A nonlinear signal processing framework for rapid identification and diagnosis of structural freeplay

•A robust nonlinear signal processing framework for rapid freeplay diagnosis is presented.•Nonlinear system identification methods are used to derive temporal and spectral diagnostic signatures.•Functionality demonstrated via flight test case study with stabilator freeplay.•The dataset considers significant deviation in Mach number and high AoA maneuvers giving rise to aerodynamic nonlinearity and uncertainty.•Freeplay is identified in the HTail actuator and the magnitude is tracked over three years and several maintenance cycles.