Full Conventional Envelope Longitudinal Axis Flight Control with Thrust Vectoring

A full conventional envelope longitudinal axis control design is presented for a thrust-vectoring fighter aircraft. An inner-outer loop modular control structure is used to provide good flying qualities in the presence of highly structured uncertainty across a wide flight envelope. Simple, low-order control laws are designed for a version of an F-18 aircraft model. A minimal-order H∞ design algorithm is used to aid in the design of an inner loop equalization controller. Structured singular value synthesis is used to design outer loop implicit model-following controllers. Structured singular values are used to analyze stability robustness to structured parametric uncertainty and actuator and sensor unmodeled dynamics. Nonlinear simulation is used for aircraft control system performance evaluation for large amplitude commands.