Define penetration.

Well, since you brought it up, the stronger the tailwind, the more
important your minimum sink rate becomes in establishing the greatest
possible distance over the ground. With a headwind, you are turning
the speed ring clockwise... speeding up. With a tailwind,
counterclockwise... slowing down. So to answer your question, NO, you
don't "penetrate" downwind. High speed glide angle is less important
than the total time you can remain aloft, allowing the wind to carry
you along.

Withdrawing? Only if soaring is a particularly sensual experience.
Hmmm, penetrate rapidly, withdraw slowly. Not a bad perscription all
the way around.

Drifting might be a better label, though it too is loaded with
connotations.


"whbush" wrote in message ...
So you can't penetrate downwind? So going down wind is withdrawing?
"Chris OCallaghan" wrote in message
m...
I'll give it a try....

Penetration: a measure of sailplane performance as a function of Lift,
Drag, and Airspeed such that increase in drag is disproportionately
small compared to increasing airspeed throughout the sailplane's speed
range.

Since penetration is most often used to describe a sailplane's ability
to make progress against a head wind, a "penetration factor" of a
sailplane could be measured by establishing L/D at speeds of 60, 80,
and 100 knots, or, conversely, at some fixed rate of sink. The 300
feet per minute sink rate speed has been used as a de facto
penetration factor in the past. The higher the measured airspeed at
-300ft/min, the better the penetration.