Linear Morison forces, which are applicable to small non-diffracting structures or parts of structures, are included in the Aqwa radiation/diffraction analysis and frequency domain statistic analysis. Therefore mixed models (diffracting and non-diffracting elements) may be analyzed. The contribution of the Morison elements on hydrostatic forces, hydrostatic stiffness matrices, and added mass and wave exciting forces, is calculated and written to the hydrodynamic database.

However, Morison drag forces, which are nonlinear, are not directly calculated in the radiation and diffraction analysis and the frequency domain statistic analysis. Linearization of drag forces can be optionally carried out if required.