Protecting avionics in RV-4

blackbeard10 · #1 06-10-2013, 08:31 AM

Protecting expensive avionics from rain in an RV4.
The RV4 avionics are covered by a short fuselage top skin that runs from the
back of the to cowl to the instrument panel. There are nut plated screws fastening this the fuselage forward, aft and on the sides. I am using a siicone window glazing product that comes in many colors. (I am using gray) to seal this skin as much as possible. BUT there still are the screw holes and the air pressures at cruise that wants to lift things up.

What are others doing to protect electronics without compromising cooling?

bkthomps · #2 06-10-2013, 08:35 AM

i put mine in a hangar'

all jokes aside, don't seal that skin up, you'll be taking it on and off a lot, i have no sealant on those nutplates/screws and no issues.

fixnflyguy · #3 06-10-2013, 08:43 AM

I "sealed" mine simply using a thin foam gasket at FWD and AFT end, and havent had any real leak issues at all, but I dont fly in a lot of rain,and my plane is hangared. The canopy cover I have covers the seam where the canopy opens, and does fine for rain when tied down on overnights. I also covered the inside with fiberglass insulation (sealed aircraft type) which keeps the heat from cooking stuff on sunny days. I avoided any type sealant, as I access that area occasionally to get behind the panel, a feature that is unque and very handy to the -4.

blackbeard10 · #4 06-10-2013, 08:45 AM

Refer to first post. The silicone glazing was applied to fuselage surface. Waxed Saran wrap was placed on the opposing skinsurface so the skin is easily removable (fifty some screws!)

Neal@F14 · #5 06-10-2013, 09:20 AM

Never put silicone-based RTV or window caulk on any piece of aircraft aluminum that you might expect to have to repaint anytime in the future.

If you are convinced that you just have to put some kind of waterproofing sealant there, then use something that won't "glue the panel shut" and that you can still remove and clean off if necessary. EZ Turn grease (FuelLube) would probably work well, since it's waterproof, can be cleaned off with MEK and lacquer thinner, and doesn't melt until it gets over 190 degrees F.