50+:1 15m sailplanes

"Jim Phoenix" wrote in message
om...
Interesting.

I recall a technical discussion a long time ago asking whether there
was a
"natural best wingspan" imposed by the nature of soaring weather. The
question was this: "Ignoring competition classes, is there a single
best
wingspan that is suited for the widest range of soaring conditions? The
answers converged around 18 meters. Larger spans were considered too
slow
in strong conditions and smaller spans suffered in weak conditions.
It's
interesting that the "most cost effective wingspan" is about the same.

This makes me wonder if eventually the 18 meter class will become
dominant.
It also makes me wonder if the selection of 15 meters for the two most
popular classes was an error.

Bill Daniels

If this was true, why do the 25m gliders win the Open class
competitions? Why aren't the LS8-18's and V2C's etc. cleaning up on
the ASH-25's?

Maybe I'm missing something... but maybe not - didn't a Ventus win
open in SA recently (I could be mistaken).

Jim

Hi, Jim.

I like big gliders too.

I don't think these guys were talking about existing gliders. They were
just asking, if you designed a glider for speed, what wingspan would you
choose, ignoring all else? The consensus was 18 meters.

With carbon rods, you could probably build a 60 meter glider but would it go
fast? Probably not. There is likely to be an upper limit imposed by
soarable meteorological conditions. There may also be a sweet spot
somewhere around 18 meters. If that turned out to be the case, and it was
also the most "cost effective span", the 18 meter class would be a "natural
class". I find that a pleasing thought.

Bill Daniels
Nimbus 2C