Abstract: An arrangement for venting a destructive internal pressure generated by an explosion within an enclosure, such as aircraft fuselage. The arrangement includes a pressure venting device for venting an exterior boundary, fuselage skin, of the enclosure; and an explosion sensitive sensor located within the enclosure. In response to an explosion within the enclosure, the sensor will send a signal to the pressure venting device. The pressure venting device creates a pressure relieving vent in the exterior boundary in advance of build up of destructive internal pressure within the enclosure.

Abstract: A flow diverter arrangement for an aircraft comprises a first duct 17 for receiving propulsion fluid from the powerplant 11 and delivering it to a first location 18, a second duct 19 merging with the first duct 17 at a communication aperture 23 and adapted to deliver propulsion fluid to a second location, a flap member 24 pivotted for movement between a first position in which it closes the communication aperture 23 and a second position in which it closes the first duct, and a diverter device 31 for diverting propulsion fluid into the second duct when the flap member is in its second position.

Abstract: A secondary securing member is provided (19,28,29,30) for securing a first component (11) to a second component (13) when primary securing member (17) is inadvertently removed. The first component (11) includes an outwardly extending spigot (12) slidably engaging the secondary securing member (19, 28,29,30). The second component (13) is assembled and secured by a primary securing member means (17). Thus if in use, the primary securing member (17) is inadvertently removed, the secondary securing member (19, 28, 29, 30) insures limited axial displacement but no separation of the second component (13) from the first component (11).

Abstract: A microwave/millimetric receiver of the kind in which a dielectric lens focusses incoming radiation on to an integrated antenna/mixer supported by a dielectric substrate. In one embodiment the antenna/mixer comprises a slot antenna and diode means coupled thereto for mixing the received signal with a local oscillator signal to form an IF signal. The local oscillator signal may be irradiated on to the antenna/mixer to be picked up by a crossed slot antenna or the local oscillator signal may be directly injected into the antenna/mixer circuit say via a microstrip line. In an alternative embodiment, the slot antenna is replaced by a dipole and a local oscillator signal is directly injected into the antenna/mixer via a coplanar line.

Abstract: An optical arrangement for a helmet-mounted display for providing binocular presentation to a pilot from a single display source or for superimposing the images from two display sources on his helmet-mounted display. In one embodiment a single display source 1 provides an image which is alternately directed between left and right eyes of the pilot by means of one scanning mirror 4 and two fixed mirrors 5a and 5b. An iris 3 opens and closes in synchronism with the movement of the scanning mirror 4 in order to prevent image distortion. Because only one display source is required, the weight of the arrangement is kept to a minimum. In another embodiment, using similar core elements the images from two display sources are alternately projected on to the pilot's visor by means of similar fixed mirrors 5a and 5b and a scanning mirror 4, but using two iris' 3+ and 3" synchronised to the mirror movements one in each optical path from display source 1' (or 1") to fixed mirror 5a (or 5b).

Abstract: Cable handling and preparation apparatus comprising a cable source (12), cable stripping and crimping means (14), length determining means, robotic control means (13), cable guidance (43) and marking (11) means and cable conveying means (16). The arrangement is such that at least one cable or possibly more can be selectively drawn from a source comprising several powered cable reels (18) holding cables of different size by the robotic control means (13), subjected to processing by the stripping and crimping means (14) and subjected to marking, preferably laser marking, along its length, the prepared cable simultaneously and progressively being conveyed from the apparatus by the conveying means (16).

Abstract: A ball-screw includes a shaft 1 having two separate helical grooves 3,4 of the same pitch and spaced by half that pitch. The nut 2 includes two corresponding grooves and return bores 5 to define two endless recirculating paths for balls disposed between the nut and shaft. This arrangement permits, for a given groove pitch, the minimum length of the nut to be reduced.

Abstract: Dither applied to ring laser gyroscopes in order to counteract lock-in results in an unwanted signal that appears in the gyroscopes output. The invention is a way of reducing the unwanted signal due to dither. The proposed solution comprises decoding the gyroscope output signal into respective signals which represent clockwise and counter-clockwise motion, delaying a portion of each of these signals, and combining the delayed and non-delayed signals to derive an output representative of rotation of the gyroscope--the dither having a reduced effect on the output.

Abstract: An aircraft canopy ejection system includes a releasable coupling 22 in the load path between an opening/closing jack 19 and the canopy. The coupling 22 is released immediately before emergency jettison of the canopy.

Abstract: A vibrating planar ring or hoop-like structure is disclosed. The structure is suspended in space by a suitable support mount for detecting turning rate, linear acceleration and angular acceleration. Turning rate is sensed by detecting vibrations coupled by Coriolis forces, whereas linear acceleration and angular acceleration are sensed by lateral, vertical and rocking movement of the entire ring or hoop-like structure within its mount.

Abstract: The apparatus includes a solid state, two-dimensional, array (4) of elements or pixels fixedly attachable to the spacecraft or satellite (2) so that the array boresight (5) is aligned with the nominal Celestial Body pointing axis of the spacecraft or satellite (2). The elements or pixels are sensitive to illumination in the visible to near infra-red wavelength range, sense an image of Celestial Body (3) falling thereon and indicate the relative intensity of illumination falling on each element or pixel from the image. Optical means focus the image of Earth onto the array (4) and means for digitally sampling and processing the relative intensity of illumination information indicated by the array (4) operate to produce coordinates of the center (7) of the Celestial Body image on the array (4) whose displacement in two orthogonal axes from the center of the field of view of the array (4) provides an indication of the roll and/or pitch attitude error of the spacecraft or satellite (2).

Abstract: In conventional track-can manufacture they are formed from symmetrical halves made (for example, by drop hammering) split along the longitudinal axis of the finished component. The conventional welding process required to complete the track-cans is then complicated due to the arcuate configuration of these components.According to the present invention track-cans are manufactured from a plurality of substantially tubular sections, for example a cap-end (39), a body portion (43) and a flange end (40). The components are made by deep drawing from a blank cut of suitable material. The components are welded together at their interface regions to form the track-can. The tubular construction of the components enables the process of peripheral welding which in turn is comparatively simple, and particularly amenable to robotic welding. The prior art welding process was considerably more complicated due to the arcuate configuration of track-cans.

Abstract: This invention relates to a single axis solid state attitude sensor in which, the spatial orientation of a resonant rode on a resonant body is maintained in alignment with the inertial angle K8 of the resonant body.

Abstract: A method of constructing a carbon fiber composite wing in which upper and lower skins are bonded to a pre-assembled rib 15 and spar 16 framework, thus obviating the need for metal fasteners and hence cutting down assembly time. In one embodiment a novel cleat 17 of cruciform cross-section replaces the four cleats conventionally used for bolting the ribs 15 and spars 16 together. Holes 22 drilled in either end of the cleats serve as jig location points during framework assembly and anti-peel fastener holes after the skins have been bonded.

Abstract: A method of progressively molding and curing/homogenising a composite material component assembly including a skin panel and a series of spaced structurally reinforcing members therefor. The method includes the steps of placing a composite material layer (18) on support (13), clamping same to the support by a mold including first and second tools (14/16), the second tool being separated from the first tool by a pre-determined amount, slidably moving the second tool (16) towards the first tool (14) to cause the material to fold in an upwards direction until clamped between datum faces (15, 17) of the tools to define the structural member, heating the support (13) and tools (14, 16) to cure/homogenise the skin panel and structural members, then slidably moving the component along the support (13) a pre-determined amount to draw a further quantity of composite material layer (18) from a source and repositioning the tools (14, 16) for further processing of the material.

Abstract: A method and apparatus for transmitting data over a power line (2) and having particular application for flight control networks. The method enables bi-directional transmission of data over either DC or AC power lines. Transformers (T.sub.3, T.sub.4) used for coupling data onto and from the power lines (2) comprise three windings (L.sub.1, L.sub.2 and L.sub.3) and a ferrite core. Saturation of the core is avoided by arranging for the load current to flow in opposite senses through two (L.sub.1 and L.sub.2) of the windings. By choosing the number of turns of the two windings to be equal, complete cancellation of DC flux inside the core is possible.

Abstract: An assembly for hinging a canopy to a fuselage includes a hinge with a floating hinge axis which accommodates differential thermal expansion of the canopy and the fuselage.

Abstract: A laser markable white pigment composition includes a first pigment which is markable by ultraviolet laser, a second pigment, which is nonabsorbing in the ultraviolet region of the optical spectrum and which has a white appearance in the visible region of the optical spectrum, with the ratio of the amount of first pigment to amount of second pigment being in the range of from 4:1 to 1:10, so that the second pigment is present in an amount sufficient to increase the optical density, that is the whitening effect, of the composition, without adversely affecting the laser markability of the composition, and a carrier which is at least one fluoropolymer transparent in the ultraviolet region of the optical spectrum.

Abstract: A battery of dispersed missile launch stations (1-4) are linked to a central communications station (5) which assigns different targets to respective launch stations. The communications station ensures that only one launch station engages each target.

Abstract: An arrangement and method for damping induced fundamental vibrations in an aircraft high lift device (3) are provided. The arrangement includes a wing (2), a high lift device (3) mounted upon and movable along a pre-determined path with respect to the wing between a stowed cruise position and an extended high lift position, a track beam (8) interconnecting the wing and the high lift device (3), and a damping device (15) interconnecting the track beam and said wing and the track beam (8) pivotally connected to the wing (2) and including a trackway (20) for sliding interconnection with the high-lift device (3) such that while the high lift device (15) operates within acceptable vibrational tolerances the damping device is isolated but induced fundamental vibrations will cause angular displacement of the track beam (8) inducing a reactive force in the the damping device (15) to substantially nullify the fundamental vibrations.