In this research, the rotary-wing blade with an on-bladeTrailing-Edge-Flap (TEF) is considered in hover. The wake induced effectis included. Peters’ generalized deformable blade aerodynamic theory isused for the formulation of the TEF model on the rotor blade. TheGalerkin’s method is employed to solve the coupled system. This studyexamined the effects that changing the TEF position and chord-wise size onthe physical performance of this system. This research also found thatchanging the TEF’s span-wise hinging position, the lift and torsionalmoment generated by the blade increases as the value of the TEF span-wisehinging position increases. Several nonlinear dynamics on the bladeassociated with the TEF effects were discovered in this research as well.The methodology of this paper and the results derived in this study will beof use to both the helicopters and wind turbine blades.