Aircraft Trajectory Simulation and Stability Analysis Considering Cross-Derivatives and Cross-Coupling Derivatives

This study develops an aerodynamic model incorporating cross-derivatives and cross-coupling derivatives to analyze their effects on the dynamic characteristics of a quasi-HyTRV hypersonic lifting-body UAV. The research indicates that cross-coupling derivatives exert minimal influence, while cross-derivatives significantly diminish lateral-directional stability. This reduction can induce severe attitude-angle variations or even divergence during the terminal flight phase, resulting in a turning trajectory with a continuously decreasing radius. This study reveals the substantial engineering impact of cross-derivatives on hypersonic lifting-body UAVs, providing critical guidance for aerodynamic modeling and flight-dynamic analysis.