ADAHRS Tailcone Tray

[J Twilbeck]

A while back I designed a tray to install the Dynon ADAHRS units in the tailcone. I designed the tray to install in the top of the tailcone hanging from the upper stringers. The tray was made from scrap 6061-T6 aluminum and channel. All the rivets are solid aluminum #3 button head rivets. I used my iPhone's inclinometer to install the tray at the same plane as the door frame longerons which are the straight and level flight reference point on the RV-10. The tray after installation measured in the same plane as the longerons on all axes.


This is the 3D model I made to design the tray.

I ran an analysis on my design and it easily passes a 10g crash load.

Here is a picture of it clecoed in place.

On my site I posted links to some full size drawings of the parts if your interested in making the tray. With the full size prints I built the tray in an afternoon.

Hope this helps a future builder.

Enjoy,

 

[Bluelabel]

Nice

Thanks..... just about to start on mine......

 

[Dorfie]

ADAHRS tray

Looks real nice. I am very close to this stage. Few questions/thoughts:
How well will the ADAHRS withstand the very high temps so close to the top skin in a/c in blazing sun? Will insulation between ADAHRS and top skin help if themp is an issue?
Can the magnetometer be installed in close proximity to this tray?
Thanks.
Johan

 

[J Twilbeck]

Looks real nice. I am very close to this stage. Few questions/thoughts:
How well will the ADAHRS withstand the very high temps so close to the top skin in a/c in blazing sun? Will insulation between ADAHRS and top skin help if themp is an issue?
Can the magnetometer be installed in close proximity to this tray?
Thanks.
Johan

Many times in other aircraft the ADAHRS units are installed in the wing as far inboard as possible which is a very small, easily heated location with close proximity to the upper aircraft skin. These aircraft have not experienced any issues with heat as far as I know. I plan on painting the top of my aircraft white to help reduce heat build up. Dynon publishes an operating max temp of 60 Celsius which is 140 Fahrenheit. I don't suspect any thermal issues.

The Dynon ADAHRS modules include the magnetometer ie. it's built in not remote.

Hope that helps. Thanks,

 

[awmuhs]

ADHRS mounting tray

I am using dual Dynon ADHRS and put mine in about the same place. Instead of hanging the tray I mounted to the longerons making sure that I was at least 24" from the master relay which is mounted adjacent to the battery. I put it low enough so that I could get a stubby screw driver above the shelf to put the Dynon ADHRS screws in. For additional bracing, to avoid any vibration, I also bolted it to the adjacent bulk head.

The 24" comes from a Dynon tech that told me to be at least that far from any magnetic coils.

Alan Muhs
RV10, just finished fitting the cowl
520-247-6232

 

[bpattonsoa]

I did the exact same in my -10 except the legs are slightly longer. I put a brace to one longeron before putting on the top skin because it was a bit wobbly.

Works fine

 

[paul330]

Very similar to my solution:

http://www.vansairforce.com/community/showthread.php?t=85709

 

[togaflyer]

How difficult will it be to access the equipment for repair/replacement down the road.

 

[bpattonsoa]

I put nutplates on the vertical members so you just remove the screws that hold the tray and the tray with the ADHARS comes out. Very small amount of metal in the nutplates does seem to matter not hurt it. Uses brass screws.

 

[J Twilbeck]

How difficult will it be to access the equipment for repair/replacement down the road.

I plan on installing the units with a nut and bolt. Unscrew the nut and bolt and slide the ADAHRS off the tray...done. The tray is located 5in in front of the frame so you could slide the boxes aft or fwd whichever is easier.