A marine hydrokinetic (MHK) cycloturbine is a renewable electric power generation system used in rivers or tidal environments to address the need for electricity in remote regions. MHK cycloturbines have hydrofoils oriented perpendicular to the flow in a paddlewheel configuration, and use lift generated from these foils to produce power. Due to the high cost associated with its operation and maintenance, an MHK system with four stacked counter-rotating turbines that can self-deploy and with propulsion and control mechanisms similar to a cycloturbine aircraft has been designed. A detailed turbine simulation model is necessary to understand the vehicle dynamics and assist in the design of the vehicle controllers. The simulation model solves the six degree-of-freedom rigid body equations of motion for the maneuvering MHK system subject to the hydrodynamic lift and drag forces, hydrostatic forces, and the propulsive forces from the turbines. The turbine propulsive force model is matched to computational fluid dynamics analysis and experimental data. Experimental work includes investigation at 1/5.56 scale of a single turbine rapid prototype device and a subscale demonstrator in a reverberant tank.