The ability of Maritime Unmanned Systems (MUS) to perform certain tasks is often closely linked to their endurance. This article presents experimental results on a vehicle equipped with a wing system, designed to exploit wave motion for propulsive thrust. After a brief overview of the current state of the art and its limitations, the operating principle of the system is described. Results from sea trials with an initial prototype airfoil are then presented, demonstrating the possibility to generate a zero-cost propulsion. Additionally, a
second set of controlled environment tests is reported, where waves of varying height, period, and shape were generated to evaluate the system's performance under different conditions. The findings suggest that this innovative approach can significantly reduce the energy used for propulsion, thereby enhancing the endurance of MUS.

Keywords: AUV; MUS; Wave propulsion; energy harvesting; sea trials