A SIMULATION MODEL OF SHIP GROUND EFFECT FOR ROTORCRAFT / SHIP INTERACTION STUDY

A simple ground effect model for rotorcraft / ship dynamic interactions, which is suitable for implementation in flight simulators for real-time simulation purposes, has been extracted from the analysis of the aerodynamic interaction results obtained from a computationally intensive method that incorporates a rigid rotor wake and a panel representation of the ship with corresponding image systems. It is found that the ground effect is very sensitive to the helicopter position with respect to the ship deck, as well as the height above the deck. The inflow gain matrix in dynamic inflow model is modified as a function of the position relative to the deck. Numerical results for a SH-60 helicopter flying above the deck of a moving FFG-7 class frigate at the same speed as the ship are presented and discussed in this paper. Results show that the extracted model is able to capture the ship ground effect well at various locations over the ship deck