[Geeman]

As the title says, I am about to install an OAT probe in a finished RV-6. The recommended location is outside the arc of the prop. That basically leaves the wing.

What is the best way to run a wire in a finished wing without conduit.

Or can I just install it in the tail somewhere furthest from the prop arc?

 

[Neal@F14]

Put it somewhere where it will be well out of reach of any heat coming off the engine. I would not put it on the belly under the tail, since it still may pick up some hot exhaust or hot air there. The builder of my RV-6 put the probe inside the NACA duct on the right side of the fuselage. It picks up so much heat off the engine it's worthless. (it thinks it's 70 degrees when it's 30-40 outside )

I intend to relocate mine to near one of the inspection covers under the right wing, and intent to run the wire alongside the existing nav/strobe light wiring which is run thru a series of snap grommets in each rib. It'll be a little work to fish it thru them all, and I might even have to disconnect the nav light's tefzel wire from the wingtip end, and tie a pull string to it and pull it back into the floor under the right seat, then attach the new temp probe wire and nav light wire to the pull string and pull them back thru series of snap grommets inside the wing together.

 

[JonJay]

Lot's of good stuff in the archives. I would do a search.

However, I have one placed in the wing root fairing, pilot side, under the wing and one, passenger side, in the first bay of the HS.
They work well there.

 

[airguy]

Many people have retrofitted them into the middle of one of the access plates on the underside of the wing.

 

[bhester]

I've got two

One is on an inboard inspection panel on the RH wing and the other is on the inspection panel under the LH Horizontal stab. Both spots work great!

 

[pa38112]

I just installed one on Saturday and flew it today (RV6A). I put it inside the NASA duct on the pilot's side. It seemed to work fine there. I see another poster said that his does not work there, but I don't know why. It should not be getting any engine heat and should have lots of clean air flow. I put mine back as far as I could to eliminte any effect from the pressure drop. I located it in the round transition 1/4" from the end.

 

[Geeman]

I just installed one on Saturday and flew it today (RV6A). I put it inside the NASA duct on the pilot's side. It seemed to work fine there. I see another poster said that his does not work there, but I don't know why. It should not be getting any engine heat and should have lots of clean air flow. I put mine back as far as I could to eliminte any effect from the pressure drop. I located it in the round transition 1/4" from the end.

That would definately be the easist place to put it. I may try it there first. Problem is, how do you actually know it is accurate. I geuss flying low compare to local weather temp.

 

[Rosie]

I just installed one on Saturday and flew it today (RV6A). I put it inside the NASA duct on the pilot's side. It seemed to work fine there. I see another poster said that his does not work there, but I don't know why. It should not be getting any engine heat and should have lots of clean air flow. I put mine back as far as I could to eliminte any effect from the pressure drop. I located it in the round transition 1/4" from the end.

This is also where mine is and no problems after 3,500+ hours Rosie

 

[RV8iator]

Another Reference

I had one in the NACA vent on the left fuse side on my 8 and it read exact temperatures perfectly, -- until I started my engine-- then it was always 10-15 degrees warmer than actual.

I have one now in the right wing outboard inspection cover and another in the right wing NACA vent and they read withing 2 degrees of each other, engine on or off

 

[JonJay]

I had one in the NACA vent on the left fuse side on my 8 and it read exact temperatures perfectly, -- until I started my engine-- then it was always 10-15 degrees warmer than actual.
QUOTE]

Same experience here. I am not sure why some work in this location and others do not. Maybe it is the type of sensor, the mount, I don't know.

 

[pa38112]

It could be electrical interferiance, or it could be exhaust gas wraping up and into the duct, but that would not be a factor once flying - just on the ground. There is too much air flow when flying for the engine or prop to change the air tempature entering the NASA duct.

 

[Neal@F14]

I had one in the NACA vent on the left fuse side on my 8 and it read exact temperatures perfectly, -- until I started my engine-- then it was always 10-15 degrees warmer than actual.

Same here. Before I ever start the engine, the temp reads good. Immediately after I start the engine it reads good too... until the engine starts to warm up then the temps begin to climb. I can watch this happen as I'm waiting for the engine to warm up prior to runup and takeoff. Both warm air from the exhaust and warm air from the cowl exit, plus maybe even a little warm air leakage from the upper-to-lower cowl piano hinge seam might all be culprits. Either way, the probe is definitely in a bad location on my RV-6.