Abstract: A two-stage co-cure method for fabricating a composite article having a box-beam cross-sectional configuration wherein an outer shell portion of the composite article is fabricated and configured in the first stage to function as the tooling for completing the fabrication of composite article in the second stage.

Abstract: The method of fabricating selectively shaped dog-leg plies of composite material comprising unidirectionally extending high tensile strength fibers or filaments extending for the full length of the ply and embedded in a resin matrix comprising winding high tensile strength filament onto a mandrel of generally cylindrical shape but having circumferentially extending frustoconical projections extending radially therefrom so that the filament wound onto the cylindrical portion of the mandrel forms the straight legs of the dog-leg ply and so that the filament wound on the frustoconical projection of the mandrel form the arcuate central portion of the dog-leg ply.

Abstract: A method for resin transfer molding composite articles of complex configuration that have high fiber-to-resin ratios. The molding apparatus includes a compliant mold subassembly having one or more conformable cauls and a complementary, non-permeable membrane that function, in combination, as a semi-rigid molding tool. The compliant mold subassembly is relatively insensitive to bulk variations of layed-up fiber reinforcement material, facilitating fiber reinforcement material lay up and closure of the molding apparatus. The compliant mold subassembly provides uniform pressures during various molding stages, i.e., resin injection, expulsion of excess resin, curing, to enhance the homogeneity and dimensional stability of the finished composite article. The semi-rigid aspect of the compliant mold subassembly facilitates demolding of the finished composite article.

Abstract: A method of making tubular composite structures that simplifies vacuum bag sealing. The method comprises disposing a prepreg structure within a tool that has at least one hole. The prepreg is disposed adjacent a mandrel. The mandrel comprises an inner bag containing a solid filler core that comprises about 75% to about 95% of the volume of the inner bag. The hole is enclosed with a vacuum bag thereby forming a void space between said vacuum bag and said prepreg. The void space is evacuated. The vacuum bag applies a predetermined pressure to the inner bag thus causing the inner bag to apply a substantially uniform predetermined pressure to the surface of the prepreg. The prepreg is exposed to heat.