Posted for N301ES <lancair@ustek.com>:

 If the aircraft is non-conductive E-glass composite then in-or-out would make
no difference because electrically the composite is not there.  If the
aircraft is conductive aluminum then in-or-out would make no difference
because electrically the inside is the outside.   Graphite composites are
somewhat conductive and this bears some research.  Ryan of Stormscope and TCAD
fame suggested to me that Lancair builders try an Al sheet on the inside of
the fuselage, be the plane graphite of glass.
 
 Robert M. Simon,  ES-P N301ES