Dynon OAT placement question

Can someone recommend an area to place the Dynon OAT probe on their 7A that is working ? A picture would be worth a thousand words ! Thank in advance !

I just went through this.

https://vansairforce.net/community/showthread.php?t=190703

I opted for installing it on the middle inspection panel of the left wing. Others recommended fuselage under the left horizontal stab. The latter would have been easier in terms of running the wiring to the ADAHRS, but I was advised by both Dynon and Advanced Flight that under-wing was preferable. It turned out to be pretty easy to run the wiring through the left wing, into the fuselage, and down the tunnel to the ADAHRS. The AOA and pitot tubing was more of a challenge. But do-able. If you install it in the wing, you will almost certainly have to splice the cable to the OAT probe. It's only 10 ft long. I don't know if that necessary if you decide on the tail location.


ETA: since my probe is mounted on the inspection panel, I opted to put the splice right there and use a molex connector so I can disconnect the probe and keep the whole thing from having to hang loose on the wiring when the panel is removed.

I installed mine under the left wing in the wing root fairing,

Dynon OAT

MacCool said:

I just went through this.

https://vansairforce.net/community/showthread.php?t=190703

I opted for installing it on the middle inspection panel of the left wing. Others recommended fuselage under the left horizontal stab. The latter would have been easier in terms of running the wiring to the ADAHRS, but I was advised by both Dynon and Advanced Flight that under-wing was preferable. It turned out to be pretty easy to run the wiring through the left wing, into the fuselage, and down the tunnel to the ADAHRS. The AOA and pitot tubing was more of a challenge. But do-able. If you install it in the wing, you will almost certainly have to splice the cable to the OAT probe. It's only 10 ft long. I don't know if that necessary if you decide on the tail location.

Click to expand...

similar on my 7A - the OAT probe is installed entirely in wing under the number most inboard inspection panel and does not stick into the airstream. Seems to work just fine. TAS calculation match GS well.

Thanks for the rapid responses. It looks as though the wing is the preferred location. Since I have to run the pitot lines, I might as well bite the bullet and pull wire for the OAT probe as well.

Dpnm

I learned this the hard way. I had a nine degree OAT error with the probes mounted under the tail empennage fairing. While this equates to about a two knot TAS error (reading higher than actual) the real risk was not knowing when OAT dropped below freezing. I had a brief experience with clear ice when IFR clipping the top of a cloud. OAT was reading 35 degrees.

Reading the literature it is clear that exhaust gas is present along the fuselage - causing false (high) OAT readings. On the new RV-8 I mounted the OAT probes on the bay outboard the wing bell crank, the same bay as the Pitot. This is well outside the reach of exhaust gas and the wires are outside the bell crank area.

Doing comparison with ADS-B winds aloft data on long cross countries I find the OAT readings to be dead on.

Carl

Between the AOA and pitot tubing, the ADAHRS harness, the OAT wires, as well as the manual elevator trim cable and the rest of the wiring...the snap bushings in the bulkeads of that center tunnel are pretty darn crowded. I think I can get the AOA/pitot tubes through there...but it will be tight.

Have mounted them in Lt & Rt under wing inspection cover plates, Lt rear side fuselage under Horiz Stab, Lt Horiz Stab bottom skin & outboard wing rib inside wing tip with great results.
Places I've tried with not so great results are wing lower root fairings & side fuselage NACA scoops.