A note to the mechanical principle in knotting with fly-stone

A rope can be knotted on a distant pole by using a sandbag connected at its end. Spin the rope to enhance the sandbag’s velocity and throw it out; pull the rope tightly to induce the sandbag rotating downward when it flies over the pole; shorten the rotating radius of the sandbag when it closes to the lowest point with increased velocity from the gravity potential energy. The sandbag’s velocity increases with the radius shortening on the momentum equilibrium, and then the rope may mound on the pole. The friction between the rope and pole can provide a great magnitude of load capacity.