The Influence of Control Law on Yaw Maneuver Load about Civil Aircraft

Abstract

The fast and sharp deflection of rudder in aircraft maneuvering process can produce large aerodynamic loading on rudder and vertical fin, and transmit them to the rear fuselage, even cause the safety accident of reciprocated rudder pedalling of pilot. Based on yaw maneuver situation stipulated in article 25.351 of CCAR-25 and rudder control reversal situation stipulated in article 25.353 of CS-25, the CCAR25.331 and CS25.353 are firstly analyzed; then the maneuver simulation calculation for two yaw maneuver situations with/without the consideration of control law respectively is carried out; and finally a comparative analysis of the aircraft response and the vertical-tail load is conducted, and the influence of control law on yaw maneuvering load is analyzed. The results show that, for the yaw maneuver situation, the response amplitude of the aircraft is reduced after considering the control law, and the vertical-tail load is reduced; after considering the rudder control reversal, the response amplitude of the aircraft and the angle of side slip are increased, and the vertical-tail load is finally increased; the vertical-tail load caused by the rudder control reversal can effectively be reduced after considering the P-Beta control law.

Keywords

• yaw maneuver
• rudder control reversal
• control law
• vertical-tail load
• maneuver simulation