Assessment of Mechanical Properties of Helicopter Cyclic Pitch Control Stick

The mechanical characteristics of a helicopter cyclic pitch control stick play a critical role in flight control performance and handling-quality evaluation. Existing assessment approaches mainly rely on force-gradient measurements and lack comprehensive characterization of control response behavior. This study proposes an integrated evaluation framework combining quantitative measurement and qualitative flight assessment for cyclic pitch control systems. Quantitative evaluation includes control-force and control-displacement characterization based on control-envelope modeling, highresolution force– displacement data acquisition, and dynamic response analysis. Qualitative evaluation incorporates pilot assessments of stick centering, jump behavior, and dynamic control characteristics under representative flight conditions. Experimental investigations conducted on a civilian light helicopter demonstrate that the measured controlforce gradients, operating strokes, trim-control displacement bands, and damping characteristics satisfy handlingquality requirements. The results further show that longitudinal and lateral control responses exhibit distinct forcedisplacement characteristics that support ergonomic operation and stable flight control. By establishing the relationship between control inputs, dynamic response behavior, and pilot perception, the proposed framework provides a systematic methodology for flight-control evaluation. The study offers an engineering-oriented approach for assessing human–machine interaction, control-signal responsiveness, and dynamic performance in helicopter flightcontrol systems.