Abstract: A helicopter main rotor blade balance weight retention system and assembly having a base plate (105), at least one support post (107) integral with the base plate and extending out perpendicularly from the base plate, a plurality of balance weights (109), a retaining nut plate (111), and one or more fastening bolts (113) for securing the balance weights to the base plate, and the base plate to the rotor blade. The balance weights (109) include apertures (117, 119) through which the support posts and the fastening bolts pass. The apertures through which the support posts pass are dimensioned such that the a snug fit is formed between the support posts and the balance weight; but the apertures through which the fastening bolts pass are dimensioned such that the threaded portions of the fastening bolts are not subjected to any shear loads from the balance weights due to the centrifugal force generated by the rotating rotor blades. The weight retention assembly is installed into pockets in the blade tip.

Abstract: A helicopter main rotor blade balance weight retention system and assembly having a base plate (105), at least one support post (107) integral with the base plate and extending out perpendicularly from the base plate, a plurality of balance weights (109), a retaining nut plate (111), and one or more fastening bolts (113) for securing the balance weights to the base plate, and the base plate to the rotor blade. The balance weights (109) include apertures (117, 119) through which the support posts and the fastening bolts pass. The apertures through which the support posts pass are dimensioned such that the a snug fit is formed between the support posts and the balance weight; but the apertures through which the fastening bolts pass are dimensioned such that the threaded portions of the fastening bolts are not subjected to any shear loads from the balance weights due to the centrifugal force generated by the rotating rotor blades. The weight retention assembly is installed into pockets in the blade tip.

Abstract: An improved feathering flexure for a helicopter rotor system yoke includes, in transverse cross section, a relatively thin central web and six relatively thin flanges. Three flanges extend from each of the web's two edges, and the flanges lie in planes which are approximately radial relative to the neutral feathering axis of the feathering flexure. The feathering flexure is constructed of fiberglass material embedded in a polymer matrix. The web's fiberglass material in the web is bias material, that is, material whose glass fibers are oriented at plus or minus 45 degrees relative to the yoke's spanwise axis. In transverse cross section, each of the flanges includes two unidirectional belts disposed on either side of a bias pack. The glass fibers in the unidirectional belts are oriented parallel to the yoke's spanwise axis. The fiberglass material in the bias packs is bias material.