Abstract: A control system includes an actuator, a locking/unlock device, a central control valve, first and second control valves, and a spool control valve. The actuator is arranged so as to move a door of a thrust reverser between direct jet and reverse jet positions. The locking/unlocking device unlockable under load allowing locking and/or unlocking of the door. The locking/unlocking device is movable between a closure position in which it holds the door in the direct jet position and an opening position in which the door is released. The first and second control valves each fed by the central control valve. The spool control valve fed at least by the first and second control valves. The spool control valve is configured so that a pressure difference between two inlets of the first and second control valves provides a displacement of the spool control valve between first and second stable positions.

Abstract: An air intake includes a substantially cylindrical inner wall, a substantially cylindrical outer wall, a front lip connecting the inner wall and the outer wall, a front mounting flange, and a support structure. The front mounting flange is configured to cooperate with a rear flange of a wall of an aircraft engine. The support structure is configured to be secured to the wall of the aircraft engine at a location longitudinally downstream of the mounting flange. The outer wall includes a downstream end configured to be positioned in a junction area flush with a front end of a fan external cowl. A portion of the outer wall being configured to bear at least against the support structure. The support structure is configured to be secured to the wall of the aircraft engine so that a load path passes directly from the outer wall towards the fan casing.

Abstract: A nacelle rear assembly of a nacelle of a turbojet engine of an aircraft extends along a longitudinal central axis (A) and includes a sliding cascade thrust reverser. The cascade thrust reverser includes at least one sliding cowl, a deflection cascade including a plurality of rows of vanes that each extend around the longitudinal central axis (A) and that are longitudinally arranged from a first front row of vanes up to a last rear row of vanes, each row of vanes including at least one deflection vane for deflecting the airflow toward the outside of the rear assembly of the nacelle, the deflection cascade being movably integral with the sliding cowl, wherein the deflection cascade includes at least one additional neutral row of vanes that is interposed between the last row of vanes and the sliding cowl and that includes at least one neutral vane.

Abstract: A closing system that includes a closing actuator for doors of a thrust reverser, two sliding members, and a detection device. The closing actuator includes two first connecting rods. Each first connecting rod is configured to be connected to a first lateral edge of each door. The closing actuator is arranged to move each door at least towards the direct jet position. Each sliding member carries a second connecting rod configured to be connected to a second lateral edge of each door. The second connecting rods are arranged to be driven by the doors when the closing actuator moves the doors towards the direct jet position so as to displace the two sliding members. The detection device detects a defect of one of the first and second connecting rods. The detection device is configured to detect the relative position of the two sliding members in the direct jet position.

Abstract: A turbojet engine nacelle having a cascade-type thrust reverser includes a movable frame surrounding a cold air flow path, guided axially by longitudinal rails fixed to an intermediate casing surrounding the cold air flow path and supporting cascades of thrust-reversal guide vanes and mobile rear cowls. The nacelle has a passage of ancillaries opening radially towards the outside of the movable frame, in a zone with no bearing structure passing radially across the cold air flow path. The movable frame is cut in an axial plane at the passage for the passage of ancillaries, and each edge of the cut of the movable frame is connected to the intermediate casing by a slide rail fitted on a longitudinal rail arranged each on one side of this passage.

Abstract: A thrust reverser for an aircraft propulsion assembly includes a movable structure provided with external covers connected to hinges through a pivot connection allowing the external covers to rotate between a closed position and a maintenance position. The hinges are connected to secondary rails rigidly attached to an engine pylon through a sliding connection allowing the external covers to move in translation between a direct thrust position and a reverse thrust position. The hinges and the secondary rails are independent of beams to which the parts of the movable structure other than the external covers are connected. A method for maintaining an aircraft propulsion unit is also disclosed. The method includes positioning of the external covers in maintenance position followed by a placement of the beams and of the parts of the movable structure other than the external covers.

Abstract: A nacelle for a bypass turbojet engine includes a cascade thrust reverser provided with reversal cascades arranged around an annular stream of fresh air, beneath front cowls. The cascades move backward with movable rear cowls, opening side passages in the annular stream, which receive the cascades for directing the fresh air flow forward, the bypass turbojet engine. The bypass turbojet engine includes fixing points, and the nacelle includes outer hatches closing openings of the front cowls, which are arranged radially outside the fixing points for access thereto, each hatch opening including a contour with edges of two front cowls.

Abstract: An acoustic attenuation panel includes a cellular structure including a plurality of acoustic cells separated from one another by peripheral partitions, a perforated acoustic structure, the perforated acoustic structure and the cellular structure being formed in one piece in a first material, and a porous acoustic layer formed of a second material and fastened to a surface of the perforated acoustic structure by entangling the first material and the second material.

Abstract: A closing system that includes a closing actuator for doors of a thrust reverser, two sliding members, and a detection device. The closing actuator includes two first connecting rods. Each first connecting rod is configured to be connected to a first lateral edge of each door. The closing actuator is arranged to move each door at least towards the direct jet position. Each sliding member carries a second connecting rod configured to be connected to a second lateral edge of each door. The second connecting rods are arranged to be driven by the doors when the closing actuator moves the doors towards the direct jet position so as to displace the two sliding members. The detection device detects a defect of one of the first and second connecting rods. The detection device is configured to detect the relative position of the two sliding members in the direct jet position.

Abstract: A thrust reverser includes two thrust reverser elements movable between a retracted position in which the thrust reverser is inactive and a deployed position in which the thrust reverser is active, a cylinder for deploying the thrust reverser elements, and a single-acting cylinder for retracting the thrust reverser elements.

Abstract: An aircraft propulsion unit including a nacelle and a turbojet engine. The aircraft propulsion unit includes an external envelope, at least one fan casing, at least one actuator, and at least one support structure. The external envelope includes fan cowls. The fan casing cooperates with the fan cowls to define an interior space configured to house a thrust reverser configured to be displaced between a first position and a second position. The actuator configured to move the thrust reverser between the first position and the second position The support structure connects the fan cowls and the fan. The support structure includes at least one aperture configured to allow passage of part of the actuator.

Abstract: An air intake of a turbojet engine nacelle includes an annular structure including an outer fairing defining an aerodynamic outer surface and an inner fairing defining an aerodynamic inner surface. The outer and inner fairings are connected upstream by an air intake lip forming a leading edge. The inner fairing includes an outer skin fixed to the air intake lip by an upstream fixation flange, and the outer skin is configured to be fixed to an outer fan casing by a downstream fixation flange. The air intake includes at least one independent acoustic panel attached to the outer skin and which includes a perforated acoustic skin and a cellular core.

Abstract: An air intake includes a substantially cylindrical inner wall, a substantially cylindrical outer wall, a front lip connecting the inner wall and the outer wall, a front mounting flange, and a support structure. The front mounting flange is configured to cooperate with a rear flange of a wall of an aircraft engine. The support structure is configured to be secured to the wall of the aircraft engine at a location longitudinally downstream of the mounting flange. The outer wall includes a downstream end configured to be positioned in a junction area flush with a front end of a fan external cowl. A portion of the outer wall being configured to bear at least against the support structure. The support structure is configured to be secured to the wall of the aircraft engine so that a load path passes directly from the outer wall towards the fan casing.

Abstract: A control system includes an actuator, a locking/unlock device, a central control valve, first and second control valves, and a spool control valve. The actuator is arranged so as to move a door of a thrust reverser between direct jet and reverse jet positions. The locking/unlocking device unlockable under load allowing locking and/or unlocking of the door. The locking/unlocking device is movable between a closure position in which it holds the door in the direct jet position and an opening position in which the door is released. The first and second control valves each fed by the central control valve. The spool control valve fed at least by the first and second control valves. The spool control valve is configured so that a pressure difference between two inlets of the first and second control valves provides a displacement of the spool control valve between first and second stable positions.

Abstract: An aircraft propulsion assembly with an engine provided with a cascade-type thrust reverser includes cascades of mobile deflection vanes connected to cascade rails with a slideway connection that allows the cascades of vanes a translational movement between a cruising-flight position and a reverse-thrust position. The thrust reverser allows the cascade rails to be positioned in a forward position, in which the engine, the cascade rails and the deflection vanes can be removed from the propulsion assembly without the cascade rails colliding with the mobile cowl of the reverser. Dismantling and assembly or reassembly methods allow maintenance operations to be carried out on the engine thus dismantled.

Abstract: A nacelle for a turbojet includes a thrust reverser having cascades, movable cowls adjacent to the cascades in a closed position, linkage systems for connecting the cowls and the cascades, and tilting closure flaps. Each linkage system is arranged radially outside the cascades, and includes, in a tangential plane, a lever, connecting rods, and pivots allowing a movement substantially in this plane. The pivots include a fixed pivot connected to a fixed element of the nacelle, a pivot connected to the cascades and a pivot connected to the cowls. The lever, termed first lever, includes two arms forming a “V,” and two connecting rods are fixed to the end of an arm by a pivot.

Abstract: A thrust reverser for an aircraft propulsion assembly includes a movable structure provided with external covers connected to hinges through a pivot connection allowing the external covers to rotate between a closed position and a maintenance position. The hinges are connected to secondary rails rigidly attached to an engine pylon through a sliding connection allowing the external covers to move in translation between a direct thrust position and a reverse thrust position. The hinges and the secondary rails are independent of beams to which the parts of the movable structure other than the external covers are connected. A method for maintaining an aircraft propulsion unit is also disclosed. The method includes positioning of the external covers in maintenance position followed by a placement of the beams and of the parts of the movable structure other than the external covers.

Abstract: A turbojet engine nacelle having a cascade-type thrust reverser includes a movable frame surrounding a cold air flow path, guided axially by longitudinal rails fixed to an intermediate casing surrounding the cold air flow path and supporting cascades of thrust-reversal guide vanes and mobile rear cowls. The nacelle has a passage of ancillaries opening radially towards the outside of the movable frame, in a zone with no bearing structure passing radially across the cold air flow path. The movable frame is cut in an axial plane at the passage for the passage of ancillaries, and each edge of the cut of the movable frame is connected to the intermediate casing by a slide rail fitted on a longitudinal rail arranged each on one side of this passage.

Abstract: A nacelle rear assembly of a nacelle of a turbojet engine of an aircraft extends along a longitudinal central axis (A) and includes a sliding cascade thrust reverser. The cascade thrust reverser includes at least one sliding cowl, a deflection cascade including a plurality of rows of vanes that each extend around the longitudinal central axis (A) and that are longitudinally arranged from a first front row of vanes up to a last rear row of vanes, each row of vanes including at least one deflection vane for deflecting the airflow toward the outside of the rear assembly of the nacelle, the deflection cascade being movably integral with the sliding cowl, wherein the deflection cascade includes at least one additional neutral row of vanes that is interposed between the last row of vanes and the sliding cowl and that includes at least one neutral vane.

Abstract: A nacelle for a bypass turbojet engine includes a cascade thrust reverser provided with reversal cascades arranged around an annular stream of fresh air, beneath front cowls. The cascades move backward with movable rear cowls, opening side passages in the annular stream, which receive the cascades for directing the fresh air flow forward, the bypass turbojet engine. The bypass turbojet engine includes fixing points, and the nacelle includes outer hatches closing openings of the front cowls, which are arranged radially outside the fixing points for access thereto, each hatch opening including a contour with edges of two front cowls.