Abstract: An apparatus for defining the free surface of a moving column of a fluid in vertical pipe to enhance the accuracy of measurements of transient rate of flow of the fluid using electromagnetic flowmeter is described. It provides a neutrally buoyant plug which stays in contact with the free surface of the column of the fluid at all times and thus defines the free surface of the fluid moving in the vertical pipe accurately and reduces the oscillations of the free surface of the fluid.

Abstract: A submarine torpedo launching and control assembly has a multiplicity of pedo tubes each having muzzle and breech doors and a series of fluid operated mechanisms for operation of various elements and actuator valves for operating these mechanisms. A source of fluid under pressure and conduits therefrom to said actuator valves for operating said fluid operated mechanisms. A control panel has a series of manipulatable fluid control members associated with the actuator valves for operating the fluid operated mechanisms, and these members are movable from a first position to a second position to effect the direction of flow of fluid to and from the actuator valves and thereby to move the mechanisms between the first and second positions. Visual indicators indicate the position of the associated fluid control members and thereby that of the fluid operated mechanisms.

Abstract: A ring-loaded flexural disc spring acts as an isolation mount in a thin cndrical space in the tail of a longitudinal vibrator type of underwater sound transducer. The ring-loaded spring comprises a thin disc having a raised bearing surface at a specified distance from the perimeter on one side of the disc and a raised bearing surface at the perimeter on the other side of the disc. The spring flexes into a concave shape when a load is applied. The operation of the disc is linear over the entire specified load range.