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DYNON OAT PROBE

R

rv7guy2

Active Member
Hi There

I was wondering whether any of the DYNON flyers out there could tell me where they have mounted their Outside Air Temperature probes? I am at a quandry about where to put mine. I was considering placing it on the bottom wing fairing skin between the left wing root rib and the fuselage side. That would give me plenty of cable to hook it up, and also keep it out of the heat of the exhaust and sun. What do you think.

Dave C
RV-7 C-GCPD (getting real close to inspection)
 
Which one?

Mine hooked up to the remote compass and I mounted that in the left wing tip, so I mounted the probe in the bottom wing skin next to the access cover.
Maybe you have the probe going to the EMS direct?
I have the D10A
 
To the 10 or 10A or EMS

Mine is hooked up to my EMS as I chose to stop tinkering with the dang thing and not upgrade to the 10A and just fly the thing. In doing so, I ran my wires out the fuel line exit point of the fuselage and onto the bottom of the wing next to the access panel. Gives me a good reading there....................even though............I have BLACK wings :eek:
 
Please note that there are two models of OAT probe from Dynon for the 10 or 10A EFIS. One model is designed where you can not change the cable length and the other is not sensitive to cable adjustments. I originally had the fixed length unit and with the magnatometer behind the baggage bulkhead on my 9 I had limited choices on where to mount the OAT--therefore it was mounted under the tail close to the tie down. I was concerned about the influence of exhaust heat at this location so I got the other type of OAT from Dynon and ran the line out the left wing and moved the probe to an access panel under the wing. This avoids the affect of exhaust and/or engine heat. Works great in this location.

Cheers,

db
 
I mounted mine in the left wing root approximately opposite the rear stick. Out of sight and windstream and still getting good temp readings.

Glenn
 
We got ours when we ordered the D100 and D120. Just getting round to fitting and wiring and come across the instructions relating to 3 wires................ D'Oh, ours only has 2 !

Emailed Dynon and the swift reply said that you can use either, but, if you use the 2 wire one, it has to go into the EMS and then connect to the D100 via the DSAB.

I almost understood that, now, where's Bob Nuckoll's book :confused:
 
I mounted mine in the NACA scoop on the right side of my RV-6A. Works well there and no noticable difference in cooling from the vent.
 
I have my Dynon OAT under the left wing outboard about 3 ft. My AFS 2500 OAT is in the pilot air vent. The OAT in the air vent NACA reads consistently 8 degrees f higher in cruise--due to radiat heat off the cowl. I had an OAT in the NACA vent on a Mooney also--it also ran slightly high in cruise. The under wing unit is more accurate in my application.

Cheers,
db
 
db1yg said:
I have my Dynon OAT under the left wing outboard about 3 ft. My AFS 2500 OAT is in the pilot air vent. The OAT in the air vent NACA reads consistently 8 degrees f higher in cruise--due to radiat heat off the cowl. I had an OAT in the NACA vent on a Mooney also--it also ran slightly high in cruise. The under wing unit is more accurate in my application.
Click to expand...
I've flown in one RV-6 that had the OAT in the NACA scoop on the side of the forward fuselage. It was winter, and we were using cockpit heat. The indicated OAT would change by several degrees depending on how much heat was selected. I surmise that the back side of the OAT probe was being heated by cockpit air. I've read similar reports from other RV flyers.
 
The 8 degree differential was taken in warm weather with no cabin heat selected and the vents partially open to the cockpit. It is possible that radiant heat from the engine through the firewall could contribute some to the differential by warming the interior under the panel and then the back of the probe. Long story short is that my experience through two airplanes was that NACA vent install close to the firewall is not as accurate as under the wing install.

Cheers,

db
 
rv7guy2 said:
Hi There

I was wondering whether any of the DYNON flyers out there could tell me where they have mounted their Outside Air Temperature probes? I am at a quandry about where to put mine. I was considering placing it on the bottom wing fairing skin between the left wing root rib and the fuselage side. That would give me plenty of cable to hook it up, and also keep it out of the heat of the exhaust and sun. What do you think.

Dave C
RV-7 C-GCPD (getting real close to inspection)
Click to expand...
One thing no one is talking about is how you power that OAT probe with the Dynon.

It connects to the remote compass, so figure out where you want to put that thing and then use that as your guide as to the location of the probe.

In my case, the compass is mounted in the tail cone. Rather than running some more wires forward in the limited space I had, I elected to put the probe in the tail. If you look at this picture you will see the probe and it's wire in the tail.

Some might argue that this will give you an inaccurate reading because it is not mounted in the slip stream, and that may be true, but I'm VFR only so what do I care. Besides, the OAT probe in my truck isn't mounted on the outside and it is fairly accurate.
 
What temperature do you want to measure; the actual temperature of the air, or some combination of exhaust, sun, or stagnation rise from forward speed. My Dynon OAT probe is mounted in the tailcone just above and behind the elevator spar cross-through cutout. The other is from my Rocky Mountain engine monitor and is mounted behind the rear spar just ahead of the flap LE. It's the slower of the two to respond to the change in temperature with altitude. Once I get to altitude, they will both indicate the same within about 5 minutes. They are out of the sun, exhaust, and slipstream, and so they give me the correct OAT. I always have to add about 3C-4C to my Garnmin's E6B TAS calculation to get Total Air Temperature, the sum of OAT and stagnation rise, which is 7 deg at 200 mph.
 
Under the stabilizer

As I mounted the EDC in the tail cone and the OAT connects to the EDC DB9 connector I mounted the OAT under the stabilizer just forward of the elevator linkage access panel. I have seen some people mount theirs in the access panel itself.
 
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