Lessons learned in the development of a multivariable control system [STOL and S/MTD programs]

A primary objective of the STOL (short takeoff and landing) and Maneuver Technology Demonstrator (S/MTD) program is the development of the Integrated Flight/Propulsion Control (IFPC) system. The use of modern multivariable control theory was required for this program, but in implementation a combined classical and multivariable design approach has been found to be the most efficient. The architecture defined by the multivariable approach was chosen for some control modes and that defined by the classical approach was chosen for others. The problems overcome in realizing an effective and practical implementation are discussed. Some recommendations for control-system research are presented