EU unveils $5.6-million plan to build quieter underwater drones

The European Defense Agency (EDA) has launched a €4.8-million ($5.6-million) research initiative called SPHYDA (Submarine Hull/Rudder/Propeller Hydrodynamics Interaction and Hydroacoustics) aimed at reducing the acoustic noise generated by autonomous underwater vehicles (AUVs). Over four years, the project seeks to analyze how noise arises from the interaction of hull shapes, rudders, and propellers, with a particular focus on hydrodynamic noise caused by propulsion systems that generate cavitation. By developing advanced numerical models and experimental methods, SPHYDA aims to create digital design guidelines for quieter, stealthier underwater drones, which will provide strategic military advantages and help protect marine life. The project involves nine industrial and research partners from Italy (the lead nation), Germany, the Netherlands, Spain, and Norway. After building and validating digital models, SPHYDA will proceed to tank testing and real-world sea trials to measure far-field noise. The initiative reflects a broader