Hierarchy-structured flight control combined with Dynamic Inversion, (HSDI) is considered as a promising approach for flight control law design not only to cope with nonlinear dynamics but to suppress increasing resources necessary for reliable flight control law development. The approach has already demonstrated its performance by simulation analysis in recently published papers. This paper discusses feasibility of the approach for the design of Silent Supersonic Technology Demonstrator (S cube TD or S3TD), which is a planned UAV by JAXA (Japan Aerospace Exploration Agency). First, it defines an operational flight envelope of S3TD and then designs the HSDI controller in the envelope. Second, it evaluates stability margins in overall range of the envelope. In order to satisfy the requirement of stability margin, the magnitude of gain should be scheduled with dynamic pressure and Mach number. Finally, the re-design scheduled-gain HSDI controller is evaluated by numerical simulations of various maneuvers. HSDI controller will be promising for S3TD by using a simple gain scheduling, where it preserves virtues of the approach.