RV-4 Ventilation

[szicree]

Well, I've finally gotta sort out a fresh air ventilation system on my -4 and am hoping to get some ideas from those who have gone before. I'm leaning towards a NACA duct below each cheek (the plane's, not mine) but would love to hear about other ideas. I'm not willing to cut into the wing and like simple.

 

[CraigH@KRPH]

Ventilation is great in mine. It stays cool in flight even when it's 90F plus in the Texas summer. I've got 4 of the circular flip vents around the canopy (2 in front, 2 in back), 2 NACA vents (one below each cheek) and another vent coming from the air inlet in the nose. Total of 7 vents, and it stays plenty cool.

 

[pierre smith]

Fire risk

Hi Deven/guys,
We installed a naca inlet below the right cheek on our -4 and it works well for the pilot. Rear seat hasn't been addressed yet.

I personally worry about fire being ducted to the cockpit if you come off the rear baffles. I wonder if the CHT's rise as a result of the loss of pressure since you're rerouting the air.

Any thoughts?

 

[randylervold]

Howdy Steve,
The 4 I bought came out of California and has very good ventilation. No cabin heat yet (Colorado winter almost here) but anyway there are 2, two inch inlets that come off the back of the baffle and feed 2 eyball vents in the cabin. I was skeptical before flying it but now I like it. No messing up the exterior of the aircraft and they cool very well.

I used this method in my RV-3B, but with only one tube... works great.

 

[John_RV4]

back of the baffle, but...

I also have the back of the baffle setup and yes it can blow a hurricane into the cockpit. No significant effect on cht that I have ever observed but I haven't tested for that specifically.

I also share the engine fire concern. I don't plan to use this setup on my own project for that reason. Also, I think in another post, somebody mentioned that this setup would not be approved in Canada for the fire reason.

John

 

[Warren Moore]

I have one naca vent below the right cheek with a scat tube to an eyeball vent on the panel, which works ok...I also put a van's naca inlet on the bottom of the right wing, routed a scat tube to the rear seat.....works GREAT! (like on the 8's). have since put a tee in the rear seat scat tube and routed a 2 inch scat tube to a eye ball vent in the front by the fuel selector...using the routing for rear seat heat in the plans (so no rear seat heat anymore). When solo I reach back, close the rear seat vent and have it all come up front...so I get blasted in the stomach and face...works really well....I live in Houston!