Abstract: There is disclosed a marine vessel which is particularly suited for mine hunting operations or the like because of improved survivability characteristics in the presence of multi-directed underwater transmitted excessive shock or vibration forces, such as are generated by a nearby exploding mine or the like. The ship is of the propeller driven type having a propeller shaft driving engine and gearbox unit mounted inboard of the vessel hull upon a rigid sled-like platform which in turn is resiliently supported relative to rigid structure of the vessel by spring means sandwiched therebetween. The spring means are of such nature as to resiliently yield in response to excessive compression, tension, shear or roll forces encountered from any direction. The spring means comprises an array of spaced apart spring devices, and back-up blocks of non-resilient compression-deformable material are provided in association therewith.

Abstract: A novel exhaust system for both conducting engine exhaust gases away from and aft of the personnel occupied portion of a marine vessel and protecting the sides of the hull of the vessel from damages thereto during docking or other "working" maneuvers of the vessel is provided.

Abstract: There is disclosed an improved air cushion supported vehicle of the relatively high speed operating "surface effect ship" type, having a main hull and a pair of rigidly constructed opposite side walls or hulls depending therefrom, and bow and stern air cushion sealing means. Each of the side hulls terminates at its lower extremity into an outwardly side-wise canted water planing bottom surface or keel into which one or more non-coplanar surface discontinuities is/are provided for locally accommodating in slightly recessed relation therein the ship propulsion propellers. The configurations of said discontinuities are such as to reduce the requisite angles of the propeller driving shafts relative to the ship hull; thereby reducing the ship draft (propeller clearance) requirements, while also providing under high speed operating conditions improved propeller operating efficiencies and substantial maintenance of the desired air cushion sealing efficiencies of the side hull keels of the ship.

Abstract: There is disclosed in a surface effect ship which is constructed substantially of aluminum alloy material a hull construction including a side hull component which is bottomed by an operationally "wet" aluminum alloy keel plate, an improved propeller support arrangement comprising a superior strength thin-profile steel alloy strut extending cantilever-wise through the keel plate and carrying at its outer end bearing means for support of a ship propeller shaft. Interiorly of the side hull the steel strut is mechanically anchored to an operationally "dry" aluminum alloy member of the side hull structure, while at its underwater "wet" intersection with the aluminum alloy keel plate it is supported thereby but electrolytically and dynamically insulated therefrom by means of an epoxy-like housing device which at that cantilever support juncture encircles the strut.

Abstract: A rapidly reversible air propeller shroud system is provided for operating an air cushion vehicle more efficiently both in forward and reverse direction travel and maneuvering modes. The shroud includes a sectionally rigid portion of aerodynamically efficient form for operating the vehicle in one direction of travel; and in combination therewith an otherwise inoperative inflatable collar which may be rapidly inflated to expand so as to modify the aerodynamic characteristics of the shroud for operation of the propeller efficiently in reverse direction thrust mode.

Abstract: In a surface effect ship of the type having at least two relatively spaced wall-like stationary structures extending longitudinally beneath the main body of the ship into and below the water line of the ship to partially confine thereunder the ship support air cushion, and a seal device of the inflatable bag type extending laterally between the stationary structures to assist in sealing the air cushion beneath the ship; the seal bag being apertured through its opposite end wall portions to permit egress of air therethrough so as to lubricate movements of the end wall portions relative to the stationary structures.