Abstract: A method of constructing a mandrel generally complementary to a spar cavity of a spar includes connecting a first component and a second component to form a central space there between and inserting a center component within the central space such that the center component retains the first component and second component in a desired position forming an outer surface of the mandrel which corresponds to an inner surface of the spar cavity.

Abstract: A method of constructing a mandrel generally complementary to a spar cavity of a spar includes connecting a first component and a second component to form a central space there between and inserting a center component within the central space such that the center component retains the first component and second component in a desired position forming an outer surface of the mandrel which corresponds to an inner surface of the spar cavity.

Abstract: A mandrel for use in manufacturing a spar having a spar cavity is provided including a first component, a second component, and a center component. The first component is configured to define at least an interior first surface of the spar cavity. The second component is configured to define at least an interior second surface of the spar cavity and form a space between the first and second components. The second component has a second side arranged in contact with a first side of the first component. The center component is arranged within the space to separate the first and second components and to engage at least a portion of each of the first and second components to retain the first and second components in a desired position.

Abstract: A weight training device comprising a hollow tubular body. A plurality of handle wells disposed in the hollow tubular body. A plurality of handles disposed in the handle wells, wherein the plurality of handles comprise axially-oriented handles and circumferentially-oriented handles, and wherein the axially-oriented handles are diametrically opposed to the circumferentially-oriented handles. A fill cap well disposed in the hollow tubular body. A fill cap disposed in the fill cap well and removably attached to the hollow tubular body, wherein the fill cap is threaded and is attached to a threaded extrusion of the hollow tubular body. A plurality of baffles disposed within the hollow tubular body, wherein the hollow tubular body is configured to be used partially filled with a fill material so as to create a randomly variable weight distribution. Two diametrically-opposed end caps are attached to the axial ends of the hollow tubular body.

Abstract: A weight training device comprising a hollow tubular body. A plurality of handle wells disposed in the hollow tubular body. A plurality of handles disposed in the handle wells, wherein the plurality of handles comprise axially-oriented handles and circumferentially-oriented handles, and wherein the axially-oriented handles are diametrically opposed to the circumferentially-oriented handles. A fill cap well disposed in the hollow tubular body. A fill cap disposed in the fill cap well and removably attached to the hollow tubular body, wherein the fill cap is threaded and is attached to a threaded extrusion of the hollow tubular body. A plurality of baffles disposed within the hollow tubular body, wherein the hollow tubular body is configured to be used partially filled with a fill material so as to create a randomly variable weight distribution. Two diametrically-opposed end caps are attached to the axial ends of the hollow tubular body.

Abstract: A weight training device comprising a hollow tubular body. A plurality of handle wells disposed in the hollow tubular body. A plurality of handles disposed in the handle wells, wherein the plurality of handles comprise axially-oriented handles and circumferentially-oriented handles, and wherein the axially-oriented handles are diametrically opposed to the circumferentially-oriented handles. A fill cap well disposed in the hollow tubular body. A fill cap disposed in the fill cap well and removably attached to the hollow tubular body, wherein the fill cap is threaded and is attached to a threaded extrusion of the hollow tubular body. A plurality of baffles disposed within the hollow tubular body, wherein the hollow tubular body is configured to be used partially filled with a fill material so as to create a randomly variable weight distribution. Two diametrically-opposed end caps are attached to the axial ends of the hollow tubular body.

Abstract: A main rotor blade includes a tip section having a splice cap, a structural tip spar, a core and an upper and lower tip skin. The tip section is mounted to a central blade section by mounting the tip spar to a main blade spar. The tip spar includes a first surface substantially parallel to a second surface. The first and second surfaces each extend from a shear web therebetween to define the generally C-shape in cross section. The shear web generally carries rotor blade torsional loads and eliminates the heretofore required structural core. A section of the tip spar overlaps a section of the main blade spar. The tip section thereby transfers the loads carried thereby through interaction between the overlapped spar sections. The tip section core and skins need not be structural members as the tip spar carries rotor blade tip section torsional loads.

Abstract: A composite tip cap assembly for a helicopter main rotor blade includes a composite main fairing, a unitary composite rib detail internally integrated in combination with the composite main fairing, a composite closure fairing bonded in combination with the composite main fairing, and an abrasion strip bonded in combination with the composite main fairing and the composite closure fairing.

Abstract: An apparatus for installing a leading-edge sheath onto a helicopter main rotor blade subassembly, including a lower assembly having a leading-edge sheath contour nest configured for supporting the leading-edge sheath, opposed carriage members connected to a base, wherein each of the opposed carriage members supports a plurality of suction cups and is capable of synchronized translational movement relative to the leading-edge sheath contour nest between an engaged position wherein the plurality of suction cups are in abutting engagement with the leading-edge sheath, and a disengaged position where the plurality of suction cups are disengaged from the leading-edge sheath.

Abstract: An apparatus for assembling a helicopter main rotor blade subassembly which includes a lower airfoil skin, a core, an upper airfoil skin, and a spar assembly having a tip end and a root end, the apparatus including a lower assembly including a base having a contoured upper airfoil nest, wherein the contoured upper airfoil nest has a root end and a tip end, at least two guide ramps disposed proximal to the contoured upper airfoil nest, wherein at least one of the guide ramps is disposed proximal to the root end and at least one of the guide ramps is disposed proximal to the tip end, and a plurality of leading-edge pusher cams disposed proximal to the contoured upper airfoil nest.

Abstract: A method for fabricating a helicopter blade subassembly includes the steps of providing a blade compaction apparatus having a lower assembly configured for mating with an upper assembly. The lower assembly includes a base having a contoured upper airfoil nest with at least two guide ramps and a plurality of leading-edge pusher cams disposed proximal thereto. The upper assembly includes a support structure supporting a flexible impervious membrane, wherein the flexible impervious membrane and the contoured upper airfoil nest define a molding cavity therebetween upon mating of the upper assembly to the lower assembly. The method further includes disposing the upper airfoil skin and the core in combination with the contoured upper airfoil nest, and then connecting a tip end support insert and a root end support insert in combination with the spar assembly, wherein each of the support inserts include guide members.

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: A fiberglass or other material skin is applied to a composite airfoil structure in a mold assembly having a partially compliant caul plate component which defines the shape of the lower surface of the airfoil. The caul plate component includes a first portion which is essentially rigid and which covers the leading edge of the airfoil. The rigid portion of the caul plate component provides improved conformation of the airfoil skin to the leading edge of the airfoil. The caul plate component also includes a compliant portion which covers and defines the shape of the trailing edge of the lower surface of the airfoil. The stiffness of the caul plate component also has a variable stiffness zone which interconnects the rigid and compliant portions thereof.

Abstract: The described embodiment of an edge-of-part (EOP) scribe device is operative to simultaneously scribe opposed trim lines in an oversized, cured leading-edge sheath mounted on a sheath mold assembly. The EOP scribe device includes a primary carriage assembly having rollers secured thereto wherein the primary carriage assembly is translatable along side rails secured to the sheath mold assembly, opposed pairs of guide rails affixed to the primary carriage assembly, and a secondary carriage assembly mounted in movable combination with each pair of guide rails. Each secondary carriage assembly includes a spring-loaded scribe head for inscribing a trim line in the cured leading-edge sheath, a rigid follower linkage secured to the secondary carriage assembly, and a follower slide roller mounted in rotatable combination with the rigid follower linkage and operative to rotatably engage a trim line template mounted on the sheath mold assembly.

Abstract: Apparatus and methods for fabricating a helicopter main rotor blade include a compaction fixture for assembling and compacting blade subassembly components and a sheath spreading/insertion apparatus for spreading and inserting a leading-edge sheath onto the blade subassembly during the compaction process. The compaction fixture includes a lower assembly having a contoured upper airfoil nest mounted in combination with a support structure and an upper assembly having a pressure bag affixed in sealed combination to a contoured backplate affixed in combination to a structural support truss. The contoured upper airfoil nest includes a plurality of tooling pins for locating an upper composite skin in aligned combination on the contoured upper airfoil nest and a plurality of pusher pins for chordwise alignment of a spar assembly in the contoured upper airfoil nest. Spar stanchions affixed to the support structure provide spanwise alignment of the spar assembly in the contoured upper airfoil nest.

Abstract: A method for fabricating a helicopter main rotor blade includes a compaction fixture for assembling and compacting blade subassembly components and a sheath spreading/insertion apparatus for spreading and inserting a leading-edge sheath onto the blade subassembly during the compaction process. The compaction fixture includes a lower assembly having a contoured upper airfoil nest mounted in combination with a support structure and an upper assembly having a pressure bag affixed in sealed combination to a contoured backplate affixed in combination to a structural support truss. The contoured upper airfoil nest includes a plurality of tooling pins for locating an upper composite skin in aligned combination on the contoured upper airfoil nest and a plurality of pusher pins for chordwise alignment of a spar assembly in the contoured upper airfoil nest. Spar stanchions affixed to the support structure provide spanwise alignment of the spar assembly in the contoured upper airfoil nest.

Abstract: A fiberglass or other material skin is applied to a composite airfoil structure in a mold assembly having a partially compliant caul plate component which defines the shape of the lower surface of the airfoil. The caul plate component includes a first portion which is essentially rigid and which covers the leading edge of the airfoil. The rigid portion of the caul plate component provides improved conformation of the airfoil skin to the leading edge of the airfoil. The caul plate component also includes a compliant portion which covers and defines the shape of the trailing edge of the lower surface of the airfoil. The stiffness of the caul plate component also has a variable stiffness zone which interconnects the rigid and compliant portions thereof.

Abstract: The rotor blades of a helicopter are balanced both in the chordal direction and in the spanwise direction in a static balancing assembly. The assembly includes a support surface on which there are four weighing scales. The scales are positioned in close proximity with the four corners of the rotor blade. The scales provide four cooperating pairs of blade spanwise and chordwise balancing reference data. The scales are operably connected to a microprocessor which is preprogrammed with desired balance data for the blades being tested. Deviations from the desired balance data detected by the scales and the microprocessor are corrected by selectively adding or subtracting weight on the blades at appropriate locations of the surfaces thereof.

Abstract: A method for fabricating a helicopter main rotor blade includes a compaction fixture for assembling and compacting blade subassembly components and a sheath spreading/insertion apparatus for spreading and inserting a leading-edge sheath onto in combination with the blade subassembly during the compaction process. The compaction fixture includes a lower assembly having a contoured upper airfoil nest mounted in combination with a support structure and an upper assembly having a pressure bag affixed in sealed combination to a contoured backplate affixed in combination to a structural support truss. The contoured upper airfoil nest includes a plurality of tooling pins for locating an upper composite skin in aligned combination on the contoured upper airfoil nest and a plurality of pusher pins for chordwise alignment of a spar assembly in the contoured upper airfoil nest. Spar stanchions affixed to the support structure provide spanwise alignment of the spar assembly in the contoured upper airfoil nest.

Abstract: An apparatus for fabricating a helicopter main rotor blade includes a compaction fixture for assembling and compacting blade subassembly components and a sheath spreading/insertion apparatus for spreading and inserting a leading-edge sheath onto in combination with the blade subassembly during the compaction process. The compaction fixture includes a lower assembly having a contoured upper airfoil nest mounted in combination with a support structure and an upper assembly having a pressure bag affixed in sealed combination to a contoured backplate affixed in combination to a structural support truss. With the upper and lower assemblies in locked combination, the pressure bag is pressurized to compact the assembled blade subassembly components. The sheath spreading/insertion apparatus includes a movable stanchion, upper first and lower second elongate carriage members mounted in synchronized movable combination with the stanchion, and a row of suction cups mounted in combination with each carriage member.