Research on aircraft longitudinal flight control law identification based on QAR data

For a particular type of aircraft flight simulation, how to accurately describe the flight control characteristic is a problem. In this paper, research of aircraft longitudinal flight control law identification based on QAR (quick access recorder) data, first of all, the trim and linearization method of B737-800 six-dof nonlinear model is deduced, a linear state equation of a typical working point in cruise phase is given. Then, based on the linear model and on the basis of PID control structure, identify longitudinal flight control law in cruise phase, control law parameters are obtained. Finally gives a longitudinal flight control simulation example, the simulation results are compared with the actual flight data from QAR, the simulation results better describes the real aircraft flight control characteristics.