Eric Greenwell wrote in message Compare the 113 sq ft, 15 M, 513 pound LS4 with the 82 sq ft, 12.6 M,
290 pound AC4 Russia: that's a 27% reduction in wing area and a 43%
reduction in weight! The fuselage is smaller, too, but not as much a
reduction as the wing. That seems to me a significant reduction in
finishing is possible, and also in the construction. Of course, an
obvious difference in materials cost (these are both fiberglass gliders).


What is it that economists always throw out... ceteris paribus...

I agree that if one started with a clean sheet of paper, then maybe
you can lop off a few pounds on the fuselage, change the planform,
etc. (though, having looked at the structure of some of these ships,
I'm not so sure I would want to fly them or land them off-field... but
I digress). Keeping everthing else equal, is the "best" use of
engineering to start with a shorter span as a design goal? Maybe it
is, as the weight savings on the spar and carry-through structure
allows for a good range of wingloading while bringing along the other
benefits mentioned elswhere (ease of assembly, transport, etc.)? Or,
maybe the design goal should be 40:1 performance at the lowest cost,
irrespective of span?