Theoretical development of an optimum air craft control system

Abstract

The material described in this report concerns the development of an improved control system for controlling the longitudinal motion of an aircraft in a low-altitude flight mode. To attain this goal two specific areas of investigation are pursued. Firstly, the development of an ideal aircraft flight path is considered. The formulation of this ideal flight path is made in such a manner that the flight path is conceptually meaningful from an' engineering point of view. In addition, the ideal flight path which is formulated is capable of being generated rapidly so that it becomes feasible to use this flight path in the real time control of low-flying aircraft. The second area of investigation concerns the development of an optimum controller for low-flying aircraft based upon in-flight computations of the ideal aircraft, flight path. The aircraft controller gains are obtained by minimizing a quadratic performance index. The index selected includes, in addition to initial and terminal error expressions, an integral of a quadratic error measure over an interval of time which is considerably shorter than the total operating time of the system.