Abstract : This report describes an aeroelastic analysis that provides a complete description of the dynamics and aerodynamics of fully coupled helicopter main or tail rotor/airframe/control systems. The analysis is designed to study stability characteristics in conditions of pure axial flow or in forward flight, for which it computes the systems eigenvalues and eigenvectors. For hover studies, the aerodynamic derivatives include stall and compressibility effects, and circulatory and noncirculatory unsteady effects are accounted for through use of Theodorsen and Loewy type lift deficiency functions. The forward- flight aerodynamic derivatives are obtained from any appropriate linear or nonlinear time history analysis. The approximations made in the forward-flight analysis limit such applications to an advance ratio of about 0.5.