The superhero

We ignored The Incredibles, and we have a red Cape on the back of our boat:

Probably won't get caught in a jet engine. Probably.

The Cape takes us where we want to go. It's our self-steering mechanism for the boat. We rotate the red wing (using the 2 little ropes angling in from the left side of the photo) so the edge of the wing faces into the wind. In this picture, that's the left side of the wing. So, since we're looking backwards, the wind is coming from the starboard (right) side of the boat, and we are sailing on a beam reach. The bottom of this pipe and mechanism is the rudder, about 3 or 4 feet long and nearly a foot wide of hard plastic which is turned by the wing and steers the boat.

Always tie the rudder to the boat with the blue rope. If the primary attachment fails and we lose the rudder, then I have to actually steer, and that sucks.

In between the wing and the rudder is some pretty cool steam-punk mechanical action. Left/right motion in the wing moves a piston up and down, which moves an arm left and right (with a user-adjustable pivot, for different amounts of motion), which moves the angled bracket forward and back, which rotates the pipe that the rudder is attached to. So: since we've set the wing to face right into the wind, if the boat turns a little and now the wind pushes on one side of the wing, it tips down, which turns the rudder and moves the boat back on course.

The video uploading aspect of Blogger here seems to not be working, so you'll have to come down here and see it for yourself!