SEAKEEPING CHARACTERISTICS OF A HIGH LENGTH-TO-BEAM RATIO SURFACE EFFECT SHIP.

The results of experiments concerned with the vertical plane dynamics of a high length-to-beam ratio surface effect ship (XR-5) are presented. Spatial and temporal cushion pressure distributions are presented for regular and irregular waves. Experimental data are presented demonstrating the distortion of waves passing under the model. The experiments included pitch and heave oscillations to obtain stability derivatives. Captive model wave excitation forces and moments in head seas were determined by transient wave and regular wave techniques, with good agreement between these two techniques. Regular wave seakeeping transfer functions for head seas are well correlated with spectral analysis results from irregular seas. A vertical plane frequency domain simulation based upon captive model results shows good correlation with regular wave seakeeping transfer functions.