This paper describes a series of experiments that enabled a flight demonstration of roll-control withoutmoving control surfaces. That goal was achieved using a wing with a part span Glauert type airfoil,characterized by an upper surface boundary layer separation from the two thirds chord location at allincidence angles. The flow over that region was proportionally controlled using zero-mass-flux unsteadyPiezo-fluidic actuators. The control was applied to one wing at a time, resulting in gradual suppressionof the boundary layer separation, increased lift and reduced drag, leading to a coordinated turningmotion of the small electric drone. The extensive collaborative and multidisciplinary study, starting fromactuator adaptation, airfoil integration and 2D wind tunnel tests led to the selection of a configuration forthe flight demonstrator. Further development of a light-weight wing, Piezo-fluidic actuators along with acompact, light-weight, energy-efficient electronic drive-system was followed by full-scale wind tunneltests and three successful flight-tests. It was flight-demonstrated that active flow control (AFC) caninduce roll moments that are sufficient to control the vehicle flight path during cruise as well as duringlanding. These were, to the best of our knowledge, first time achievements that should pave the way tofurther integration of AFC methods in flight vehicles for hinge-less flight attitude and flight path controlas well as improved performance and increased reliability with lower observability.
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