The invention provides a firefighting float plane having a fuselage and two floats mounted to the fuselage. The fuselage has a water tank with open and closed configurations. In some embodiments, the water tank is integrated into the fuselage, and/or both the water tank and the fuselage have a generally triangular cross-sectional configuration. The water tank has a closed bottom in its closed configuration and an open bottom in its open configuration. In some embodiments, the plane has specified ratio of water tank holding capacity to total power of two engine assemblies. It can optionally also have the above-noted fuselage configuration, tank configuration, or both. In some embodiments, the plane has dual propellers, two engine assemblies, and two tail booms, optionally together with specified ratio of water tank holding capacity to total power of two engine assemblies. It may also have the above-noted fuselage configuration, tank configuration, or both.

Methods and systems are provided for fabricating a composite structure. In one example, the composite structure may include a honeycomb core sandwiched between face sheets. An edge of the honeycomb core may be abraded and a top face sheet may be perforated. As such, a likelihood of delamination of the composite structure during a curing step may be reduced.

A composite door comprises a composite frame, which comprises a first rail, a second rail, and crossbeams, joining the first rail and the second rail. The composite door also comprises a first composite side beam, a second composite side beam, and a composite skin, connected to each of the crossbeams of the composite frame, to the first composite side beam, and to the second composite side beam. The composite door further comprises first composite edge fittings, each connected to a corresponding one of the crossbeams of the composite frame, to the first composite side beam, and to the composite skin, and second composite edge fittings, each connected to a corresponding one of the crossbeams of the composite frame, to the second composite side beam, and to the composite skin.

Provided is a multilayer composite that has flame retardancy and low smoking property as well as has high physical characteristics. The multilayer composite has a multilayer structure and includes at least one core layer and at least one skin layer, wherein the multilayer composite satisfies all the following conditions (A) to (D): (A) the core layer is a composite including discontinuous reinforcing fibers and a first thermoplastic resin, in which the discontinuous reinforcing fibers are randomly dispersed and bonded with the first thermoplastic resin at least at intersections of the discontinuous reinforcing fibers; (B) the skin layer is a composite including continuous reinforcing fibers and a second thermoplastic resin, in which the continuous reinforcing fibers are impregnated with the second thermoplastic resin; (C) each of the first and the second thermoplastic resins has a limiting oxygen index of 30 or higher; and (D) the first and the second thermoplastic resins are miscible with each other.

A system includes a mandrel contoured to define a tapering tubular shape of a workpiece cured on the mandrel and a demolding tool. The demolding tool is configured to remove the workpiece from the mandrel after the workpiece is cured on the mandrel and cut longitudinally. The demolding tool is configured to remove the workpiece from the mandrel by deforming a first end of the workpiece to at least partially disengage the first end of the workpiece from a first end of the mandrel, and subsequently, deforming a second end of the workpiece to at least partially disengage the second end of the workpiece from a second end of the mandrel. The first end of the workpiece may have a first cross-sectional area that is smaller than a second cross-sectional area of the second end of the workpiece.

Systems and methods are provided for hardening wing panel preforms. One embodiment is a method for fabricating a wing panel for an aircraft. The method includes loading a wing skin preform onto a contour of an Outer Mold Line (OML) tool, applying stringer preforms to troughs of an Inner Mold Line (IML) tool, aligning the OML tool with the IML tool, and assembling the IML, tool and the OML tool into a cartridge that molds a wing panel preform comprising the wing skin preform and the stringer preforms. The method further includes inserting the cartridge into a press, and hardening the wing panel preform into a composite part while the cartridge resides in the press.

An aircraft structure which extends along a longitudinal axis, a lateral axis and a vertical axis, wherein the aircraft structure includes an upper shell and a lower shell that together surround an interior compartment designed for accommodating an aircraft cabin, and a pillar arrangement with at least one support pillar which extends through the interior compartment and connects the upper shell to the lower shell and supports same in relation to each other. An aircraft structure can be provided which is particularly efficient, in particular has a low weight and requires little space and outlay on assembly is achieved in that the interior of the support pillar has at least one flow duct for the conduction of air-conditioned air.

A composite structure including a multi-layer laminate having a plurality of regions each oriented out of plane relative to an adjacent region, and each extending in a longitudinal dimension of the multi-layer laminate, wherein the multi-layer laminate includes at least one ply layer having an oblique fiber orientation relative to the longitudinal dimension, and wherein the at least one ply layer includes a first section and a second section each having a side edge, the first and second sections aligned side-by-side such that a first interface defined between the respective side edges is oriented to extend in the longitudinal dimension.

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 filler preform in a wedge form includes reinforcing fiber bundles consisting of reinforcing fiber filaments, wherein the filaments are directed parallel to each other within the fiber bundle, wherein the fiber bundle contains a first resin composition in a concentration in the range from 1 to 10 wt. % relative to the fiber weight, wherein the fiber bundles have a length in the range from 2 to 20 mm and at least 60% of the fiber bundles are reversibly fixed in a curved form within the wedge filler preform whereby flanks of the curved fiber bundles create an opening angle of less than 120° and the opening angle of the curved fiber bundles relates with an opening angle of the wedge form of the wedge filler preform. A method for producing the wedge filler preform and a method for producing a reinforcing fiber composite include a filler perform.