"David Bingham" wrote in message
...
Hi Gang
For approximately 30 years the performance of gliders has hardly
advanced at all and yet we now have the tools (computer programs) and
much stronger materials (carbon composites) to surely advance the
state of the art of gliders. Has this happened? Yes there are marginal
improvements but so small. What's the reason for this slowdown in
innovation? I believe in no small part it is due to the sailplane
classes. With the establishing of the classes that are so rigid and,
in my mind, so restrictive, innovation has suffered.

(Snip------)

Yep.

The first class, (Standard Class) was intended to reduce glider costs by
virtually eliminating innovation which, it was felt at the time, was leading
to ever larger and more expensive gliders.

The flap enthusiasts insisted on splitting off as the 15 meter class.

Both classes became successful at the expense of the open class where carbon
composites make the most difference. In a 15 meter design, the main benefit
of carbon is lighter wings for easier assembly.

Manufacturers were forced to produce special gliders for two similar 15
meter classes. Designers were forced by the same class rules to pursue ever
more expensive ways to improve performance such as extremely smooth
surfaces. They wound up producing expensive gliders anyway because of short
production runs.

It's interesting to speculate what would have happened if the competition
organizations had resisted creating competition classes. Innovation would
have run free. It's even possible that large span, ultra-high performance
gliders would be priced the same as 15 meter gliders are today because of
much larger production runs.

I've heard interesting speculation that there's a 'natural best span' around
18 - 20 meters that would be the best compromise for all conditions. If the
market had settled on that, we might have had innovation AND low costs.
We'll never know.

Bill Daniels

p.s. I recently listened as a 'pundit' was holding forth on the reasons for
the demise of the open class. He was saying that they were just too hard to
rig. A short distance behind him an ASH-25 owner was whistling softly to
himself as he rigged solo using simple aids.