Depending on how adventurous (and mathematically included) you are,
you might consider generating your own circular calculator. (Stocker
glide computer). Reichmann has a fair description in his classic
Cross-Country Soaring. I presented a paper at the 1991 OSTIV that went
into some more detail on the construction and added an HP Basic
program to generate the overlays for a given glide polar.

While the HP Basic is long out of date, the principles remain the
same.

You can find the paper and program info on Guenther Eichhorn's Soaring
Server,

http://soaring.aerobatics.ws/SOARING/ssa_programs.html

unde the title Ostiv91.zip, down near the bottom of the page.

Bob

On 6 Nov 2004 05:16:39 -0800, (snaproll59)
wrote:

Does anybody have a clue where I could get a "Whiz Wheel" for a
Standard Class (ASW 19)? I can't believe that everybody has absolute
faith in the reliability of their electronic glide computers. Last
week my computer lost its 3-D GPS fix and I was forced to use my
wits...not a very useful tool. I've contacted all the usual suspects
in the US and asked the British Gliding Association for ideas. Whiz
Wheels seemed to have gone the way of my wing-mate the Dodo bird. TIA
Gene