OAT probe- which wing panel?

pilot2512 · #1 04-07-2019, 12:51 PM

I plan to install my OAT probe in my left wing. 3 inspection panels to choose from. Which one? Most inboard, shorter wire run but may be to close to exhaust stream. Middle panel, further away from exhaust stream and nothing else there. Outmost panel, already running wires to pitot probe but might it interfere with the high current pitot heat, also a much longer wire run. Decisions, decisions. Anybody have issues in any of those positions? TIA.

Jay

Bevan · #2 04-07-2019, 12:57 PM

Mines on first inspection panel and works good. I can?t see how there would be any engine heat there.

Bevan
RV7A

Jpm757 · #3 04-07-2019, 01:22 PM

I have dual probes, one on each inboard panel, works great.

N941WR · #4 04-07-2019, 02:02 PM

I mounted mine on the he last bulkhead, under the empennage fairing. Works great and isn't out where it is going to get knocked off.

BillL · #5 04-07-2019, 02:57 PM

The basic rule of "not within the prop swing" seems to work. I installed mine in the left wing root and all seemed well until I was doing leaning studies in Phase I. Oddly I found that the temp changed with EGT, which also greatly affected cabin heat.

I concluded air goes in strange places and put a thermocouple under the wing at the first inspection plate. It remained stable compared to the wing root, so I moved it to the first inspection plate on the left wing. I don't like it there, but it works and got weary of testing.

I am sure 3 kts are lost to this rod sticking in the wind.

N941WR · #6 04-07-2019, 04:04 PM

Quote:

Originally Posted by BillL

The basic rule of "not within the prop swing" seems to work. I installed mine in the left wing root and all seemed well until I was doing leaning studies in Phase I. Oddly I found that the temp changed with EGT, which also greatly affected cabin heat.

I concluded air goes in strange places and put a thermocouple under the wing at the first inspection plate. It remained stable compared to the wing root, so I moved it to the first inspection plate on the left wing. I don't like it there, but it works and got weary of testing.

I am sure 3 kts are lost to this rod sticking in the wind.

I have never heard that they shouldn't be within the prop arc. It is not like they have evaporative cooling, like your skin does.

My goal was to place it where it won't get knocked off when cleaning the plane or snagged by my dog's collar.

Probably the worse places I have seen are in the NACA vent or on the belly, just behind the firewall.

rolivi · #7 04-07-2019, 05:56 PM

Here's how I did mine.

BillL · #8 04-07-2019, 08:04 PM

Quote:

Originally Posted by N941WR

I have never heard that they shouldn't be within the prop arc. It is not like they have evaporative cooling, like your skin does.

Well, it is most likely place to collect clean (thermally uncontaminated) air, and I don't wear dog collars anymore.

I just got some more thermocouple wire, I'll run one back to the HS and see what it reads.

I am not sure where that came from, maybe in the Garmin Manual?

Hornet2008 · #9 04-08-2019, 02:02 AM

Mine is under the right horizontal stab. Works fine and a tail wheel. Usually land on grass.

Pilot135pd · #10 04-08-2019, 09:18 AM

To all who say it works fine wherever you installed it, does that mean it stays there when you fly and hasn't fallen off or does it mean the prop wash or other wind factors aren't changing your temperature readings?

How do you know it's working fine AND giving you the correct temperature reading?