STUDIES ON THE TIME-TO-GO INDEXING CONTROL SCHEME FOR AN AUTOMATIC AIRCRAFT LANDING SYSTEM.

The synthesis procedure of the automatic landing system of an aircraft is presented in this study in three phases. The problem is first formulated in the nominal time domain as a linear tracking problem specifying the desired trajectories and related performance requirements, and the time variable feedback gains and input signals are obtained by applying the deterministic optimal control theory. These feedback gains and input signals are indexed by time-to-go or equivalently by distance-to-go so as to control the touchdown point with appropriate accommodation for the distortion between the nominal time frame and the time-to-go time frame. The effects of the extraneous disturbance input due to wind velocity are considered deterministically and suitable compensation signals are included.