Limited simulator aircraft handling qualities evaluation of an adaptive controller

The paper details the application and handling qualities evaluation through computer-based simulation of an adaptive model reference controller acting on the longitudinal modes of a fighter-type aircraft. Whereas classical control designs depend largely on a priori knowledge of the system dynamics, adaptive control algorithms do not require the same degree of a priori sophistication, or alternately the same controller can be applied on a plant with varying dynamics such as experienced by an aircraft over a wide range of flight conditions. Although the applications of an adaptive controller are well understood, much of the existing research focuses on an adaptive controllers' ability to track a basic input (such as step, ramp, or sinusoid) over a range of time-varying plants. In this research the adaptive controller is evaluated through a series of pilot-in-the-loop tracking tasks utilizing the boundary avoidance tracking technique designed to highlight potential control difficulties which may lead to pilot-in-the-loop oscillations, task abandonment or loss of control. The results presented will serve as a precursor to flight tests of adaptive controllers on-board next generation fighter aircraft.