A flow control device is disclosed including a flow control surface over which fluid is designed to flow in a predetermined direction. Vortex generators are associated with the flow control surface. Each respective vortex generator has a pivot axis that forms an acute angle with respect to the predetermined direction and is capable of being positioned in both of an extended state, in which the respective vortex generators function to create a swirling fluid flow, and a retracted state, in which the respective vortex generators are pivoted via the pivot axis so as to lie adjacent to the flow control surface. An actuator is associated with each of the vortex generators, each actuator adapted to position the associated vortex generator between the extended and retracted states. The flow control device is disclosed to be used in tiltrotor vehicles.