Abstract: A system and a method of testing a specimen. The system includes an endcap, a plurality of bars, a plurality of strain gauges, and a gas gun. The endcap includes a first surface and a second surface opposite to the first surface. The first surface is curved. Each bar is disposed in contact with the second surface of the endcap and extends along a longitudinal axis. Each strain gauge is disposed on a surface of a corresponding bar from the plurality of bars. At least one strain gauge is disposed on the surface of each bar. The gas gun is configured to fire a specimen towards the first surface of the endcap such that the specimen impacts the first surface at an oblique angle relative to the longitudinal axis.

Abstract: A system for measuring loading on a test specimen. The system includes the test specimen arranged between a first loading bar and a second loading bar. The system further includes a first loading unit and a second loading unit configured to apply a first load and a second load to the first and second loading bars, respectively. The system further includes a first clamp and a second clamp configured to hold the first and second loading bars against the first and second loads, respectively. The system further includes a clamp actuating unit configured to selectively release at least the first clamp. The clamp actuating unit further includes a controller configured to electrically actuate at least one first electromechanical transducer from a retained state to a released state to release the first clamp, such that the first loading bar applies a first loading wave to the test specimen.

Abstract: A fan blade containment system is arranged to surround a fan including a plurality of fan blades in a gas turbine engine for an aircraft. The fan blade containment system includes a fan case arranged to surround the fan; a debris retainer, such as a front hook, mounted on the fan case and arranged to prevent forward debris release should all or part of a fan blade become detached from the fan; and a front panel mounted on the fan case adjacent to and rearward of the front hook, and arranged to move or break when struck by a detached fan blade or fan blade part so as to allow the detached fan blade or fan blade part to engage the front hook.

Abstract: A fan blade containment system is arranged to surround a fan including a plurality of fan blades in a gas turbine engine for an aircraft. The fan blade containment system includes a composite fan case arranged to surround the fan; and a metallic insert mounted on the composite fan case and including a metallic hook arranged to prevent forward debris release should all or part of a fan blade become detached from the fan.

Abstract: A fan blade containment system is arranged to surround a fan including a plurality of fan blades in a gas turbine engine for an aircraft. The fan blade containment system includes a fan case arranged to surround the fan and two debris retainers. The first debris retainer extends inwardly from the fan case and is arranged to prevent forward debris release should all or part of a fan blade become detached from the fan, the first debris retainer being located near and forward of the fan. The second debris retainer extends inwardly from the fan case and is arranged to prevent forward debris release should all or part of a fan blade become detached from the fan, the second debris retainer being located forward of the first debris retainer.

Abstract: A fan blade containment system is arranged to surround a fan including a plurality of fan blades in a gas turbine engine for an aircraft. The fan blade containment system includes a composite fan case arranged to surround the fan; and a metallic insert mounted on the composite fan case and including a metallic hook arranged to prevent forward debris release should all or part of a fan blade become detached from the fan.

Abstract: A fan blade containment system is arranged to surround a fan including a plurality of fan blades in a gas turbine engine for an aircraft. The fan blade containment system includes a fan case arranged to surround the fan; a debris retainer, such as a front hook, mounted on the fan case and arranged to prevent forward debris release should all or part of a fan blade become detached from the fan; and a front panel mounted on the fan case adjacent to and rearward of the front hook, and arranged to move or break when struck by a detached fan blade or fan blade part so as to allow the detached fan blade or fan blade part to engage the front hook.

Abstract: A fan casing arrangement for a gas turbine engine, the arrangement comprising an annular casing member and a fan track liner provided radially inward of the casing member and connected thereto. A forward portion of a gas washed surface of the fan track liner is curved so as to define a concave portion of the gas washed surface (e.g. curved such that the radial position of said forward portion of the gas washed surface varies in an axial direction).

Abstract: A joint assembly for securing flanges of two casings comprising a plurality of bolts, a plurality of collars and a plurality of nuts. Each bolt extends through an aperture in the first flange and an aperture in the second flange, each collar being arranged around a shank of a respective bolt and each nut being secured on a respective one of the bolts. Each collar being arranged between one of the flanges and a nut or a head of a bolt. Each collar comprises a first member and a second member, the second member being arranged at a first end of the first member. The second member being substantially U-shaped in cross-section, the second member having first and second radially inner ends and a radially outer mid portion and an axial space is defined between the first radially inner end and the second radially inner end of the second member.

Abstract: A turbomachine casing assembly including: a first casing element arrangeable adjacent to one or more rotating aerofoil structures of a turbomachine; a second casing element provided at a radially outer position with respect to the first casing element; and an infill member disposed between the first and second casing elements, wherein an end of the infill member is set back from an end of the first casing element such that a void is provided between the first and second casing elements.

Abstract: A gas turbine engine fan casing duct wall comprises an intake section and a containment casing, provided respectively with flanges. An acoustic flutter damper is secured between the flanges. The acoustic flutter damper has a skin accommodating an internal structure that dampens fan blade flutter. The skin is secured to the flanges at separate locations. In normal operation of the engine, the internal structure is sufficiently robust to support loads transmitted through the acoustic flutter damper between the intake section and the containment casing. If a blade or blade fragment detaches, the resulting deflection wave in the containment case ruptures the internal structure, and the load path between the intake section and the containment casing passes along the skin, which consequently maintains the connection between the intake duct and the containment casing, while permitting substantial radial deflection of the containment casing relative to the intake section.

Abstract: A fan casing for a gas turbine engine has a fan track radially outward of the fan blades, and the fan track has sufficient strength and stiffness that, if a blade is released, it is broken up and deflected by the fan track rather than passing through to a containment system as in known arrangements. Optionally, a weakened region in the fan track may be provided, so that the leading edge portion of the blade will penetrate the fan track and be contained within the fan casing. This is particularly suitable for fan blades in which the stiffness and compressive strength are significantly higher in the leading edge region than in the remainder of the blade; for example, hollow metal fan blades or composite fan blades having a metal leading edge cap.

Abstract: The fragmentation of a bird or similar soft body, following its impact on an angled target plate, is modeled by representing the body as a combination of fragments and slurry, their relative proportions depending on the severity and angle of impact. The method is particularly suitable for modeling the behavior of a bird striking an obscuring intake of a gas turbine engine.

Abstract: A turbomachine casing assembly including: a first casing element arrangeable adjacent to one or more rotating aerofoil structures of a turbomachine; a second casing element provided at a radially outer position with respect to the first casing element; and an infill member disposed between the first and second casing elements, wherein an end of the infill member is set back from an end of the first casing element such that a void is provided between the first and second casing elements.

Abstract: A joint assembly for securing flanges of two casings comprising a plurality of bolts, a plurality of collars and a plurality of nuts. Each bolt extends through an aperture in the first flange and an aperture in the second flange, each collar being arranged around a shank of a respective bolt and each nut being secured on a respective one of the bolts. Each collar being arranged between one of the flanges and a nut or a head of a bolt. Each collar comprises a first member and a second member, the second member being arranged at a first end of the first member. The second member being substantially U-shaped in cross-section, the second member having first and second radially inner ends and a radially outer mid portion and an axial space is defined between the first radially inner end and the second radially inner end of the second member.

Abstract: A fan casing for a gas turbine engine has a fan track liner extending only over an upstream part of the fan blades, and the local stiffness and internal shape of the casing are arranged to promote the break-up of a released fan blade while permitting the leading edge region of the blade to pass through the fan track liner and be contained by the fan casing. This arrangement is particularly suitable for fan blades in which the stiffness and compressive strength are significantly higher in the leading edge region than in the remainder of the blade; for example, hollow metal fan blades or composite fan blades having a metal leading edge cap.

Abstract: The fragmentation of a bird or similar soft body, following its impact on an angled target plate, is modelled by representing the body as a combination of fragments and slurry, their relative proportions depending on the severity and angle of impact. The method is particularly suitable for modelling the behaviour of a bird striking an obscuring intake of a gas turbine engine.

Abstract: A gas turbine engine fan casing duct wall comprises an intake section and a containment casing, provided respectively with flanges. An acoustic flutter damper is secured between the flanges. The acoustic flutter damper has a skin accommodating an internal structure that dampens fan blade flutter. The skin is secured to the flanges at separate locations. In normal operation of the engine, the internal structure is sufficiently robust to support loads transmitted through the acoustic flutter damper between the intake section and the containment casing. If a blade or blade fragment detaches, the resulting deflection wave in the containment case ruptures the internal structure, and the load path between the intake section and the containment casing passes along the skin, which consequently maintains the connection between the intake duct and the containment casing, while permitting substantial radial deflection of the containment casing relative to the intake section.

Abstract: An artificial bird projectile is provided for simulating bird strike events. The projectile has a solid foam phase and a gel or liquid phase. The gel or liquid phase is supported by the foam phase. The projectile may be suitable for simulating bird strike events on aero gas turbine engines.

Abstract: A fan casing for a gas turbine engine has a fan track radially outward of the fan blades, and the fan track has sufficient strength and stiffness that, if a blade is released, it is broken up and deflected by the fan track rather than passing through to a containment system as in known arrangements. Optionally, a weakened region in the fan track may be provided, so that the leading edge portion of the blade will penetrate the fan track and be contained within the fan casing. This is particularly suitable for fan blades in which the stiffness and compressive strength are significantly higher in the leading edge region than in the remainder of the blade; for example, hollow metal fan blades or composite fan blades having a metal leading edge cap.