An experimental investigation of rigid flat-bottom body slamming was performed at the David Taylor Model Basin by dropping a 20-in. X 26.5-in. X 0.5-in. steel plate from various elevated positions above a calm water surface. Because of the effect of the trapped air between the falling body and the water, the maximum impact pressure measured was much lower than the pressure expected, if the generally accepted acoustic pressure formula ρcV0 is applied.

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A series of experimental investigations of rigid-body slamming was performed at the Naval Ship Research and Development Center by dropping one flat-bottom steel model and five wedge-shaped steel models with small deadrise angles (up to 15 deg) from various elevated positions above a calm water surface. The test results were used to provide a set of charts for estimating the maximum impact pressure due to rigid-body slamming of wedges.

An analytical method is proposed for determining wave impact "slamming" pressures on all types of ship hulls including advanced vehicles that may travel at speeds up to 100 knots and even higher speeds. The method is based on the Wagner wedge impact theory, the Chuang cone impact theory, and experiments performed at the David W. Taylor Naval Ship Research and Development Center. Determination of the impact pressure is based on the hypothesis that the impact velocity is equal to the relative velocity normal to the impact surface of the moving body and the wave surface. The proposed method has been verified by several model tests in waves and by actual ship trials of the catamaran USNS Hayes. Computer programs are included for the practical use of the method.