Recent advances in composite structures and active control systems havemade the concept of a forward swept wing aircraft a viable alternative to themore conventional configurations.This thesis encompasses some of the work resulting from a three yearresearch program covering the dynamic behaviour and characteristics of aFSW aircraft having a closely coupled canard. The dynamic model has beenbased on the output of a first order optimisation routine with emphasis onminimum induced drag and static margin as the two most important criteria.Stability characteristics of the dynamic model were extracted from thetransient response tests in both longitudinal and lateral modes by means ofa statistical method, namely Extended Kalman Filter (E. K. F. ). In carryingout the dynamic tests, use was made of the facilies outlined by Ref. 8.Validated through computer based experiments, the Extended KalmanFilter algorithm has successfully been applied to the open-loop wind tunneltests. Simulations of the equations of motion using estimates of stabilityderivatives obtained in this way closely match the observed behaviour.Furthermore, substitution of aerodynamic data obtained via static windtunnel measurements in theoretically derived expressions for some of thestability derivatives has resulted in an alternative set of stabilityderivative estimates. 'Finally, estimates of the stability derivatives obtained with the E. K. F.,first order optimisation program and static tests are compared. Althoughthe results are limited to very low subsonic Mach numbers, nevertheless, theyare very encouraging. It is hoped that future work might extend the studiesinto unstable flight regimes.
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