AOA Port locations for an MGL IEFIS

[OneTallShort]

I seem to remember someone posting about using drilled out rivet stems as AOA pressure ports in the wing. Can't seem to find that message. I was wondering where chordwise worked best on the Sonex. Just to be clear, this is different than the AOA probes on the bottom of the wing. I'm feeding the AOA ports on a MGL Discovery Lite with the extender module (which includes the AOA ports).

http://advanced-flight-systems.com/Supp ... ndata.html has a chart, but no Sonex on it...Closest in my mind would be the RV-4 to -8 is 12" from leading edge, 6" forward of wing skin break position...

Thanks,

Gregg Short
gregg@gshort.com
(330)465-7531
Burbank, OH
Sonex 715, Center Controls Flap and Hydraulic Brakes Installed, Spar box closed up. Next, running wires to the back (under the spar)...and Pitot-static lines

[sonex1374]

Gregg,

You may be thinking of my AoA pickup using a hollow rivet. I suggest placing the rivet approx 6" from the leading edge in the bottom wing skin (NOT the location shown in the video....but the further forward location I mentioned). You can see more on my video.

https://youtu.be/ovAGCF5KIEc?t=11m10s

Jeff

[OneTallShort]

Jeff,

I think that may be the one. Just to clarify, you are only running a single port on the bottom for AOA, and not a second port on the top of the wing...right? How accurate do you find your AOA measurements from the Dynon? Are you currently using the 6" from leading edge dimension? Are you using 1/4" line, or something smaller for the AOA port?

Thanks,

Gregg Short

[sonex1374]

Gregg,

The Dynon only uses a single port for AoA (on the bottom of the wing). The other inputs are from the normal pitot and static ports. If you use a stand-alone AoA system, they'll either need to tap into your Pitot-Static system, or have at least 2 ports for AoA. If the MGL requires a top port then you'll have to experiment for a placement.

The Dynon system works well. After the video tour was filmed I moved the port forward to approx. 6" behind the leading edge, and that works better (it's more sensitive at lower angles or attack, but still very linear near the stall angle of attack).

The lines from the AoA port (hollow rivet) are 1/16" dia. I used the following, all from mcmaster.com:

1 each 5047K12 Moisture-Resistant Acetal Sngl-Barb Fitting Adapter for 1/16" Tube ID X 1/8" NPT Male Pipe. This is the fitting that adapts from the tube to the 1/8 NPT female fitting on the Skyview ADHRS.

1 pack 51525K211 Plastic Quick-Turn (Luer Lock) Coupling Nylon, Female X Barb, for 1/16" Tube ID.

1 pack 51525K121 Plastic Quick-Turn (Luer Lock) Coupling Nylon, Male X Barb, for 1/16" Tube ID. This is the disconnect fitting that I used at the wing root.

25 ft. 5006K51 Abrasion-Resistant Clear PVC Tubing 1/16" ID, 1/8" OD, 1/32" Wall Thickness.

You can use whatever tubing you want, though. Now you have all my secrets, the rest you'll have to get yourself!

Jeff

[OneTallShort]

Jeff,

Thanks for the additional info. The MGL unit can be configured as a single port or double port. Seeing that you've got good AOA numbers with a single port on the Dynon, I'm going to try and just run the single line where you've got it, and see how it works. The upper port is more problematic as it needs drainage, is more visible, etc. So if I can make it work without an upper port...all the better...

I think I'm going to try and run silicone aquarium line for the AOA port. I've already got the Tygon 1/4" line for the pitot-static lines installed per plans...

Gregg Short
Sonex 715