Robust Integrated Flight and Propulsion Controller for the Harrier Aircraft

An integrated longitudinal plus lateral e ight and propulsion control system is designed for the Harrier short takeoff and vertical landing aircraft, using the technique of H1 loop shaping. This centralized controller is parti- tioned via a step by step procedure, which generates both nominal performance and robust stability specie cations for the engine subsystem. Performance properties of both the centralized and partitioned systems are validated via nonlinear simulation. Implications of the design experience for the implementation of a full integrated e ight and propulsion control system on the Harrier are considered. trainer, which has been e tted with an experimental digital e ight control system, designed to permit e ight testing of experimental e ight control laws. VAAC is a U.K. Ministry of Defence program with the objectives of e ight demonstration of advanced vertical or short takeoff and landing (V/STOL) e ight controls and handling qualities assessment techniques. Under this program several exper- imental control laws for the Harrier have been developed for the DERA, 1 and these designs have been evaluated both on the full motion piloted simulation facilities at DERA Bedford and in e ight tests. Also, in Refs. 2 and 3, successful e ight tests are reported for experimental control laws for the Harrier, designed using modern multivariable techniques. These control laws have, however, not at- tempted to fully integrate the e ight and propulsion control systems and have, in general, been restricted to controlling the longitudinal motion of the aircraft. The aim of the e rst phase of the project carried out at Leicester University for the DERA was to develop a systematic methodology forintegratede ightandpropulsioncontrol (IFPC)systemdesignfor the Harrier,using multivariable robust controller design techniques. Preliminary results from the project have been presented in Refs. 4 and 5. In this paper details are given of the application in nonlinear simulationofthedevelopedIFPCmethodologytotheVAACHarrier aircraft in the 80-kn transition e ight phase.