Abstract: This invention relates to the operation of gas turbine engines, and in particular to determining deterioration of components during operation. In a specific embodiment, the invention is concerned with determining the actions to be taken when a foreign body impact has been detected, for example on a fan blade. Accordingly, the invention provides a method to take one or more FOD detection apparatus, analyse the likely (probabilistic) outcome, and provide a system to determine subsequent action that assures safety whilst minimising operational disruption. This invention provides a method and apparatus to identify FOD or bird impact to gas turbine fan blades, assessing the damage that may have occurred whist still in flight and determining post impact actions, including replacement parts.

Abstract: An apparatus for manufacturing an article from powder material includes a canister, a sorter, a plurality of hoppers and at least one valve. The canister has a predetermined internal shape to define the shape of the powder metal article. The sorter sorts the powder material by the size of the powder particles, the shape of the powder particles and/or the flow characteristics of the powder particles. The hoppers contain powder material with different sizes of powder particles, different shapes of powder particles and/or powder particles with different flow characteristics. The hoppers are arranged to supply the sorted powder material to the canister. The at least one valve controls the proportions of the different powder materials supplied from the one or more of the different hoppers into the canister to control the packing density of the powder material in the canister at all positions in the canister.

Abstract: Conventional curable polymers tend to shrink upon curing whilst low shrinkage ultraviolet light curing polymers have a problem with respect to curing below surface areas of a component. By providing light transmitting elements and/or local ultraviolet light source precursors, greater depth of ultraviolet curing can be achieved and therefore enhanced acceptability with regard to component manufacture. The light transmitting elements may be formed by optic fibers or coatings to existing reinforcing fibers or through consideration of the refractive index of the cured and uncured polymer to create light transmission paths through the component. Ultraviolet light source precursors can be activated by heat or a “seed” light exposure or vibration to create localised ultraviolet curing of the polymer thereabout.

Abstract: The invention relates to a joint including a substrate, optionally a metal substrate, and a body of material joined to the substrate, the body of material typically having a composite portion. An outer surface of the substrate is provided with a fastening projection for fastening the substrate to body of material, wherein the fastening projection has a stem and a plurality of branches having dendritic geometry projecting into the material of the body.

Abstract: Tip rub in gas turbine engines is a well-known phenomenon, and may lead to increased tip clearances, with consequent detrimental effects on the engine's performance and blade flutter margins. Heavy or repeated rubbing may cause blade tip over temperature leading to cracking and fatigue failure. The invention provides a tip for a gas turbine engine rotor blade, which under contact with the casing surface interacts with the casing surface so as to reduce the contact force and thereby reduce the energy transferred to the blade. The tip may be designed to ablate under contact with the casing surface, or to cut or abrade the casing surface, or to crush or compress of deflect under contact with the casing surface. In a preferred embodiment, the tip comprises fibre-reinforced metallic foam material.

Abstract: International regulations for aerofoils within gas turbine engines require the safe containment of a released aerofoil. The blade fragments must be contained within an engine casing. Smaller fragments will generally be easier to contain within the casing and therefore reduce the weight of that casing. However introducing lines of weakness may result in cavities and holes which are subject to moisture ingress and problems associated therewith. By providing a root section which incorporates a core having shear surfaces, blades can be designed which in normal use are subject to compressive loads and remain operational, but when subject to impact loads or bending forces create tension forces which cause fragmentation along the shear surfaces after initial energy losses by slippage. By providing the shear surfaces in cores their location is encapsulated avoiding problems with moisture ingress.

Abstract: A fan assembly of a gas turbine engine, the fan assembly includes an array of radially extending blades defining gaps therebetween and an annulus filler located within at least one gap. The annulus filler includes at least two individual bodies arranged circumferentially adjacent one another with at least one adjacent a blade, one of the bodies includes a flexible wall arranged to centrifuge outwardly against the other body thereby urging both bodies against the blades and securing them during engine operation.

Abstract: A fan blade for a gas turbine engine has an aerofoil part and a root part. The root part includes a root former; the root former includes a zone of weakness, which reduces the ability of the root part to withstand an impact force. Thus, in an impact situation in which the fan blade has separated from the fan rotor and the fan blade has itself separated into fragments, the root part will fracture or buckle more easily than would be the case with conventional arrangements. This will lower the impact force of the root part upon the fan casing, thus permitting the fan casing to be designed to withstand lower impact forces. The fan casing can therefore be made lighter, and cheaper, than in conventional arrangements.

Abstract: A fan blade for a gas turbine engine has an aerofoil part and a root part. The root part includes a root former; the root former 18 includes a zone of weakness, which reduces the ability of the root part to withstand an impact force. Thus, in an impact situation in which the fan blade has separated from the fan rotor and the fan blade has itself separated into fragments, the root part will fracture or buckle more easily than would be the case with conventional arrangements. This will lower the impact force of the root part upon the fan casing, thus permitting the fan casing to be designed to withstand lower impact forces. The fan casing can therefore be made lighter, and cheaper, than in conventional arrangements.

Abstract: Blade assemblies are provided in a number of forms. These blade assemblies may have blades secured to disks (blisk), rings (bling) and drums (blum). The blades and/or the rotor elements formed by these rings, drums or disks can fragment and it is necessary to contain such fragments within a casing. Impact energy has a significant effect upon the necessary thickness of the casing to ensure containment. By providing blades as well as rotor elements which incorporate discontinuities which provide flexing under impact, energy is absorbed prior to further fragmentation upon impact engagement with a casing surface; flexing is about the discontinuity. In such circumstances casings may be thinner and therefore significant weight savings achieved with regard to aircraft incorporating gas turbine engines having blade assemblies with discontinuities.

Abstract: A fan blade for a gas turbine engine has an aerofoil part and a root part. The root part includes a root former; the root former 18 includes a zone of weakness, which reduces the ability of the root part to withstand an impact force. Thus, in an impact situation in which the fan blade has separated from the fan rotor and the fan blade has itself separated into fragments, the root part will fracture or buckle more easily than would be the case with conventional arrangements. This will lower the impact force of the root part upon the fan casing, thus permitting the fan casing to be designed to withstand lower impact forces. The fan casing can therefore be made lighter, and cheaper, than in conventional arrangements.

Abstract: International regulations for aerofoils within gas turbine engines require the safe containment of a released aerofoil. The blade fragments must be contained within an engine casing. Smaller fragments will generally be easier to contain within the casing and therefore reduce the weight of that casing. However introducing lines of weakness may result in cavities and holes which are subject to moisture ingress and problems associated therewith. By providing a root section which incorporates a core having shear surfaces, blades can be designed which in normal use are subject to compressive loads and remain operational, but when subject to impact loads or bending forces create tension forces which cause fragmentation along the shear surfaces after initial energy losses by slippage. By providing the shear surfaces in cores their location is encapsulated avoiding problems with moisture ingress.

Abstract: Blade assemblies are provided in a number of forms. These blade assemblies may have blades secured to disks (blisk), rings (bling) and drums (blum). The blades and/or the rotor elements formed by these rings, drums or disks can fragment and it is necessary to contain such fragments within a casing. Impact energy has a significant effect upon the necessary thickness of the casing to ensure containment. By providing blades as well as rotor elements which incorporate discontinuities which provide flexing under impact, energy is absorbed prior to further fragmentation upon impact engagement with a casing surface; flexing is about the discontinuity. In such circumstances casings may be thinner and therefore significant weight savings achieved with regard to aircraft incorporating gas turbine engines having blade assemblies with discontinuities.

Abstract: Conventional curable polymers tend to shrink upon curing whilst low shrinkage ultraviolet light curing polymers have a problem with respect to curing below surface areas of a component. By providing light transmitting elements and/or local ultraviolet light source precursors, greater depth of ultraviolet curing can be achieved and therefore enhanced acceptability with regard to component manufacture. The light transmitting elements may be formed by optic fibers or coatings to existing reinforcing fibers or through consideration of the refractive index of the cured and uncured polymer to create light transmission paths through the component. Ultraviolet light source precursors can be activated by heat or a “seed” light exposure or vibration to create localised ultraviolet curing of the polymer thereabout.

Abstract: A method and system for detecting an anomaly in a fluid system, comprising exposing a sample of the fluid system to a first, non-oscillating magnetic field, simultaneously exposing the sample to a second, oscillating magnetic field orthogonal to the first field, modulating one or both of the magnetic fields, and detecting and capturing a resulting NMR signal from the sample. An analysis of the captured signal, typically involving transformation of the signal into an NMR frequency domain spectrum, can be performed to look for specific changes in the signal indicative of the presence of a particular anomaly.

Abstract: A method and system for detecting an anomaly in a fluid system, comprising exposing a sample of the fluid system to a first, non-oscillating magnetic field, simultaneously exposing the sample to a second, oscillating magnetic field orthogonal to the first field, modulating one or both of the magnetic fields, and detecting and capturing a resulting NMR signal from the sample.