A nonlinear simulation strategy is presented for low-speed flexible aircraft with flared hinged wings. A multibody solver based on geometrically exact composite beams is coupled with unsteady vortex lattice aerodynamics in the time domain. The structural model is first verified against simulations on a flexible double pendulum at various stiffness and hinge orientations. Aeroelastic simulations of a flexible wing with flared hinged wingtips are then conducted and compared against previous experimental and numerical results. Finally, a full-vehicle configuration featuring flared hinged wingtips is introduced based on a high-altitude, long-endurance T-tail aircraft. Aeroelastic trim and equilibrium states are computed for both the original vehicle and the modified aircraft with hinged wingtips for the analysis of 1⁢𝑔 plus gust responses in the vertical and lateral directions. Results shed light on the coupled nonlinear aeroelastics and flight dynamics exhibited by various configurations of varying mass and stiffness definitions in gust encounters. It is found that the response of the aircraft with flared hinged wingtips, considering geometrical nonlinearities, is predominantly bounded by that of cases with extended and upturned wingtips, with nonlinear trends in flare angle, gust lengths, and intensities uncovered and weighed in their contributions to the overall flexible aircraft dynamics.