Estimation of Wind by Estimating Derivatives of Longitudinal Equations of Motion of Aircraft

Abstract

This paper considers the effect of wind on stability derivatives of longitudinal equations of motion of an aircraft and estimating steady wind by estimating the stability derivatives using an algorithm such as the least squares method (LSM). The wind defined in the inertial frame appears in the derivatives concerning the pitch angle in the linear form and is computed from the estimated derivatives. The numerical results computed for NASA's Generic Transport Model (GTM) verify the linear model in the presence of steady wind. The simulation results obtained for GTM using the LSM and an extended Kalman filter indicate that although the vertical wind has a significant estimation error, the horizontal wind is estimated well despite considerable estimation error of the stability derivatives. We also examined the reason analytically and numerically.