Ray Clegg wrote:

Jerzy

Martin Hollman is the designer of both the two and four seat KIS.

PFA wrote  to him in July 2000 questioning whether there was an error in the
structural design of the centre section spar at BL 46 where there are 28
plies according to the analysis. Martin Hollman replied saying PFA were
correct and  a stress check on the shear strength of the center spar at BL
46 showed negative margins of safety. The modification he suggested was to
remove the eight ply pad at BL 46 and replace with 12 plies from the tip of
the spar to BL 22 to increase the margin of safety to a positive value.

Martin Hollman sent a copy of that letter to Rich.

PFA were still not satisfied that Martin Hollmans modification was adequate
so asked me to wrap the twelve layers onto the upper and lower spar caps. I
did this and at my suggestion continued the twelve new layers onto the
fuselage so that there was no abrupt termination at BL22.  PFA also asked
for four additional plies on the front face of the spar.

I am not qualified to know whether the modification is essential I can only
do what I am told. I do know that Vance does not believe there is a problem
with the spar

Ray

{#} ----------------------------------------------------+[ kisbuilders ]+---

 
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