Development of an air-to-air refueling automatic flight control system using Quantitative Feedback Theory

Abstract

Abstract : Quantitative Feedback Theory and the improved method Quantitative Feedback Theory are enhanced to include the rejection of disturbance at the system output. The enhanced Quantitative Feedback Theory and improved method Quantitative Feedback Theory processes are applied to the design of an automatic flight control system to regulate position of the C-135B fuel receiving aircraft relative to the tanker during air-to-air refueling. A simple feedback control system is developed that will achieve stable position regulation. State-space aircraft models &re generated. An inner loop autopilot is designed to reduce the plant cutoff frequency and provide the system inputs for the Quantitative Feedback Theory compensators. Disturbance models representing disturbance due to wind gusts and refueling are developed. The flight control system is designed using the enhanced Quantitative Feedback Theory equations. Linear simulations &re performed on MATRIX, and nonlinear simulations are run on EASY5x. The results of the simulations show excellent results. The simulation results indicate that air-to-air automatic flight control system are technically achievable, and that implementation in USAF aircraft is possible.... QFT, Flight control, Air-to-air refueling, Disturbance rejection, Regulation control.