Transonic rudder buzz responses based on the computational fluid dynamics or computational structural dynamics(CFD/CSD)loosely method are analyzed for a tailless flying wing unmanned aerial vehicle(UAV).The Reynolds-averaged Navier-Stokes(RANS)equations and finite element methods based on the detailed aerodynamic and structural model are established,in which the aerodynamic dynamic meshes adopt the unstructured dynamic meshes based on the combination of spring-based smoothing and local remeshing methods,and the lower-upper symmetric-Gauss-Seidel(LU-SGS)iteration and Harten-Lax-van Leer-Einfeldt-Wada(HLLEW)space discrete methods based on the shear stress transport(SST)turbulence model are used to calculate the aerodynamic force.The constraints of the rudder motions are fixed at the end of structural model of the flying wing UAV,and the structural geometric nonlinearities are also considered in the flying wing UAV with a high aspect ratio.The interfaces between structural and aerodynamic models are built with an exact match surface where load transferring is performed based on 3Dinterpolation.The flying wing UAV transonic buzz responses based on the aerodynamic structural coupling method are studied,and the rudder buzz responses and aileron,elevator and flap vibration responses caused by rudder motion are also investigated.The effects of attack,height,rotating angular frequency and Mach number under transonic conditions on the flying wing UAV rudder buzz responses are discussed.The results can be regarded as a reference for the flying wing UAV engineering vibration analysis. Transonic rudder buzz responses based on the computational fluid dynamics or computational structural dynamics (CFD / CSD) loosely method are analyzed for a tailless flying wing unmanned aerial vehicle (UAV). The Reynolds-averaged Navier-Stokes (RANS) equations and finite element methods based on the detailed aerodynamic and structural models are established, in which the aerodynamic dynamic meshes adopt the unstructured dynamic meshes based on the combination of spring-based smoothing and local remeshing methods, and the lower-upper symmetric-Gauss-Seidel (LU-SGS ) iteration and Harten-Lax-van Leer-Einfeldt-Wada (HLLEW) space discrete methods based on the shear stress transport (SST) turbulence model are used to calculate the aerodynamic force. The constraints of the rudder motions are fixed at the end of structural model of the flying wing UAV, and the structural geometric nonlinearities are also considered in the flying wing UAV with a high aspect ratio. The interfaces between structural and aerodynamic models are built with an exact match surface where load is carried based on the aerodynamic structural coupling method are studied, and the rudder buzz responses and aileron, elevator and flap vibration responses caused by rudder motion are also investigated.The effects of attack, height, rotating angular frequency and Mach number under transonic conditions on the flying wing UAV rudder buzz responses are discussed. The results can be viewed as a reference for the flying wing UAV engineering vibration analysis.