Design rules of thumb.
Folks,
Just a general comment pertaining to
this
Rule of Thumb thing.
Design rules of thumb are what they
say they are, general rules
that generally applyin fairly standard conditions.
For a designer they are a start point,
which
they may or may not use to
set up some general parameters before
tightening
the design spiral on a particular
boat.
By hedging the fuzzy boundaries of
such
rulesany good
designer can beat them.
When designing a boat for specialist purposes or
conditions,
any good designer will discard them.
This is why they are not laws or
axioms.
An example of such a RoT is
"Sail Area (Cruising sailboat)" = 2.5 x (wetted
surface area).
Very general, a start point for preliminary
design.
Some cruisers wind up 2, some as high as
4.
Jeff Gilbert.