A flying wing configuration with highly swept leading edges and low aspect ratio such as the generic UCAV configuration DLR-F19 is very attractive for military applications due to its very favorable stealth capabilities as well as its high agility. To assure good flying qualities, however, is a critical aspect for such a configuration. It should thus be considered early in the design process. This paper presents an innovative way to derive a flight dynamics model from wind tunnel experiments by applying a system identification approach, normally employed for flight tests. This allows the modelling of nonlinear aerodynamic effects and provides a model which can be integrated directly into flight dynamics simulations. New wind tunnel maneuvers are applied, which significantly reduce the time of the wind tunnel experiments and improve the quality of the aerodynamic dataset generation. The aerodynamic model is then integrated into a 6-degreesof-freedom simulation environment in order to perform a flight dynamics analysis of the UCAV configuration. The purpose of this analysis is to compare the flying qualities as derived from wind tunnel data with the numerical results determined on the basis of potential flow methods used in preliminary aircraft design. Keywords system identification, parameter estimation, flying qualities analysis, wind tunnel experiment, aerodynamic modelling, UCAV LIST OF SYMBOLS α angle of attack, [°] α* angle of attack where half of airflow is detached, [°] β angle of sideslip, [°] Δα angle of attack difference between current and next breakpoint, [°] ΔC i j delta coefficient of the force or moment i, whose strongest influence is parameter j, [-] Δti equivalent time delay of parameter i, [s] Φ bank angle, [°] Φt critical bank angle for roll performance, [°] ω0 natural frequency, [rad/s] a1 reduction in slope of the lift curve, [-] Bp breakpoint, [-] Ci coefficient of force or moment i, [-] Ci0 basic coefficient of force or moment i, [-] Cij non-dimensional derivative of force or moment i with respect to j, [-] Cijα angle-of-attack-dependent non-dimensional derivative of force or moment i with respect to parameter j, [-] CDX, CmX hysteresis influence factor on drag and pitching moment, [-] D damping ratio, [-] FvD vortex drag factor, [-] f0 model oscillation frequency, [Hz] fs sampling frequency, [Hz] g gravity constant, [m/s²] Ixx,Iyy,Izz moment of inertia in x/y/z-axis, [kg m²] L, D, Y aerodynamic lift, drag and side force [N] L β , N β dimensional roll moment derivative with respect to sideslip angle, [1/s²] LIB left inboard control surface, [°] LOB left outboard control surface, [°] l, m, n aerodynamic moments, [N m] N r dimensional yaw moment derivative with respect to roll rate, [1/s] nz vertical load factor, [-] p, q, r roll rate, pitch rate, yaw rate, [rad/s] V velocity [m/s] RIB right inboard control surface, [°] ROB right outboard control surface, [°] SP20 split flap with 20 % chord depth, [°] SP25 split flap with 25 % chord depth, [°] T2 time to double amplitude, [s] t time, [s] X non...
