On Feb 1, 2:06*pm, (Michel Talon) wrote:
Bob Kuykendall wrote:
No, not true. As I've written elsewhere the manufacturing cost seems
to scale exponentially with span.

I don't pretend to be as knowledgeable as you about gliders, but
i know that exp(15/14) is not very different from 15/14.

One has to chase economies elsewhere.

One must chase economies everywhere.

Mostly in the hourly cost of manpower, e.g. by building in China,
not paying horrendous fees to some university departments to do the
computations when it is certainly possible to get them for free,
and so on. Probably everything else is negligible.

--

Michel TALON

Not so fast, if you want to argue with pseudo-math lets get it right.
15/14 is ~1.071, e^1.071 is 2.91 which *is* very different. But what
you should be asking is what is e^15/e^14 which is a ratio of 2.72,
since Bob said the cost scales exponentially with span, not
exponentially with the span ratio. Not that 2.7 is far from 2.9, but
at different span ratios the difference in calculations becomes, ah
exponential. Not that this means anything, since Bob was just likely
making a point with a hyperbole.

I'm curious who pays "horrendous fees" to universities. My impression
is many European manufactures get pretty sweet deals via relationships
with different University research groups and Akafliegs.


Darryl