Autorotating helicopters, based on the shape of maple seeds, are made from paper. 1.Make copies of the maple seed pattern and derivatives on blank paper. Cut out each pattern. 4.If the design fails to autorotate, adjust the position of the paper clip slightly. 5.Experiment with different designs of your own making.
Maple seeds are superb autorotating helicopters.
They begin rotating almost from the moment they are released from the tree. The center of mass of the seed is shifted well to one end while its center of lift is approximately in the middle. In a complicated process, the forces at work as the seed falls combine to begin a circular rotation of the seed about its center of mass. The rotation actually inscribes a cone around the axis of fall. A blade with minimal lift properties will inscribe a steep-side cone while a blade with strong lift properties will inscribe a very flattened cone.