Abstract: A free fall escape vehicle has surfaces of a deceleration structure that decelerate the vehicle upon entry into the water at a rate no greater than 4 g to 10 g by progressively increasing in area towards an escape vessel of the vehicle. In one form, the deceleration structure is circularly symmetrical normal to its axis, which can be approximated by a series of spaced-apart shells, each shell being a zone of a sphere the center of curvature of which is at or above the center of gravity of the escape vehicle; the condition can also be approximated by truncated sections of right circular cones. An escape vehicle similar to a lifeboat has a wedge-shaped deceleration structure with the sides of the wedge paralleling the fore-and-aft axis of the vessel, the structure can be approximated by a series of right circularly cylindrical shells or flat plates both having an effective center of curvature at or above the center of gravity of the vehicle.

Abstract: Apparatus for substantially reducing the roll and pitch motions of a floating vessel in commonly occurring seas is described. The apparatus comprises a recessed cavity formed in a substantial area on the bottom of the hull of the vessel and has an airblower coupled to the cavity for introducing air into it. The apparatus may include horizontal planes for restoring the effect of the added mass of the water on the stability of the vessel.

Abstract: A seagoing vessel is stabilized by a passive system including tanks symmetrically disposed on the vessel below the water line. The tanks are connected by a conduit and pressurized with air to a selected pressure level. During each oscillatory roll and/or pitch cycle of the vessel, the tanks alternately fill and drain with selected volumes of water, thereby to reduce the righting moment of the vessel. The period of oscillation of the vessel is lengthened beyond the period of wave motion.