- In the present study, a numerical time-domain model has been developed for the fully coupled dynamic analysis of an offshore floating wind turbine system including blade-rotor dynamics, mooring dynamics, and platform motions. The performance of the National Renewable Energy Laboratory (NREL) mini-TLP-type system in a typical wind-wave condition has been simulated and analyzed. In the present case, the dynamic coupling between the rotating blades and the floater is also considered in addition to the mooring-floater dynamic coupling. It is seen that the rotor-floater coupling effects increase with blade size. The increased coupling effects tend to increase the dynamic tension on tethers especially in the high-frequency region. The significantly increased dynamic tension not only increases the maximum tension but also reduces its fatigue life by increasing both stress level and number of cycles. The developed technology and numerical tool are readily applicable to the design of new offshore floating wind farms planned in the future. Copyright 2008 by The International Society of Offshore and Polar Engineers (ISOPE).