Abstract: An image generating device comprises a light source producing a light beam and a screen (5) traversed by the light beam and designed to modify the light beam so as to form an image. The screen (5) comprises a transparent element (150) traversed by the light beam and designed to evacuate the heat generated at the level of the screen (5). Said transparent element (150) is made of sintered transparent ceramic. Also described are a head-up display comprising such a device, and a method for manufacturing an image generating device.

Abstract: An inertial particle separator for an aircraft engine inlet, including inlet, intermediate and bypass ducts. The intermediate duct extends generally transversally from the inlet duct to the engine inlet, and communicates with the inlet duct adjacent its downstream end. The bypass duct extends downstream from the inlet duct and intermediate duct, and defines an outlet communicating with the environment of the engine. A wall of the intermediate duct intersects a wall of the inlet duct on an engine side of the wall of the inlet duct. The engine side of the wall of the inlet duct defines an engine-side inlet air flow line of the inertial particle separator. A wall of the bypass duct intersects the wall of the intermediate duct closer to a central axis of the engine than an extension of the engine-side inlet air flow line into the bypass duct.

Abstract: A method and system for operating an inlet door of an auxiliary power unit are provided. A control signal comprising at least one inlet door command is output. In response to the at least one inlet door command, at least one feedback signal is received and compared to the at least one inlet door command. If the at least one received feedback signal matches the at least one expected feedback signal, operation of the auxiliary power unit is allowed. Otherwise, operation of the auxiliary power unit is inhibited.

Abstract: An air intake for efficiently channeling a flow of ambient air toward an air inlet of a turboprop or turboshaft gas turbine engine is disclosed. The air intake comprises an intake inlet for receiving the flow of air, an intake duct for channelling the flow of air, and an intake outlet for discharging the flow of air toward the air inlet of the gas turbine engine. The intake duct may be oriented toward a flow direction of the air pushed aft by a propeller coupled to the gas turbine engine.

Abstract: A method and system for obtaining single-frequency operation of a laser system. A laser beam is emitted from a laser cavity, having an adjustable length, at a plurality of cavity lengths. At least a portion of the laser beam is received at a detector, which detects the presence of transverse and/or longitudinal modes in the laser beam, and generates a laser beam signal having a beat-note indicative thereof. The laser beam signal for each of the plurality of cavity lengths can be analyzed, and a cavity length of best mode purity, indicating single-frequency operation, can be selected. The laser beam system can emit a laser and have a laser beam splitter for directing at least a portion of the emitted laser beam to a laser beam detector for generating at least one laser beam signal therefrom, and an actuator for adjusting the length of the laser cavity.

Abstract: A method and system for operating an inlet door of an auxiliary power unit are provided. A control signal comprising at least one inlet door command is output. In response to the at least one inlet door command, at least one feedback signal is received and compared to the at least one inlet door command. If the at least one received feedback signal matches the at least one expected feedback signal, operation of the auxiliary power unit is allowed. Otherwise, operation of the auxiliary power unit is inhibited.

Abstract: An air intake for efficiently channeling a flow of ambient air toward an air inlet of a turboprop or turboshaft gas turbine engine is disclosed. The air intake comprises an intake inlet for receiving the flow of air, an intake duct for channelling the flow of air, and an intake outlet for discharging the flow of air toward the air inlet of the gas turbine engine. The air intake may comprise a scroll portion and a strutted portion configured to receive the flow of air from the intake duct and channel the flow of air toward the intake outlet. The strutted portion may comprise one or more vanes for interacting with the flow of air. The intake duct may be oriented toward a flow direction of the air pushed aft by a propeller coupled to the gas turbine engine.

Abstract: An inertial particle separator for an aircraft engine inlet, including inlet, intermediate and bypass ducts. The intermediate duct extends generally transversally from the inlet duct to the engine inlet, and communicates with the inlet duct adjacent its downstream end. The bypass duct extends downstream from the inlet duct and intermediate duct, and defines an outlet communicating with the environment of the engine. A wall of the intermediate duct intersects a wall of the inlet duct on an engine side of the wall of the inlet duct. The engine side of the wall of the inlet duct defines an engine-side inlet air flow line of the inertial particle separator. A wall of the bypass duct intersects the wall of the intermediate duct closer to a central axis of the engine than an extension of the engine-side inlet air flow line into the bypass duct.

Abstract: An air intake for efficiently channeling a flow of ambient air toward an air inlet of a turboprop or turboshaft gas turbine engine is disclosed. The air intake comprises an intake inlet for receiving the flow of air, an intake duct for channelling the flow of air, and an intake outlet for discharging the flow of air toward the air inlet of the gas turbine engine. The air intake may comprise a scroll portion and a strutted portion configured to receive the flow of air from the intake duct and channel the flow of air toward the intake outlet. The strutted portion may comprise one or more vanes for interacting with the flow of air. The intake duct may be oriented toward a flow direction of the air pushed aft by a propeller coupled to the gas turbine engine.

Abstract: An air intake for efficiently channeling a flow of ambient air toward an air inlet of a turboprop or turboshaft gas turbine engine is disclosed. The air intake comprises an intake inlet for receiving the flow of air, an intake duct for channelling the flow of air, and an intake outlet for discharging the flow of air toward the air inlet of the gas turbine engine. The intake duct may be oriented toward a flow direction of the air pushed aft by a propeller coupled to the gas turbine engine.

Abstract: An exhaust mixer for a gas turbine engine has a lobe cross-over offset. The proposed geometric feature leads to improved exhaust performance and potential weight reduction.

Abstract: A first and second engine are connected to a drive train for driving an aircraft accessory. A gearbox is connected to a primer mover propulsor and an actuator operatively associated with a selected engine is moveable between a position in which the selected engine drivingly engages the gearbox for driving the propulsor and a position in which the selected engine disengages from the gearbox. A position signal, a status signal, and a request signal respectively indicative of a present position of the actuator, a governing state and present speed of each engine, and a request for movement of the actuator from the present position to the other position are received. If the selected engine's speed differs from a predetermined threshold, a control signal is output for causing the engine's speed to be adjusted towards the threshold. A control signal indicating that movement of the actuator is permitted is then output.

Abstract: For increasing the power emitted by surface emitting lasers and for improving the spatial coherence of the laser beam, emitted in particular by disk lasers, microchip lasers and VCSELs having a relatively wide emitting area, the invention proposes to select a low order transverse cavity mode by means of a mirror structure (12) of high reflectivity, and of high angular selectivity. The mirror structure comprises a multilayer (14) receiving the optical beam (24) and a resonant grating mirror (16) following the multilayer and arranged for highly reflecting the optical beam in a narrow angular range at each side of a determined incidence angle.

Abstract: For increasing the power emitted by surface emitting lasers and for improving the spatial coherence of the laser beam, emitted in particular by disk lasers, microchip lasers and VCSELs having a relatively wide emitting area, the invention proposes to select a low order transverse cavity mode by means of a mirror structure (12) of high reflectivity, and of high angular selectivity. The mirror structure comprises a multilayer (14) receiving the optical beam (24) and a resonant grating mirror (16) following the multilayer and arranged for highly reflecting the optical beam in a narrow angular range at each side of a determined incidence angle.