Bill Daniels wrote:

If you fly at 10-12 pound wing loading in 15 knot thermals at 18000 feet,
it's superfluous.

Hello Bill:

You are correct, a glider designed to optimize Microlift conditions
would not be as well suited to cruising in these conditions. I, too,
enjoy flying very heavy wing loadings in the strongest reasonable
conditions. I am presently woking closely with Dr. Marsden on an
experimental 15m racer which will ballast to 13 psf normally, and have
designed a special system which would allow for 15 psf. This type of
flying is very exciting, and a worthwhile area to explore and push the
envelope. It is also ideally suited to pitch-based dynamic soaring
with high inertias, something that mostly captivates my attention
these days.

However, there are other fields of endeavor which are also worthwhile.
Have you ever stood on the ground in a 20 knot wind, and watched a
vulture fly from horizon to horizon at an altitude of 200' - never
once circling- against the wind? Ever wondered where is he getting
this energy? Or which of the lateral movements he is constantly making
are reactive and which ones are harvesting energy from random
turbulence? Some of us find this simple scenario at least as
interesting and exciting as the former one. At the very least, we
would like to understand it better and at the most, emulate or even
exceed it. This is one (and only one) of the things that Microlift
optimized designs are capable of doing which higher W/S approaches do
not. As it turns out, there are not simply quantitative differences
which are taking place at lower altitudes in the convecttive
environment but qualitative ones as well. The near-earth environment
does not simply contain thermal plumes which are lower than those
normally encountered in soaring flight at higher altitudes. There are
structural differences between the super-adiabatic layer, the next
mixed layer, and the higher normal soaring environment. Scale is
important here. The size of less organized structures which are not
yet thermal plumes in these lower environments is not well suited to a
12 psf W/S glider, or even a 6 spf one. Likewise, the magnitude of
stochastic but often widespread gusting and turbulence may comprise a
large fraction of the total flight energy of a low inertia glider,
whereas its nothing more than an annoyance in higher inertia systems.
With proper coordination and flight maneuvering, these smaller
turbulent events can impart repeating and substantial amounts of
energy to flight systems. However, the systems used must be matched to
the environment and it is not simply a function of wing loading. The
entrained air mass of the flying system, which is a function of not
only W/Sbut also mac and other factors must be considered.
Manueverability is very important, particularly rolling responses.

Until you have experienced this, it his hard to appreciate how it
could be as exciting as cruising at redline and 18k north of Tonopah,
while still 5k *under* cloudbase. However, I find it to be at least as
exciting. Not as high. Not as fast. But somehow just as amazing.

Not better. Not worse. Different, Bill. Something new to explore,
which is very, very old.

I guess it could be stated another way. I have never had the
opportunity to watch the launch of the Space Shuttle. I would like to.
However, if I had unlimited opportunity I suppose I would tire of it
after enough times.

I don't beilieve I will ever tire of watching vultures, or sea gulls,
or even butterflies doing their thing.

Still skeptical.

That's your prerogative. I would prescribe a little more time for
direct observation of the natural world, and a little less time trying
to view it as it rapidly recedes in your high speed rear-view mirror.

Best Regards,
Gary Osoba