In order not to overlook important loads or dynamic effects caused by drive train components when simulating wind turbines, a wind turbine environment is built up in the multibody simulation code SIMPACK. The simulation model consists of detailed aerodynamics, controllers and wind turbine components. The virtual gearbox includes gearbox shafts, bearings, and, at all stages, detailed gear wheels. These gearbox models are used within a complete virtual wind turbine for combined linear and non-linear analyses. The most important analysis methods are also described.