Abstract: A temperature indicating device which comprises a plurality of panels in a fixed array. Some of the panels are adapted to undergo a reversible change in appearance at a given temperature whereas the remainder are adapted to undergo irreversible change in appearance at a given temperature. The device is useful in indicating the temperature which an object has achieved as well as its actual temperature.

Abstract: A method of manufacturing a bladed disc from a fiber reinforced composite material which comprises injecting a mixture of short fibers and a matrix material into a dividable die so configured as to define the form of a disc having integral radially extending aerofoil blades. The mixture is injected into the die at such a location that the short fibers within the aerofoil-defining portions of the die are radially aligned. The die contains two support rings which are coaxially disposed within the bladed disc after injection molding so as to provide radial support for the aerofoil blades of the thus formed bladed disc. The method may be modified to provide the bladed disc with an integral shroud.

Abstract: A gas turbine engine disc having integral, radially extending aerofoil blades and an integral shroud interconnecting the radially outer extents of the blades is described. In the manufacture thereof continuous fibres are wound around an annular array of inserts provided in a dividable disc. The inserts define the spaces between adjacent blades on the disc. A mixture of chopped carbon fibre and an epoxy resin matrix material is then injected into the central portion of the die interior. Any part of the wound fibres which has not been impregnated by the chopped fibre/resin matrix material is subsequently impregnated by a matrix material whereupon the die is opened to release the thus produced bladed disc.

Abstract: A compressor rotor assembly comprises a shaft and at least one disc having integral radially extending aerofoil blades which disc is integral with the shaft. The assembly comprises a matrix material in which a plurality of short reinforcing fibres are so disposed that the majority thereof within the shaft are generally axially aligned while the majority thereof within the aerofoil blades are generally radially aligned. At least one filament wound support ring provides radial support for the aerofoil blades.

Abstract: A hollow aerofoil cross-section aircraft propeller blade is provided with a tow of KEVLAR fibres internally thereof. The fibres which are anchored to the blade root and tip portions are arranged to be passive under all normal operating conditions of the blade. However in the event of a structural failure of the blade between its root and tip portions the fibres serve to contain the blade tip together with any portion of the blade attached thereto. The invention is additionally applicable to prop-fan and fan blades for gas turbine engines.

Abstract: Two seal elements are respectively mounted on generally coaxial relatively rotatable members so that each seal element is capable of relative radial movment with respect to its associated member. One of the seal elements is mounted on its associated member in such a manner that they remain coaxial. The seal elements have confronting radially spaced apart surfaces which are so configured that together they define a hydrodynamic gas bearing. The arrangement is such that upon the relative rotation of the members said seal element which is mounted so as to remain coaxial with its associated member hydrodynamically supports the other seal element so that they remain coaxial.

Abstract: A seal arrangement suitable for sealing between two coaxially mounted, axially restrained, radially spaced apart and relatively rotatable members comprises two concentric, ring-shaped seal elements having adjacent sealing faces. The seal elements are mounted on the respective members by a spline and groove arrangement which permits radial growth or shrinkage of the relatively rotatable members due to their thermal expansion or contraction without such growth or shrinkage being transferred to the seal elements. The arrangement insures that the gap between the sealing faces of the seal elements remains substantially constant during thermal variations.