The Euler equations of incompressible and inviscid fluid are used for control equations of the stern flow field, and the propeller is computed by lift line theory.

Both lift line model and generalized wake model are founded in this paper. A method is given for calculating induced velocities by a wake vortex line which results in a rapid convergence.

I snapped this coming down from our first run, the sharp line at the top of the cloud bank made it seem like a sea that was slowly encroaching on the hut at the base of the lift.