Posted for Gary Casey <glcasey@adelphia.net>:

I measured a 30% increase in yaw stability on my ES, but the potential
errors in the measurements might have ended up with the improvement being as
low as 25%. I would imagine the effect on the IV is the same since the side
profile is the same. The speed loss at cruise was 1.5%, higher than I would
like and higher than I think is necessary. I believe the "toe-in" is not
correct as the strakes are parallel and I doubt that the natural airflow in
that area is parallel to the bottom surface of the fuselage. I would have
rather had a single ventral fin rather than two, but then what would become
of the tie-down receptacle?

Gary Casey
ES N224SG

[We added a single ventral fin to Ted Noel's IVP... moved the tie down receptacle into the upper edge of the fin.  Attached photos show the submerged fitting and its location inside the fin.   The blue foam in photo 17 was used to protect the threaded area during the layup process... the fitting was made from a block of 3/8" thick steel (to match the 3/8" foam core in the fin) welded to a threaded rod that matched the threads in the original tie-down receptacle.  The original tie-down eye simply threads into that fitting from the side.  <Marv>         ]