RV-3 Vent Location and Type

I searched the RV-3 forum and see that the last post on this subject was from 2014. It seems like there really wasn’t a consensus of what worked and what didn’t.

One option was the RV-10 backseat vent installed near the left knee and also on the right side just below the longeron. I could see where the 10 style vent would catch a bunch of air, but it seems a bit inelegant. I’m also not sure I want the inside workings near my right elbow/arm or near my left knee.

The other option was the twist style round vent made by Larry Vetterman and sold by Van’s as the LV-3. I really like the style and design of this vent and was very happy with the one I used on my Midget Mustang. I’m wondering if anyone has come up with a good place to install one or two of these vents in an RV-3.

The other old standby option would be some sort of NACA inlet with a SCAT hose directed to a twist on/off eyeball vent. Of course in an RV-3, space is in short supply so this could prove challenging.

I currently have fresh air coming off the back of the engine baffle on the right hand side of the engine. It provides a fair bit of flow, but the air seems to be heated about 20 degrees hotter than ambient. I’m an absolute weenie when it comes to heat so I need to find a cooler solution.

One option I’ve considered and that I’ll probably pursue if nobody offers a definitive solution is to essentially extend the inlet for my fresh air forward over the top of my right hand cylinders such that the fresh air intake is co-located with the engine air inlet. Of course my concern with this would be that I’ll dork up the flow over my cylinders and create cooling issues that are currently non-existent.

Thanks for all the help and support from this forum. I’ve owned Chuck’s Three for just shy of 11 months now and have accumulated right at 90 hours in it.

Some thoughts.

Rod, I have no silver bullet for you, but will share some thoughts:
1- The RV10 vent does work well on the right below the longeron. Looks OK outside but not elegant inside.
2- The RV4 gang (Smokey etal) convinced me to use NACA on the bottom side of the cheek cowls on my -4 project. They look cool, but would be a tough retro on riveted metal cheeks.
3- Regarding round vents/limited space, i built a slide gate for my pressurized cheek cowl from the front of the cowl,outside the Vans intake. Only problem was I made it 3/4? ID and it doesnt cool enough. However, consider slide gates inside the cheek cowl fuse wall like an oil cooler blocker. You can have big air in the cheeks and just dump it in under the panel from both sides. Can send pics if interested....Larry

Rv3 vent

My cool air comes from the middle of the rear baffle . Seems to work ok once I am in the air.
Steve Lenne
Rv3 b ( flying and loving it)

I?m a big fan of the RV-10 vents. I have two and they keep me cool(enough) on 100F days. Wouldn?t change a thing.

RWoodard said:

I searched the RV-3 forum and see that the last post on this subject was from 2014. It seems like there really wasn?t a consensus of what worked and what didn?t.

The other old standby option would be some sort of NACA inlet with a SCAT hose directed to a twist on/off eyeball vent. Of course in an RV-3, space is in short supply so this could prove challenging.

Click to expand...

I did the same searching for air vent info and came to the same conclusions, I purchased the RV 10 vents but decided I didn't like the trap door type operation (no doubt they work well though) so I went with kit supplied NACA vent and put it just below the RH cheek extension with an eyeball vent under the panel. I would preferred in the panel but have no space left there...The small cable in the bracket operates the cabin heat box and is not part of the vent. The "in cheek" installs look very slick and I considered doing that but found that when the cheek extensions were fitted and drilled they are under a certain amount of spring back tension and I wasn't sure how cutting a hole for the vent would go. Guess I could have made glass extensions and they probably would have fitted a whole lot better but I like aluminum. Anyway it's not flying yet so I don't know how effective this setup will be but I think you could fit one into a flying plane without too much trouble.

Below cheeks on my -4

I put a NACA below the cheek on both left and right sides of my -4, which likely has the same airflow characteristics as the -3. I did not put the flex ducts and vents as most do, but rather bonded the eyeball directly on the back of the duct neck...mostly because I didnt want to take up panel space or knee room. I simply each down by my shin and adjust flow. I get tons of airflow, and if aimed up at my face, my mic will activate. I installed the NACA plastic vents using pro-seal and 6 3/32" soft "A" rivets lightly driven, which are almost undetectable. Very clean simple install. I used aluminum Boeing cockpit eyeball vents with the mounting tabs cut off which are very tight sealing for winter ops.

Thanks to everyone for the replies.

I spoke with a very accomplished builder this morning and he suggested that I gather a little data before I start looking for solutions to a problem that may or may not exist.

I?m going to place a temp probe at the eyeball vents currently installed in either side of my panel. I?ll also try removing the scat tubing between the heat muff and the mixing valve mounted on the engine side of my firewall.

I keep saying that my problem is with temperature and not volume of air, but the more I think about it, I may be completely wrong. Many (most) of my flights are not far enough to justify climbing to really cool air. I?m fine in my Citabria because I fly around with the window open and the 110mph breeze makes even 90 degrees OAT tolerable. With the bubble canopy in my RV-3, I?m not sure it?s even *possible* to flow enough air to make 90 degrees tolerable.

The short version: I need to define the problem before I spend a lot of time on a solution!

[Does anybody make an air conditioning unit for an RV-3? ]

Sun sheild

Aluminized bubble pack insulation from home improvement store makes a huge difference. Just use suction cups from Hobby Lobby to secure a piece in the canopy top and remove it for winter ops.

Larry DeCamp said:

Aluminized bubble pack insulation from home improvement store makes a huge difference. Just use suction cups from Hobby Lobby to secure a piece in the canopy top and remove it for winter ops.

Click to expand...

That’s a pretty good idea. Have you had any problems or do you have any concerns with focusing the sun/heat and melting the plexi or causing a soft sport or distortion? I’ve heard horror stories of how polished airplanes can harm plastic airplanes when parked in close proximity. I wouldn’t want to screw up my canopy.

Thanks again for a great suggestion.

Concern for heat in canopy

Rod,
This is my third summer and have seen no ill affects on the canopy. I have some pics if desired but its pretty simple. Cut the shape you like for visibility and use the little stems on the suction cups to secure the edges. I am using 5 or 6 3/4? cups.

I?ll give it a whirl. I seem to be at Home Depot several times a week these days so I?ll put some of that shiny bubble insulation on my list!