Abstract: A fiber orientation verification system includes a sensor and an indicator to identify the fiber orientation within each sequentially laid composite material layer. The indicator projects visible indicator lines upon the lay-up surface which are indicative of a desired orientation for the composite material layer. The sensor and the indicator communicate with a computer module which contains a database including a detailed sequence to assure that each layer is proper placed. The operator is thereby provided with an exact location to lay-up each composite material layer and the proper fiber orientation of that layer. Continued verification is thus provided to the operator.

Abstract: A fiber orientation verification system includes a sensor and an indicator to identify the fiber orientation within each sequentially laid composite material layer. The indicator projects visible indicator lines upon the lay-up surface which are indicative of a desired orientation for the composite material layer. The sensor and the indicator communicate with a computer module which contains a database including a detailed sequence to assure that each layer is proper placed. The operator is thereby provided with an exact location to lay-up each composite material layer and the proper fiber orientation of that layer. Continued verification is thus provided to the operator.

Abstract: A composite spar for a helicopter rotor blade includes upper and lower side-wall regions and forward and aft conic regions wherein the conic regions further define transition and closure subregions. Constant width crossplies and unidirectional plies are stacked and arranged to form crossply and unidirectional laminates. The crossply laminates form the upper and lower sidewall regions and end portions thereof extend into the forward and aft conic regions to form a staggered distribution of structural joints and slip plane interfaces therein. The crossply laminates are comprised of high modulus fibers which are oriented within a range of .+-.42.degree. to about .+-.38.degree. relative to the longitudinal axis of the composite spar. The unidirectional laminates form the upper and lower sidewall regions and have end portions extending into the transition subregions.

Abstract: An expandable spar filler block device for use in combination with a spar member of an articulated main rotor assembly of a helicopter. A preferred embodiment of the device includes first and second filler members and an expansion mechanism. Each filler member includes a spar engagement surface that is complementary to the inner mold line (IML) surfaces of the spar member and first and second tapered surfaces. The expansion mechanism for the preferred embodiment of the expandable spar filler block device is a pull shim that includes a first segment and a constant tapered segment having tapered surfaces that are complementary to the first tapered surfaces of the filler members.

Abstract: A replaceable tip portion (20) for a helicopter rotor blade (14) is selectively swept, tapered and anhedral. The tip portion is formed of an upper and lower composite tip skin layer (35), each tip skin layer having bonded thereto a honeycomb core (38). The density of the core varies from a leading edge of the tip to a trailing edge of the tip from a high density to a lower density. A channel (recess) (40) is formed in the honeycomb for receiving a rotor spar tip end (30), and the tip portion is removably attached (60) to the rotor spar and the remainder of the rotor blade. The honeycomb core is attached to the upper and lower tip skin layers in halves, and is machined along the rotor blade chord plane (70) prior to assembly of the halves on the rotor spar, the machined core providing tight tolerance control in the construction of the blade tip portion.

Abstract: A rotor blade balance weight assembly comprises a weight retention housing (10) having a hollow core (22) and being closed on one end (12). The housing is disposed in an aperture which extends from the upper (52) to the lower (53) airfoil surfaces of the rotor blade (50). The closure end of the housing is contoured to match the airfoil upper surface contour. A stud (70) extends along the central axis of the housing, and washer-like balance weights (72) are received over the stud and secured by a locking nut (75). The open end of the housing is closed by a cover plate (25) that is contoured to match the airfoil lower surface contour, the cover plate being secured to the housing by a nut (78) in locking engagement with the stud. A pair of clips (37) are received within the housing, each clip having a tab surface (40) which extends through slots (42) in the housing, the clips being secured by the locking nut and stud.