Systems and methods are provided for composite part design. One embodiment is an apparatus that designs a composite part. The apparatus includes a controller configured to generate a design for the part. The controller subdivides the part into blocks that each comprise a contiguous stack of layers within the part, identifies rules that constrain how layers that have different fiber orientations are stacked within the part, generates a guide for a block that prescribes a fiber orientation for each layer of the block, and identifies sublaminates comprising that are compatible with the guide for the block. The controller subdivides the part into panels, and selects one of the compatible sublaminates for one of the panels of the block, based on compatible sublaminates for neighboring panels. The apparatus also includes a memory configured to store the design for use by an Automated Fiber Placement (AFP) machine constructing the part.

In one aspect, there is an engagement member for splicing a spar assembly in an aircraft wing including a joining portion having a first attachment for connecting to a first spar and a second attachment surface for connecting to a second spar; and a rib post extending from the joining portion and disposed between the first attachment surface and the second attachment surface. In an embodiment, the rib post is integral to the joining portion and is configured to couple with a rib web.

Systems and methods are provided for composite part design. One embodiment is a method for selectively analyzing feasibility of optimizing fiber orientations for layers of a multi-layer composite part subdivided into panels that each comprise a fraction of an area of the composite part. The method includes identifying stacking sequence rules that constrain the composition of sublaminates that comprise consecutively stacked layers utilized during optimization, for each panel of the composite part, analyzing the panel by identifying ply counts that constrain a number of plies at the panel, selecting a number of sublaminates to utilize during optimization of the panel, calculating ply count ranges for a laminate, based on the number of sublaminates and the stacking sequence rules, and determining whether the ply counts for the panel comply with the ply count ranges for the laminates.

A wing assembly include at least one fuel tank having a tank outboard end. In addition, the wing assembly includes a stout wing rib located proximate the tank outboard end and extending between a front spar and a rear spar. The wing assembly also includes at least one outboard wing rib located outboard of the stout wing rib and defining an outboard wing bay. The wing assembly also includes an upper skin panel and a lower skin panel each coupled to the front spar, the rear spar, the stout wing rib, and the outboard wing rib. A plurality of bead stiffeners are coupled to the upper skin panel and/or the lower skin panel and are spaced apart from each other within the outboard wing bay.

Systems and methods are provided for composite part design. One embodiment is a method of creating a library of sublaminates used in optimizing fiber orientations of a multi-layer composite part subdivided along its depth into panels that each comprise a fraction of the area of the composite part. The method includes creating sublaminates that each comprise consecutively stacked layers having a unique sequence of fiber orientations, checking the sublaminates for compliance with stacking sequence rules that constrain how fiber orientations are sequenced, and removing sublaminates that do not comply with the stacking sequence rules. The method further includes generating new sublaminates that each include an additional layer, by, for each of multiple fiber orientations: selecting a sublaminate that was not remove, and generating a new sublaminate by appending an additional layer having the fiber orientation to the selected sublaminate.

A panel is disclosed, including a first facesheet, a second face sheet, and a plurality of pultrusion-formed web structures. Each web structure has a middle support portion, a first end portion, and a second end portion. The first end portion of each web structure is attached to the first facesheet and the second end portion of each web structure is attached to the second facesheet. The middle support portion, first end portion, and second end portion of each web structure form a single monolithic structure.

A composite structure includes a first composite material, a second composite material bonded to the first composite material, and a corner fillet part provided at a corner part formed by the first composite material and the second composite material. In the composite structure, the rigidity of the corner fillet part is adjustable, and a pull-off stress to be applied to the corner part is adjusted by adjusting the rigidity of the corner fillet part. The pull-off stress to be applied to the corner part is adjusted to be decreased by adjusting the rigidity of the corner fillet part to be decreased.

A core stiffened panel includes first and second skins having a large cell core and a solid insert joined therebetween. The solid insert has a side surface at least a portion of which is adjacent to the large cell core and may be joined to the large cell core. The first skin, the second skin and the solid insert may be formed from composite materials such as carbon composite materials and preferably have generally matching coefficients of thermal expansion.

An airframe assembly for an aircraft includes a first airframe member having first and second skins with a large cell core and a solid insert joined therebetween. The solid insert has a side surface at least a portion of which is adjacent to the large cell core. The first airframe member has a first set of openings extending through the first skin, the solid insert and the second skin. The airframe assembly also includes a second airframe member having a second set of openings operable to be aligned with the first set of openings of the first airframe member. Each of a plurality of fasteners extends through one of the openings of the first set of openings and one of the openings of the second set of openings securably coupling the first airframe member to the second airframe member.

A bladder mandrel package, used to manufacture a composite structure, includes a mandrel and a wrap ply, surrounding the mandrel to form a wrapped mandrel. The bladder mandrel package also includes a first radius filler, coupled to the wrap ply at a first radius of the wrapped mandrel, and a second radius filler coupled to the wrap ply at a second radius of the wrapped mandrel. The mandrel, the wrap ply, the first radius filler, and the second radius filler are consolidated to from the bladder mandrel package.