On Fri, 5 Sep 2008 07:55:15 -0700 (PDT),
wrote:

On Sep 5, 7:26*am, a wrote:
That's a very old patent! If you think about a propeller for low speed
flight, think about it as a rotating wing. You'll notice high
perfornance gliders have long slender wings, and the best props look a
lot like that, with an additional twist. Ducting helps, as do Q tips
on propeller edges, but I did read somewhere you gain as much
efficiency by increasing the propeller diameter as the q tip length.
Makes me wonder if the vortex decreasing terminations on wings might
be as well used just by increasing the wingspan by that amount.

That's exactly what Steve Wittman found 25(?) years ago on his Buick-
powered tailwind. He stuck some winglets on it, got some improvement,
then laid them down horizontally and found that they worked just as
well that way.

Dan

So is the vertical winglet

1) To increase wing length while
2) Looking cute

?