0630-M.jpg


This is the skin before install, you can see the marks for the panel, sub panel
and the firewall.
COMPLETELY WORTH THE EFFORT.
 
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