Horizontal axis wind turbines are subjected to various static and dynamic loads under different load situations. Aeroelastic modelling is used in wind turbines to couple the aerodynamic and structural loads acting on the turbine and to analyse the aeroelastic response. The small wind turbine Nimbus 1.6 KW has been modeled in the Aeroelastic code HAWC2 which uses Multibody dynamics for the structural modelling and BEM theory for the aerodynamic part. The natural frequency and different modes of the turbine has been calculated after the complete modelling in HAWC2