Fuel saving is the major reason for making underwater hull cleaning an integral part of planned maintenance. A buildup of marine fouling can lead to increased drag, resulting in a detrimental impact on a vessel’s hydrodynamic performance and hence the relationship between speed, power performance and fuel consumption. Fouling, particularly in the case of a prolific buildup of ‘hard or shell fouling’ like barnacles or tubeworm, can cause turbulence, cavitation and noise frequently affecting the performance of soners, speed logs and other hull mounted sensors.