Research On Iced Aircraft Flight Dynamics Characteristics And Envelope Protection Control Law

Aircraft flight dynamic and envelope protection control law in Smart Icing System are researched in this thesis. Firstly, the study about flight icing is reviewed at the beginning. The condition of icing accretion, the style of icing accretion, the parameters of icing accretion in flight, and the influence of icing accretion on the aerodynamic characteristics of an airplane are analyzed. Secondly, the development of aircraft icing avoidance technique, namely, the design idea, composing and function of Smart Icing System are introduced. On the basis of these, a simplified iced aerodynamics model is established, describes the effects of aircraft icing on aerodynamic parameters. Main principle and implement method of Iced Aircraft Envelope Protection system are proposed. After ascertain iced aircraft envelope, for pilot and autopilot, open-loop and close-loop aircraft envelope protection control law respective designed, ensure the aircraft will efficiently follow the flight path specified by the pilot in the safe-flight envelope. Finally, iced aircraft simulation model is established, and aircraft envelope protection simulations are implemented. For realize iced aircraft envelope protection, the means of iced aircraft aerodynamic parameter identification is also preliminarily discussed in the thesis.Simulation results demonstrate that Iced Aircraft Envelope Protection is capable of successfully avoiding incidents and accidents during flight in icing conditions, provide flying safety, operate definite action on the design of next generation civil airplane.