DIRECTIONAL WAVE SPECTRA FROM A SWATH SHIP AT SEA

During the Surface Wave Dynamics Experiment (SWADE), the swath ship Fr ederick, G. Creed was equipped with an array of wave staffs for the es timation of wave directional spectra. This paper reports on the first such estimates taken from a ship at sea. An algorithm for removing the effects of the ship motion, including those resulting from the Dopple r shifting of observed frequencies, is presented along with some resul ts from the SWADE experiment. A comparison with directional wave spect ra taken from a nearby buoy shows the fidelity of the method.