Abstract: A towed underwater vehicle that is laterally and vertically movable with respect to a towing vessel connected by a tow cable to the vehicle. Such movement of the vehicle is obtained by the interaction of a horizontally and vertically movable point of attachment of the tow cable to the vehicle, horizontal and vertical planing surfaces provided on the vehicle, and appropriate stabilization of the vehicle. Such stabilization is obtained by adding buoyant materials to upper portions of the vehicle, ballast to lower portions of the vehicle, use of adjustable ailerons or adjustable horizontal and vertical planing surfaces, or a combination of the preceding. When the point of attachment between the cable and the towed vehicle is changed, the forces exerted by the cable on the vehicle are changed so that the planing surfaces of the vehicle present an increased frontal area to water flowing past the vehicle. The increased frontal area struck by the water results in movement of the vehicle to minimize the frontal area.

Abstract: Apparatus for isolating from a body of water a predetermined bottom area and a volume of water or other liquid extending above the bottom area up to the surface of the body of water, comprising a flexible wall member with a flexible and conforming base section formed on its lowermost edge. The base section is adapted to be filled selectively from the surface of the body of water to anchor the wall member to the bottom. A float member is secured to the uppermost section of the wall member to keep the wall member floating above the surface of the body of water.