A composite spring made of a wire of a longitudinal axis curved around a spring axis in a winding direction and a method of fabrication thereof, the spring, the wire comprising a core; and fibers layers wound around the core, and an angular positioning, relative to the spring axis, of each one of the fiber layers being selected, along a length of the core, depending on the winding direction of the wire about the spring axis, to adjust at least one of: high natural frequency of the spring, resistance to buckling and resistance to tensile and compressive stress components induced by a compressive load on the spring.

A composite spring made of a wire of a longitudinal axis curved around a spring axis in a winding direction and a method of fabrication thereof, the spring, the wire comprising a core; and fibers layers wound around the core, and an angular positioning, relative to the spring axis, of each one of the fiber layers being selected, along a length of the core, depending on the winding direction of the wire about the spring axis, to adjust at least one of: high natural frequency of the spring, resistance to buckling and resistance to tensile and compressive stress components induced by a compressive load on the spring.

In one aspect, a seal case is provided for a roller bearing assembly having a central axis. The seal case includes an annular first end section including a rim configured to engage an outer ring, an intermediate section including a radial wall extending inwardly from the first end section and an axial wall extending axially away from the radial wall and the first end section, and an annular second end section extending radially inward from the axial wall of the intermediate section. The seal case further includes an insert of the first end section made of a first material. The first end section and the radial wall of the intermediate section include a second material joined to the insert. The first material of the insert may be selected to provide improved durability and/or to resist expansion and contraction of the first end section caused by changes in temperature.

A high-pressure tank comprises a liner, a strengthening layer including a first helical layer and a first hoop layer each including a carbon fiber, and a protective layer including a second helical layer and a second hoop layer each including a glass fiber, in this order. The high-pressure tank is provided with a stress-generating portion, a reinforcement layer includes a first area α overlapping the stress-generating portion in a stacking direction and a second area β that is an area except for the first area, and a one-round portion including a final crossing portion at an end of winding of the glass fiber constituting the second hoop layer overlaps the second area in the stacking direction.

A high-pressure tank comprises a liner, a strengthening layer including a first helical layer and a first hoop layer each including a carbon fiber, and a protective layer including a second helical layer and a second hoop layer each including a glass fiber, in this order. The high-pressure tank is provided with a stress-generating portion, a reinforcement layer includes a first area α overlapping the stress-generating portion in a stacking direction and a second area β that is an area except for the first area, and a one-round portion including a final crossing portion at an end of winding of the glass fiber constituting the second hoop layer overlaps the second area in the stacking direction.

The disclosure describes composite liners (such as acoustic panels, fan track liners, and/or ice impact panels or boxes for turbofan engines) and techniques for forming composite liners. In some examples, the composite liner includes at least one region comprising a reinforcement architecture comprising a matrix material, a plurality of relatively tough polymer-based reinforcement elements, and a plurality of second reinforcement elements. The plurality of relatively tough polymer-based reinforcement elements and the plurality of second reinforcement elements are embedded in the matrix material.

A method of manufacturing a fabric structure for use in manufacturing a composite aircraft blade. The method comprises: combining yarns including both reinforcing material filaments and a matrix material with yarns of reinforcing material filaments and/or yarns including at least one filament of matrix material; or by combining yarns of reinforcing material filaments with yarns including at least one filament of matrix material; or by combining yarns each comprising both reinforcing material filaments and matrix material. Combining may comprise weaving, knitting or braiding. The matrix material may be a thermoplastic.

A composite wheel assembly and method of fabricating the same is provided. The wheel assembly includes a composite wheel rim, a wheel center, and a plurality of attachment fasteners for attaching the wheel center to the wheel rim. The wheel rim includes a plurality of attachment inserts that are configured to selectively engage with respective attachment fasteners. Each attachment insert is encapsulated by a plurality of composite layers of the wheel rim or is otherwise secured to the wheel rim. The attachment inserts extend from and/or are positioned within a drop well region of the wheel rim. The method of fabricating the wheel assembly includes forming first and second preforms and positioning the same onto a mold assembly. The method further includes positioning the attachment inserts between the first and second preforms such that the attachment inserts are secured therebetween.

A method of forming set pin hole of an insulated carbine hook includes: providing a core material with a perforation and a recess; putting the core material in a mold cavity of a mold including a movable pin protruding from an inner surface of the mold cavity, which is at an opening of the perforation; filling insulated material between an outer surface of the core material and the inner surface, and in the perforation and recess; forming an insulated layer on the outer surface and in the perforation and recess to obtain an insulated intermediate having a notch at the opening; aiming a removal tool at the notch; removing the insulated material at the other opening of and in the perforation, and at an opening of and in the recess to form the set pin hole, which makes the manufacturing a main body of the insulated carbine hook easy.

Method for manufacturing a stiffened panel of composite materials and a stiffened panel, comprising: a skin (1), and stiffeners (3, 4),
wherein the manufacturing method comprises the following steps: providing a skin (1), making a plurality of through drill holes (6) on the skin (1) located in correspondence with areas where the placement of stiffeners (3, 4) is expected, introducing threaded bolts (5) in the through drill holes (6) such that the head (11) of the threaded bolt (5) remains housed in the skin (1), locating a threaded nut (10) on the free end of the threaded bolts (5), manufacturing the stiffeners (3, 4) such that the threaded bolts (5) and the threaded nut (10) remain embedded in the stiffeners (3, 4).