Wings

 I've been slowly working on a wing, for my own version of the AC 72 class.  I probably won't race it in San Francisco this summer because it doesn't match up to the standards, but I'd like to make a small hydrofoiling remote control catamaran for sailing around. 
To that end I have been making a wing.  The main spar is a fiberglass piece of pole saw pole, and then I made mahogany foils and put a cedar leading edge on it.  I still have to put the skin on, but that is a careful operation, so I've been leaving that till later, when the other parts are finished.
The wing will be unstayed, so it attaches with a bearing (so it can pivot).   The wing is 7 ft tall, and the bearings on the bottom are only 6 inches apart, so there is a fair amount of load on the beams, but I'm getting it all figured out. 
The most interesting feature of this boat will be that there is no main sheet.  I intend to control the wing via a "tail" that makes the whole thing look like an airplane got stuck to the boat, so the tail controls the "angle of attack" of the wing-the angle to the wind-and if the wind shifts, the wing shifts with it, keeping a constant angle of attack.  To depower you just put the tail into straight ahead mode and the wing points into the wind.  This kind of set-up is used in a few other boats, and on a few autonomous boats, because it is easy to control.  You never have to ease the sheet in a puff, it eases for you.

In other news, I've made yet another sailing video, of a trimaran.  Its quick and stable and I want one.