Abstract: Bow and side deck structures forming a part of the rigid body structure of an air cushion vehicle include a tubular circular section gunwale member and a tubular circular section chine member supported outwardly from a buoyancy tank structure which forms the base of the rigid body structure by frame members to which they are attached by welding. The bow and side deck structures are completed by hull plating attached to the gunwale, chine and frame members. The buoyancy tank structure may include unstiffened extruded deep I-section beams.

Abstract: A device for arresting the growth of a rip in reinforced flexible sheet material, for example elastomeric sheet material reinforced with woven nylon fabric, comprises a flexible sheath member having a flexible core member extending throughout its length and chemically bonded thereto. The sheath member includes tensile load path discontinuities at intervals along the length of the core member and at least in regions of the sheath member remote from the core member. The tensile load path discontinuities prevent tensile loads being transmitted along the length of those regions of the sheath member which are not bonded to the core member, such loads being diffused into the core member because of the bond between the sheath member and the core member. A number of these devices may be attached to an air cushion vehicle flexible skirt assembly manufactured from sheet rubber reinforced with woven nylon fabric so as to arrest the growth of rips which may propagate during operation of the vehicle.

Abstract: An attachment device for releasably connecting a flexible skirt component to rigid body structure of an air cushion vehicle has a plurality of first elements attached at spaced positions on the rigid body structure. A plurality of second elements are attached at spaced positions along an edge portion of the flexible skirt by a plurality of clamping plates which co-operate one with each second element to present a clamping face towards a clamping face on the second element. The edge portion of the flexible skirt is held between the clamping faces by a clamping action applied by releasable fasteners passing through aligned holes in the second elements, the clamping plates and the flexible skirt. The second elements are positioned in the spaces between the first elements so that respective longitudinal passages extending through the first and second elements are aligned, and a pin member is inserted into the aligned passages so as to connect the first and second elements in hinged relationship.