Provided are methods and devices for supporting of variety of different pre-cured composite stringers after forming and prior to curing. A post-forming processing device comprises a base with a channel for receiving hat portions of different stringers. The device also comprises a support structure, at least partially extending within the channel. The support structure is configured to conform to different hat portions and to retain the shape of these hat portions. For example, the support structure is made from a flexible material, which conforms to any shape variations. In some examples, the support structure is made from a jamming material that is reshaped together with each of the pre-cured composite stringers. A post-forming processing device is used for supporting different pre-cured composite stringers while various operations are performed on these stringers, such as stringer trimming, inspection, installation of bladders and noodles, and the like.

Systems and methods are provided for utilizing stringer end caps. One embodiment is a method of forming a stringer. The method includes laying up a stringer preform comprising fiber-reinforced material, placing the stringer preform onto a skin panel preform, bonding an end cap to the stringer preform and the skin panel preform, and co-curing the stringer preform and the skin panel preform while the end cap is bonded to the stringer preform and the skin panel preform, resulting in a composite part that includes the end cap.

Systems and methods are provided for fabricating composite parts. One embodiment is a method for fabricating a composite part. The method includes forming a skin panel preform comprising fiber reinforced material, disposing rigid end caps at the skin panel preform at end locations of stringer preforms that will be placed at the skin panel, locating the stringer preforms at the skin panel preform via the rigid end caps, and anchoring the stringer preforms to the skin panel preform.

Systems and methods for a caul plate for an irregular surface. One embodiment is a caul plate for co-curing or co-bonding a first composite part and a second composite part. A body of the caul plate includes a lower surface to face a top surface of the first composite part, a reference edge to locate the second composite part on the first composite part, and an upper surface that is opposite to the lower surface. The lower surface includes one or more bends to match one or more slopes in the top surface of the first composite part. The one or more bends correspond with ply changes in the first composite part.

A panel includes a corrugated base with base corrugations configured from first base segments and second base segments. A first of the base corrugations includes a first of the first base segments and a first of the second base segments that is non-parallel to the first of the first base segments. The first of the base corrugations forms a first channel that extends laterally between and longitudinally along the first of the first base segments and the first of the second base segments. A corrugated stringer includes a plurality of stringer corrugations arranged longitudinally along and within the first channel. The stringer corrugations are configured from first stringer segments and second stringer segments. A first of the stringer corrugations includes a first of the first stringer segments and a first of the second stringer segments that is non-parallel to the first of the first stringer segments.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a tapered shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The tips of the plurality of drop-off plies are arranged in a monotonically-inward pattern.

An improved composite stiffener and methods and tooling used to form the same. The stiffener includes one or more base flanges, a composite rod extending in an axial direction, a bulb cap surrounding the composite rod, and an upright web extending from the one or more base flanges to the base cap. The upright web includes a non-linear profile in the axial direction providing the improved lateral stiffness. The method includes providing tooling including a first compression tool extending in the axial direction and including a first web portion having a non-linear profile, and a second compression tool extending in the axial direction and including a second web portion having a non-linear profile. Plies are placed within the tooling and compressed such that at least a portion of plurality of plies are compressed in the web forming portion thereby forming a web of the bulb stiffener having a non-linear profile.

An aircraft wing has a plurality of wing segments mounted on a wing spar by joints that allow relative movement between the spar and the wing segments. Tuning of coefficients of thermal expansion is employed to reduce induced stresses from changes in temperature.

A panel assembly with a panel and a stringer is disclosed. The stringer has a stringer foot and an upstanding stringer web. The stringer foot has a flange which extends in a widthwise direction between the stringer web and a lateral edge and in a lengthwise direction alongside the stringer web, and a foot run-out which extends between the flange and a tip of the stringer foot. The foot run-out is bonded to the panel at a foot run-out interface. Reinforcement elements, such as tufts, pass through the foot run-out interface. At least some of the reinforcement elements are inclined relative to the foot run-out interface.

A stringer runout configuration has a pair of fittings with each fitting having a fitting web that is configured for attachment to a stringer web of a stringer on opposite sides of a terminating end of the stringer. The stringer web has a terminating end with a curved configuration and base flanges with rounded terminating ends. Each fitting has a base flange that has a bottom surface with a first surface area and a second surface area positioned at different heights. The first surface area of each of the fittings is configured for attachment to a stringer base flange on opposite sides of a terminating end of the stringer. The second surface area of each of the fittings is configured for attachment to a composite panel surface adjacent the terminating end of the stringer. These and other detailed design features described herein enhance the capability of the runout configuration.