The geometric structure of birds’ wings, especially edges and wingtips, plays an important role in improving flight conditions. In order to investigate the changes in flow physics caused by the corrugated trailing edge and wingtip slots, a three-dimensional numerical simulation of the eagle wing with corrugated trailing edge and flapping motion was carried out in forward flight. First, lift and drag forces were compared between numerical and experimental results, showing acceptable agreement. As key parameters, the lift force, thrust force, and lift-to-drag ratio were compared between the modified and the baseline wings. The results revealed that using the modified wing led to the improvement of the lift force by 14% on average compared to the baseline wing; with a maximum increase of 45%. Furthermore, the thrust force of the modified eagle wing was higher than that of the baseline wing by up to 21%. According to the analysis of the flow physics in the present simulation, the pressure difference between the upper and lower surface of the modified eagle wing was larger compared to the baseline wing, and the highest effect on the flow physics was exerted by wingtip slots. Also, the behavior of vortices at different sections across the wing length revealed that the interaction between the wingtip slots led to flow deviation in this region, an increase in the flow kinetic energy in the boundary layer, and a decrease in the flow separation and vortices separated from the wingtip. Further, it caused the separated vortices from the wingtip to change from the concentrated state to smaller vortices with less strength, which reduced the induced drag and enhanced aerodynamic coefficients

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