Abstract: A disbond resistant multi-laminate composite product is provided having, a first member; a second member of composite material bonded to the first member; a third member of composite material bonded to at least the second member and being so positioned and arranged such that when the second and third members are stressed at least a portion of the third member will have higher stress than the adjacent second member. The third member preferably has a terminal portion adjacent the second member in which terminal portion the strain energy release rate is higher than in the adjacent second member when the second and third members are stressed. The second and third members are preferably so positioned and arranged such that the third member initiates delamination from the second member before the second member initiates delamination from the first member when the first, second and third members are under stress.

Abstract: A composite member having increased resistance to delamination includes a reinforcing wrap of fiber-matrix composite material which is encircled about the member so that the edge surfaces of the member are covered by the wrap. The wrap includes fibers which are oriented from about −60° to about +60° relative to the direction along which the reinforcing wrap is wrapped about the member. The fibers of the reinforcing wrap impart increased third-axis or Z-direction strength at the edges of the member where interlaminar tensile stresses are greatest.

Abstract: A composite member having increased resistance to delamination includes a reinforcing wrap of fiber-matrix composite material which is encircled about the member so that the edge surfaces of the member are covered by the wrap. The wrap includes fibers which are oriented from about −60° to about +60° relative to the direction along which the reinforcing wrap is wrapped about the member. The fibers of the reinforcing wrap impart increased third-axis or Z-direction strength at the edges of the member where interlaminar tensile stresses are greatest.

Abstract: A composite member having increased resistance to delamination includes a reinforcing wrap of fiber-matrix composite material which is encircled about the member so that the edge surfaces of the member are covered by the wrap. The wrap includes fibers which are oriented from about −60° to about +60° relative to the direction along which the reinforcing wrap is wrapped about the member. The fibers of the reinforcing wrap impart increased third-axis or Z-direction strength at the edges of the member where interlaminar tensile stresses are greatest.

Abstract: The present invention relates to an improved helicopter rotor system including a contoured flexure strap having a simplified geometrical configuration. The flexure strap serves to join the rotary hub assembly with the rotor blades and is formed of fiberglass. The primary load carrying fibers of the flexure strap preferably extend in the same direction as the spanwise axis of the flexure strap in order to withstand the centrifugal forces acting on the strap. The inboard end portion of the flexure strap includes two separate ends, with one of the ends extending in a vertically upward direction and the other end in a vertically downward direction. This allows the ends of flexure straps positioned on opposite sides of the rotary hub assembly to overlap one another and be retained in place by a single pin and bolt assembly.