Dynamic wave loads on a high speed catamaran ferry fitted with T-foils and stern tabs

Measurements of unsteady stress have been made on an INCAT wave-piercing catamaran during an extended period of passenger operations under varying sea conditions, vessel speed and heading relative to the sea. It has been found that the stress fluctuations are consistent with unsteady bending of the hull cross section. The measured results are compared with the predictions of a time domain, spatially fixed, strip theory method suitable for computation at high Froude number. It is found that there is a progressive nonlinear reduction of global bending moment and sectional shear fluctuations relative to wave height as the wave height increases. The intensity of the observed stress fluctuations is shown to be consistent with the loading predictions of the time domain method. © 2005: Royal Institution of Naval Architects.