Aircraft Wing Flap Noise-Reducing Fins

Two different modifications have been developed for the edges of aircraft wing flaps to reduce noise. Reactive Orthotropic Lattice Diffuser (ROLD) is a modification that consists of a honeycomb-like, interconnected structure added to the region of the flap that experiences the highest degree of sound-generating airflow instability. Flap Edge Noise Reduction Fins (FENoRFins) are modifications consisting of rigid fins on the edges of the aircraft flaps.