Aerodynamic parameter estimation for high-performance aircraft using extended Kalman filtering

The extended Kalman filter (EKF) was used to estimate the coefficients in models for the aerodynamic forces and moments for two high performance aircraft from flight data. The estimates of the lateral moment parameter for the X-31 drop model produced by the EKF are of quality similar to those obtained with linear regression methods in terms of the parameter estimate values and the indicated uncertainty, as given by the predicted error standard deviation. For the high-angle-of-attack research vehicle (HARV), the results for the longitudinal parameter show that a parameter pseudonoise assumption improve the effectiveness of the filter, provided that an appropriate value is chosen for the pseudonoise intensity matrix.