I'm building a carbon fiber airplane and understand that the carbon is too
opaque to radio signals to use antennas inside the carbon. (The wing tips
are E-Glass and come with navigation antennas already installed.) For
communication, marker beacon, and transponder antennas, I'm wondering why I
can't use a foil tape antenna kit to stick foil tape to the outside of the
fuselage skin somewhere on the belly and then cover it with a layer of
E-Glass to protect it? I could use the carbon as the ground plane or build
one inside the fuselage, if the carbon isn't enough.

I heard from an expert that applying the foil directly to the electrically
conductive carbon would be just as bad as applying it directly to aluminum.
That makes sense, so how about I put a nonconductive layer of something
(E-Glass?) between the foil and the carbon?

Thanks,