The main idea of long wings is to reduce the relative part of the wingtip
vortexes in the total amount of the drag.
Having 4 vortexes instead of 2 certainly doesn't help.


"Jono Richards" wrote in
message ...
A thought came to me the other day...

Now, I have never seen a bi-wing glider, but was thinking,
could a bi-wing glider of, say 15m wingspan, effectively
have 30m performace?

This is probably a stupid uneducated question, and
I would imagine that it hasnt been done because it
wouldnt work! But its certainly something I am interested
in.

Think of it...a bi-wing ETA giving a total of 60m performance!


JR