It took me a while to picture this without pictures but it is quite ingenious, if I pictured it right. I can see how it kicks up in one direction but fail to see how it does in the other direction, unless the whole axle kicks up.
Rob wrote:
"It has a leeboard and a half round rudder in a case at each end. The half round rotates around a pin across the bottom of the case, which is set at 15 degrees off fore and aft. When it is up, there is nothing under the boat. When one is rotated up to 90 degrees, it protrudes beneath the boat at an angle and turns the boat. The other end turns it the other way. I will probably end up with 2 in each end as the bow is often airborne. Advantages are that nothing sticks below the hull except when you want to turn, it kicks up if you hit something and is pretty easy to build. Downside it you need 2, probably 5 cases."
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