Abstract: A hybrid craft can operate as a high speed SES in open water and deploy a retracted flexible skirt to operate as a hovercraft across beaches and overland. A downwardly extending boundary structure on a hull periphery reaches through the surface of water. The boundary structure has thin rigid side-walls extending downward from lateral sides, a forward seal wall extending downward from a forward portion, and an aft seal wall extending downward from an aft portion. Machinery creates a pressurized air cushion under the hull inside of the boundary structure to support and transport the hull. A flexible skirt system on said hull inwardly of and adjacent to the boundary structure can be retracted to a first position above the boundary structure and the water and extended to a second position below the boundary structure and the surface of the water to transit beaches and overland on the air cushion.

Abstract: A low profile deck clamp and cargo or deck equipment anchoring system which tilizes a removable, keyed deck clamp in association with equipment or cargo entity-provided attachment flanges, and also with preexisting deck sockets formerly used with other known prior art tie-down systems. The clamp in a more preferred form has a horizontal planar slotted body member disposed above deck, and a double offset unique key portion which downwardly depends from its forward end as a generally below-deck portion. Attachment flanges are initially or subsequently formed to the base of each cargo or equipment entity. An angular form of attachment flange with a planar base portion disposed parallel upon the deck, is provided with adjacently disposed key-passable clearance holes and a plurality of strategically placed threaded holes to manually and collectively cooperate with the deck sockets, the clamp's keyed portion and a plurality of anchoring bolts passing through the slots of the clamp's planar body member.