Full scale measurement of underwater radiated noise from a coastal tanker

Measurement of underwater radiated noise (URN) from ships is challenging due to the adverse and changeable underwater environment, the difficulty of obtaining measurement slots with merchant vessels, and the required synchronization of measurement data from sensors of different modalities in different locations. SSPA have participated in the development of a proposed measurement standard for URN measurement in shallow waters within the EU-funded AQUO project. SSPA have also performed measurements of the underwater radiated noise from the coastal tanker M/T Olympus as part of the AQUO project. These measurements were aimed at characterizing the URN of M/T Olympus as well as evaluating the proposed measurement standard. In this paper we report on our measurement campaign, the equipment used, the procedures undertaken, the methods of data analysis, and the resulting underwater radiated noise spectra. URN spectra are compared to pressure pulse measurements from the vessel´s hull as well as cavitation videos from an underwater camera. Finally we use the AQUO measurement procedure with AIS data to estimate URN from a vessel to which we do not have access.