A conventional aircraft that has been equipped with some newly designed internal or external components for in-flight testing of those components. Thor-Delta Two stage rocket booster using a Thor 1st stage and a Delta 2nd stage. Using three parallel components to accomplish a single function, with automatic deselection of any faulty component. An array of short segments of yarn or string taped to an aerodynamic surface to allow airflow characteristics to be observed or photographed. The angle of the aft control surfaces relative to the flight direction.
Large angles produce shuttlecock-like stability.