Full envelope flight control system design using QFT

A controlled plant´s characteristics can vary widely throughout its operational envelope. This is a major problem in nominal plant based control system design. Hence, gain scheduling is often used for full envelope design. In this paper, it is proposed to address the plant´s variability using robust control design concepts. In particular, the frequency domain based quantitative feedback theory multiple-input multiple-output robust control design method is employed for the synthesis of a full envelope flight control system for an F-16 derivative. Compensators and prefilters for the aircraft´s pitch and lateral/directional channels are designed to meet Level 1 flying qualities, and these designs are validated through simulations.