WAVE-INDUCED MOTIONS OF A LARGE ROCKET VEHICLE DRIFTING IN A VERTICAL ATTITUDE

Abstract : Results are presented of a theoretical and experimental laboratory study of the movements of a large solid-propellant rocket vehicle drifting in a vertical attitude in uniform waves and in the wave environment of the open sea. Measurements were made of the movement in heave and pitch of a 1-120 scale model of a 175-ft long vehicle. Experimentally obtained results compared well with those obtained analytically. It appears that heave and pitch are linear functions of the wave height and nonlinear functions of the wave frequency. Pitch and surge are coupled. On basis of the linear response of the vehicle to uniform waves, statistical features of the response in heave and pitch to ocean waves with a particular spectrum are calculated.