Abstract: An apparatus is provided for locating holes to be drilled in a post-cure composite structure, generally comprising a drill boss defining a bore, a bonding fixture defining at least one hole, wherein one surface of the bonding fixture defines the shape of the composite structure to be formed, and the opposing surface thereto engages the drill boss such that the drill boss is aligned with respect to the hole through the bonding fixture. A drill bushing defining a bore is further concentrically disposed within the hole in the bonding fixture and the drill boss bore such that a hole can be drilled in the composite structure by inserting a drill bit through the drill boss bore and the drill bushing bore. In addition, the drill bushing extends between the hole in the bonding fixture and the drill boss bore, wherein the drill bushing bore is adapted to receive a drill bit of a predetermined size for drilling the hole in the composite structure.

Abstract: To virtually eliminate core crush in honeycomb sandwich structure for fixed leading edge panels, I rearrange the order of the plies. I use a full surface, facing ply of woven fabric impregnated with resin adjacent the core. This ply passes over an erosion strip at the part margin while lower plies terminate at the erosion strip. The facing ply is in contact with substantially the entire surface of the core along the entire skin-core interface to prevent slipping of the skin relative to the core during curing. I orient the facing ply 0/90.