Performance optimization for a towed-cable system with attached wind sock

[article extract] Circularly towed-cable systems have been studied for several decades with the goal of stabilizing the cable tip in inertial space. When a cable is towed from an aircraft during a steady-banked turn, the cable end body tends to tow inside the path of the circle. As the cable length is increased and the cable end body weight to drag ratio is decreased, the cable tip approaches the center of the circle and ultimately appears to be nearly stationary when viewed from the inertial frame. The idea, proven successful in test flights, is to use this fundamental property of the system for pickup and delivery of payloads.