The aim of this thesis is to evaluate an alternative design for the lateral-directional primary control laws for the M346 "Master" Advanced Trainer Aircraft, using modern design techniques. The proposed design has been developed for a limited but significant flight envelope (in term of AoA and speed range): the resulting closed loop system tracks roll rate and angle of sideslip (AoS) as commanded by the pilot by means of lateral stick and pedal deflections, with the required handling performance, for each mass and aerodynamic tolerance case. The selected approach is based on the Linear Quadratic theory. The application of the LQR technique allowed all the control gains to be computed simultaneously, and provided guarantee of large stability margins.

The first part of the thesis presents the design techniques used in this work.

The second part describes the linear stability and handling criteria that will be used to analyze effects and characteristics of the proposed control laws.

The third part presents the control laws Synthesis.

In the fourth part the reader will find the design validation for the controller.

The fifth part is dedicated to the results presentation.