MOTIONS OF A DEPTH CONTROLLABLE TOWED VEHICLE.

Several calculation techniques are developed for estimating the performance of the towed vehicle. The submerged depth of the vehicle is a function of the angle of the main wings and advance speed of the towing vessel when the towing point, dimensions of the vehicle and towing cable are given. The relations between the submerged depth, wing angle and advance speed are obtained from static calculations. The drag coefficient and lift coefficient of the vehicle are obtained from model experiments. Transient motions of the vehicle and cable are induced by changing the submerged depth, advance speed and course. Motions induced by incident waves on the towing vessel cause corresponding motions of the towed vehicle. A three-dimensional numerical simulation technique is developed in this study for estimating these motions of the towed vehicle and cable.