In this paper, a disturbance observer-based command filtered backstepping control scheme is proposed to handle parametric uncertainties of hypersonic flight vehicles. The dynamics of an electromechanical actuator with parametric uncertainties are investigated effectively. Then, the lumped disturbances caused by parametric uncertainties and external disturbance torque are estimated by fixed-time observers. Fixed-time filters and compensation signals are constructed to handle the explosion of terms problem and ensure that the filter errors converge to zeros. The tracking error converges to zero in fixed time. Finally, the effectiveness of the proposed control scheme is illustrated through simulation results.