The new Fisheries Research Vessel “Oscar Dyson”, recently delivered to National Oceanic and Atmospheric Administration (NOAA), was designed and built by VT Halter Marine, Moss Point (USA). The vessel has been outfitted with state-of-the art sonar technology, but it’s most significant feature is that it has been designed to be “acoustically” quiet underwater. The underwater radiated noise requirements were those specified by the International Cooperative for the Exploration of the Seas (ICES) and the specialist company Noise Control Engineering (NCE), of Billerica Massachusetts, undertook engineering responsibility to meet those requirements.

NCE is an engineering consulting firm which specializes in shipboard noise and vibration control, and marine acoustics. The company engineers performed all noise prediction calculations, recommended the treatments necessary to meet the stringent underwater noise requirements and conducted an extensive sound and vibration testing program. NCE used Designer Noise, a new 3-D acoustic modeling program developed by the company in cooperation with Proteus Engineering (USA). Noise reduction solutions were optimized in the context of the overall vessel design, which resulted in additional benefit - weight reduction.

All efforts were concluded during seven sea trials undertaken to conduct extensive measurements of compartment noise, equipment vibration, ship-wide vibration and sonar self-noise surveys. As part of the final proof of performance, NCE also conducted a comprehensive underwater radiated noise survey.