Abstract: A method of reinforcing a sandwich panel having opposed first and second skins spaced apart by a core having a thickness "F" in a manner to preserve the spacing between the skins, including the steps of boring an in-line hole through the panel to provide a hole in both skins and the core of a diameter "A", enlarging the hole in the first skin to a diameter "B", inserting a tubular sleeve into the in-line hole, the sleeve having a length substantially equal to "F" and having an external diameter greater than "A" and slightly less than "B", the first end of the sleeve contacting the inner surface of the second skin, and flaring the second end of the sleeve to an external diameter greater than "B" so that it engages the inner surface of the first skin, and inserting a bolt through the sleeve, the bolt having a head to contact the external surface of the first skin and applying a nut to the bolt to contact the external surface of the second skin so that the skins are held in fixed position by the bolt.

Abstract: A multi-layered, unbalanced, bonded sandwich panel having improved top load support capability per unit of weight is disclosed. The panel has a core, to the upper surface of which is affixed a multiple-ply top laminate. Similarly affixed to the lower surface of the core is a multiple-ply bottom laminate. The top laminate is thicker than the bottom laminate and supplies increased compressive resistance, while the bottom layer has an enhanced ability to withstand tensile forces. The core is preferably a honeycomb core, and unidirectional, fiberglass epoxy prepreg lamina are favored for each ply.