Christopher wrote:
The way it is done is to attach the feed at a point so many inches up
from where the coax would be grounded to the fuselage. Although the
fuselage is at ground potential where it connects to the battery and
negative lead for the avionics if you find the right spot to attach the
coax the feed will both be matched and radiation will occur on a
vertical member as if it were insulated from ground.

Here is a web page showing how it is done for the lower medium to high
frequency portions of the amateur radio band on a grounded tower, of
course, with an aircraft you would have more trouble to find a sweet
spot for loading into the frame than with a simple tower but I believe
it can be done at the tail, if you feed the lower portion of the tail
the remaining upper structure might be about the right length for
VHF-AM in the aircraft comm band:

http://www.qsl.net/w9rb/webdoc9.htm

If you are not an RF man with a through-line watt meter I wouldn't
expect this to be an easy task for someone new to radio or antennas,
but it could be done with a few hours work on a tube and rag aircraft
if you did it before it was covered.

I don't have any ham equipment, and this page has way more math than I
want to deal with. I think I'll just try wrapping 22" of copper tape
around a cheap aluminum pitot and see how it performs.

--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."