This is how it works:=
Off the transom is hung on a light weight rudder hinge, a piece of wood hung
vertical with handle at the top into the dingy, used to swing back and
forth, like an oar.
The bottom end of the vertical wood that's in the water, is fixed a flexible
conveyor belt type material, many flexible materials can be used, this
drives the boat forward when the handle at the top is pulled back and fore.
the length is atleast 24 inches, or longer and 6 inches wide or more.
I feel that it could also control direction, but not as good as a rudder .
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