Transponder Antenna Ground Planes

A friend forwarded the following study ... has anyone tested
Transponder Antenna output on a graphite ship without an additional
ground plan?

Title:
Performance of graphite epoxy as an antenna ground plane
Authors:
Erickson, J. E.; Graham, O. D.
Affiliation:
Air Force Academy, CO.
Publication:
Final Report Air Force Academy, CO.
Publication Date:
08/1978
Category:
Communications and Radar
Origin:
STI
NASA/STI Keywords:
AIRCRAFT ANTENNAS, GRAPHITE-EPOXY COMPOSITES, GROUND SUPPORT EQUIPMENT,
PLATES, ANTENNA RADIATION PATTERNS, DIPOLE ANTENNAS, IMPEDANCE MEASUREMENT,
MONOPOLE ANTENNAS
Bibl iographic Code:
1978aifo.reptQ....E

Abstract
This final report describes work undertaken by members of the Department of
Electrical Engineering at the USAF Academy, Colorado for the Post Doctoral
Program/Rome Air Development Center/Griffiss AFB, N.Y. This effort involved
a study of graphite epoxy composite material as an antenna ground plane at
the frequencies of 370 and 837 MHz. Five by five foot sheets of graphite
epoxy were provided by the Composites Laboratory of the Air Force Flight
Dynamics Laboratory at Wright-Patterson AFB. Antenna impedance and antenna
pattern measurements were made using these graphite epoxy sheets and also an
identically sized sheet of aluminum. These measurements were made with both
monopole and dipole antennas and also with a UHF blade antenna from an F4
aircraft. Results show that the 50 ply sheet of graphite epoxy behaves
identically with an aluminum ground plane when used with a monopole or
dipole receiving antenna at 370 and 837 MHz