Abstract: A method of transient aeroelastic rotor response analysis was developed and used to investigate shipboard engage/disengage sequences of the helicopter rotor.The blade was modeled as an elastic beam undergoing flap,lag torsion and axis deflections.The weight of blade and the inertia force due to the variation of rotation speed were taken into account.Blade element theory was used to calculate unsteady aerodynamic loads in linear and nonlinear regimes.The experimental data validated this analysis.The parameter effects on transient response were investigated.