An investigation of the hydrodynamic stability and spray characteristics of high length/beam ratio seaplane hulls with high beam loadings

Abstract

Tests have been made on a series of high length/beam ratio seaplane hulls with high beam loadings. The effects of varying the hull parameters, forebody warp, afterbody length and afterbody angle, together with the interaction of these effects, and of tailoring the afterbody, on the calm water hydrodynamic stability and spray characteristics of the series have been determined. To amplify this work, investigations have been made into the effects of load, moment of inertia and radius of gyration, and slipstream, together with a limited assessment of longitudinal hydrodynamic stability characteristics in waves. Dynamic models were used and tests for the main investigation consisted of assessments of longitudinal hydrodynamic stability characteristics, both undisturbed and disturbed, at two weights, of spray behaviour at these weights, and of directional hydrodynamic stability characteristics at the higher weight only. Improvements in test techniques are described and, where appropriate, reference is made to earlier work on hulls of low length/beam ratio.