I don't think the wind or turbulence has something to do with penetration.
Penetration is the ability to proceed forward (fast) without much of a
(height) penalty. So to my idea for a glider it is typically L/D as a
function of speed beyond the speed for best L/D.
Especially the newer designs show quite flat polar curves for the higher
speeds, meaning that at the higher speeds L/D does not worsen very much.
Ideally L/D should not divert from best L/D for the higher speeds, i.e. a
completely flat polar curve coïnciding with the tangent from the origin of
the polar diagram. Then you would always fly with Vne and have the best
possible penetration for your glider. Another pilot would do the same, but
when the L/D for his glider is better he would penetrate better.

Karel, NL

"Stewart Kissel" schreef in
bericht ...
SNIP

I suppose it relates to how flat the polar curve is
above 100 kph

SNIP

Okay, I'll bite. If glider penetration describes the
ability of a ship to make progress into the wind without
falling out of the sky, is it soley a matter of looking
at the polar at the indicated airspeed? Intuition
tells me that is it, but an aeronautical engineer type
might make be look like a big dummy here.