In the near stall regime, when the airflow over a wing is partially separated, the shedding of coherent structures can result in large unsteady aerodynamic loads. Under such conditions, high aspect ratio wings such as found on modern composite airplanes, will experience some degree of structural motion normal to the chord line. Simulations and experiments for a chord-based Reynolds number of Re=200k were carried out for a wing section with a X-56A airfoil to investigate the effect of a harmonic heaving/plunging motion on the unsteady aerodynamics. The reduced frequency of the structural motion was in the range 0.35展开▼