A structural assembly including a first member having an external side and an internal side, the first member defining a first member through-bore, a second member having an external side and an internal side, the second member defining a second member through-bore aligned with the first member through-bore, and a mechanical fastening system including a bushing at least partially received in the first member through-bore, the bushing defining a bushing through-bore and including a flange, wherein the flange is positioned in a gap between the internal side of the first member and the external side of the second member, a nut plate connected to the internal side of the second member, the nut plate defining a clearance bore aligned with the second member through-bore and the bushing through-bore, the nut plate including a nut, and a bolt extending through the bushing through-bore and into threaded engagement with the nut.

A rib is disclosed for use in a torque box of a wing structure provided on an aircraft. The wing structure has a skin panel and a stringer coupled to the skin panel. The rib includes a web defining at least one stringer hole sized to receive the stringer, a shear tie coupled to the web and configured to engage the skin panel, and a clip positioned adjacent the at least one stringer hole. The clip has a base coupled to and aligned with the web, a head extending at an angle relative to the base and configured to engage the stringer, and a transition portion extending between the base and the head.

Described herein are stringer assemblies, such as blade stringers, and methods of forming thereof. A stringer assembly comprises a first fabric composite stiffener, a second fabric composite stiffener, and an intermediate tape composite stiffener, disposed between and connected to each of the first and second stiffeners. Using three separate components allows forming sharp bends, eliminating voids and gap fillers, and adding new features, such as edge reinforcements. Each of the first and second fabric composite stiffeners comprises a web portion, a flange portion, and a curved portion, positioned between the web and flange portions. The web portions surround and are attached to the intermediate tape composite stiffener and, in some examples, include tapered-out edges for additional rigidity. The flange portions are attached to the composite base. The curved portions conform to the flared-out edges of the intermediate tape composite stiffener, which extends and connects to the composite base.

Additive manufactured airframe structure having a plurality of additive manufactured airframe segments operable to be linked together in an assembled direction. Each of the plurality of additive manufactured airframe segments are separate from one another in an unassembled configuration. Plurality of reinforcement elements operable to be received in a receiving portion of the plurality of airframe segments and extending through the plurality of airframe segments in a normal direction. Receiving portion is located on the interior of a respective one of the plurality of airframe segments.

Examples include an apparatus configured for attaching a rib of an aircraft wing to a panel of the aircraft wing, the apparatus including: an insert that is configured to be attached, via an interference fit, to a hole in the rib; a shear tie including a socket at a first end of the shear tie, where the shear tie is configured to be attached to the panel at a second end of the shear tie; a ball stud including a shaft and a ball that is opposite the shaft, where the shaft is configured to be attached to the insert and the ball is configured to be positioned within the socket; and a fastener that is configured to secure the ball within the socket, thereby attaching the ball stud to the shear tie.

A seal for sealing an aircraft fuel tank, an aircraft wing rib and stringer sealing assembly, an aircraft wing fuel tank, an aircraft structural wing box, an aircraft wing, and a method of sealing an aperture are disclosed. The seal is for sealing a wing rib to a stringer passing through an aperture in the rib at a variable position in the aperture. The seal includes self-adjustment means to absorb any tolerance when forming the seal, upon the stringer being assembled into the aperture in the rib.

A method and apparatus are presented. The apparatus comprises a first unitary structure, a second unitary structure, and a number of joints between the first unitary structure and the second unitary structure. The first unitary structure has a plurality of T-shaped cross-sections. The second unitary structure has a plurality of T-shaped cross-sections.

A method and apparatus for compacting composite stringers. In one illustrative embodiment, an apparatus comprises a compacting structure, a compactor vacuum system, and a carrier vacuum system. The compacting structure has a shape configured to contact layers of uncured composite material for a composite stringer. The compactor vacuum system is associated with the compacting structure. The compactor vacuum system is configured to cause the compacting structure to apply a pressure to the layers of uncured composite material when a compactor vacuum is applied to the compactor vacuum system. The carrier vacuum system is associated with the compacting structure. The carrier vacuum system is configured to hold the layers of uncured composite material against the compacting structure when a carrier vacuum is applied to the carrier vacuum system.

A composite stiffener for a stiffener reinforced panel is disclosed. The stiffener has a longitudinal direction and a run-out region which terminates at an end of the stiffener. The stiffener also has a constant section region inboard of the run-out region in the longitudinal direction and having a constant cross section transverse to the longitudinal direction with a crown between adjacent foot portions. The run-out region has a changing cross section transverse to the longitudinal direction with a crown between adjacent foot portions and the crown reduces in height towards the end of the stiffener forming a ramp. The composite stiffener includes a number of blankets of non-crimp fabric layers.

An aircraft includes a wing having a first upstream longeron and a second downstream longeron extending in the direction of the span of said wing, and at least one propulsion unit supported by the wing. The propulsion unit includes a turboprop engine and a propeller. The propeller includes an external annular casing fixed to a suction surface of the wing, and at least to the first upstream longeron via at least one first and second fastener.