Abstract: A hollow composite airfoil with an integral internal support rib of fluoroelastomer rubber is formed by bracketing the rib between two silicone rubber mandrels to form a core assembly having a desired aerodynamic shape, then building up on opposite sides of the core assembly separate stacks of laminae of a composite material of graphite (or carbon) and glass fibers impregnated with an epoxy resin, with the two stacks overlapping adjacent to the leading and trailing edges of the core assembly. Heat and pressure are then applied to the core assembly with the laminae thereon to bond together the laminae of each stack, then to bond the two stacks together along the overlapping portions thereof and to bond the two stacks to the rib to form a continuous shell around the core assembly. The mandrels are then removed. One open end of the resulting hollow airfoil is plugged and that end is inserted into a recess in a mounting platform with a predetermined clearance space therebetween.

Abstract: A composite fabric preform and article made of both structural and thermoplastic fibrous materials and a method of making such preform and article, the method improving the handling properties of the composite. A plurality of layers of fabric made from structural fibrous material are disposed in a stacked assembly with layers sequentially adjacent each other. At least each of alternate layers of the alternate layers of fabric include within its weave thermoplastic fibrous material intermixed with the structural fibrous material. The layers of fabric, preferably under pressure, are heated at a temperature sufficient to promote bonding action by the thermoplastic fibers at junctures between fibrous materials.

Abstract: A composite fabric preform and article made of both structural and thermoplastic fibrous materials and a method of making such preform and article, the method improving the handling properties of the composite. A plurality of layers of fabric made from structural fibrous material are disposed in a stacked assembly with layers sequentially adjacent each other. At least each of alternate layers of the alternate layers of fabric include within its weave thermoplastic fibrous material intermixed with the structural fibrous material. The layers of fabric, preferably under pressure, are heated at a temperature sufficient to promote bonding action by the thermoplastic fibers at junctures between fibrous materials.

Abstract: A variable pitch blade and blade mount which is suitable for propellers, fans and the like and which has improved impact resistance. The invention is particularly directed to composite fan blades and blade mounting arrangements wherein the blades are permitted to pivot relative to a turbine hub about an axis generally parallel to the centerline of the engine upon impact of a large foreign object, such as a bird. By thus providing for the pivoting of the blades upon impact, centrifugal force recovery becomes the principal energy absorbing mechanism and a blade having improved impact strength is obtained.

Abstract: A turbomachinery blade platform comprising a pair of complementary platform halves, each having an outer flow path defining shroud adapted to extend generally laterally of the blade. An inner flange on each platform half, also extending generally laterally of the blade, is retained in a cooperating slot formed within the support structure retaining the blade. A structural member extending between the shroud and the flange is contoured to conform to an overlapping wedging surface disposed about the blade airfoil surface. The platform is thus provided with redundant retention by both the blade and by the blade support structure.