when we addressed the wing, we started with a complicated rule, to limit what a designer could do. We added more and more pieces as we thought of more and more outcomes, and we came to a point where it was so complicated—and it was still going to be hard to control, because the more rules you write the more loopholes you create – that we reverted to a simple principle. Limit the area very accurately, and make it a game of efficiency.
But it's not from Rutan at all; it's an excerpt from Wings, the Next Generation, an article discussing the sailboats to be used in next summer's America's Cup qualification matches.
Now, everybody knows that sails, and airplane wings, actually have very much in common, so it really isn't surprising that this sounds like aerospace design. However, as Paul Cayard notes in the article, the wings on a competition sailboat have a few special constraints:
the America’s Cup rules don’t allow stored power, so two of our eleven guys—we think, two—will be grinding a primary winch all the race long. Not to trim, but to maintain pressure in the hydraulic tank so that any time someone wants to open a hydraulic valve to trim the wing, there will be pressure to make that happen.
It will be fascinating to see these boats in person, racing on the bay, but I'm glad I won't have to be one of those grinders!