Abstract: A helicopter skid having a wall defining an elongated generally cylindrical tubular cross section, and a web extending vertically along the longitudinal axis of the skid between a bottom portion and a top portion of the wall. The top and the bottom portions of the wall have a tapering thickness with maxima where the web meets the top and bottom portions. The web is preferably formed integrally with the wall. A horizontal member formed integrally with the side portions of the wall of the tube extends horizontally through an aperture in the web.

Abstract: An air support unit for use in a modular air support bed has a common base pad of pliable material and inflatable elements releaseably fastened to one side of the base pad to define a body support surface. The air support unit constitutes a lightweight, foldable module easily and quickly interchangeable in a given bed with other modules having different patient support characteristics. The air support unit may be contained in a coverlet having a detachable top for easy access to the air support unit. An interior frame of resilient foam may be provided around the air support unit inside the coverlet for enhanced edge support.

Abstract: A bicycle utility carrying rack has a two piece clamp and a separate carrying grid. One clamp piece is bent to form a square-ended head which fits in a channel in the grid. The grid can be assembled to the clamp in one of two mutually perpendicular orientations for flexibility in mounting at various points of a bicycle frame. A single bolt secures the grid to the clamp and once assembled, the grid cannot turn about the bolt to another position unless disassembled from the clamp.

Abstract: In a stirling cycle machine a shell means enclosing the machine body for maintaining a substantially sealed atmosphere about the machine body. A diffuser arranged between the machine body and the outer shell for diffusing a shock wave traveling towards the outer shell as the result of an explosive failure of the machine body.