Abstract: The invention relates to an electric thruster for a spacecraft. According to the invention, the thruster (II) comprises a jet generating portion (G1) and a jet accelerating portion (A2), pivotably connected (H1) such that the jet accelerating portion (A2) can rotate in relation to the jet generating portion (G1).

Abstract: Disclosed are a method and device for supplying a combustion chamber of a space propulsion engine with cryogenic liquid fuel and oxidizer propellants. The propellants are mixed at constant pressure to produce a propellant mixture, with the propellants being mixed at a location upstream of an orifice of a propellant injector. The propellant mixture is fed to an enclosure of the propellant injector, and from the propellant injector enclosure, the propellant mixture is injected into the combustion chamber. The flow rate of the propellant mixture from the propellant injector enclosure into the combustion chamber is varied by adjustment of the propellant injector, with the injection of the propellant mixture from the propellant injector enclosure into the combustion chamber being at constant pressure.

Abstract: A telecommunications system for intermittent data transfer from and to at least one user located substantially on the surface of a celestial body. The system comprises at least one surface transmitter/receiver terminal associated with each user, one or more signal repeater means for the signals transmitted and/or received from the surface terminals. Each moving repeater means has at least one antenna oriented toward the surface of the celestial body, and adapted to allow communications from and to surface terminals. Each antenna produces a transmission/reception beam, the track of which on the surface of the celestial body forms the ground track, the progressive sweeping of the surface by this ground track forming a strip called a swath.

Abstract: An expansion tube of a detonating pyrotechnic rupture piece is open next to pre-established rupture zones and, inside said open expansion tube there is disposed a sealed bladder which contains a pyrotechnic fuse.

Abstract: The present disclosure relates to a monitoring system which comprises at least one monitoring satellite placed in orbit at a lower altitude than that of the satellites of the satellite constellation so as to be capable of receiving the positioning signals emitted towards the Earth by said satellites, and which comprises a processing unit intended for verifying the integrity of said received positioning signals, using position information that is separate from said signals for this purpose.

Abstract: The invention provides a method for making a composite (10) including two skins (14) of composite material bonded on either side of a core (12) having the form of a honeycomb type panel, including a step of firing the skins (14) onto the core (12) to simultaneously carry out hardening of the skins (14) and bonding of the skins (14) with the core (12), characterised in that it consists in placing a rigidifying layer (22) between the core (12) and at least one skin (14).

Abstract: An aircraft having propulsion units for both conventional aircraft flight in the atmosphere and for high-altitude operation as a rocket. The aircraft is divided into a payload compartment and a compartment containing rocket propulsion unit propellant or fuel, and includes a long transverse wing with a small back-sweep to favour lift in the dense layers of the atmosphere and to thus make it possible to climb to high altitudes at a subsonic speed before using the rocket propulsion units. The return flight portion is performed by gliding or controlled as for a conventional aircraft.

Abstract: A method (50) for detecting broadcast signals, transmitted by terrestrial sources (40) and received by a satellite (20), in individual signals obtained respectively from different individual antennas (24) of an antenna array (22) of the satellite, includes a first detection iteration (51a) and a second detection iteration (51b), each of the first and second detection iterations including a step (52) of forming, from the individual signals, virtual beams of different respective main radiation directions, and a step of searching for the presence of broadcast signals in the virtual beams. Furthermore, for at least one broadcast signal detected during the first detection iteration, the respective contributions of the at least one detected broadcast signal to the different individual signals are attenuated, relative to the first detection iteration, for all or part of the virtual beams formed during the second detection iteration. A system (10) for detecting broadcast signals is also described.

Abstract: A payload for a repeater satellite of a communication system. The repeater satellite being placed into drift orbit above the surface of a celestial body. The payload being configured to repeat data received from a stationary satellite above the surface of the celestial body towards a terminal substantially at the surface of the celestial body, and to repeat data received from the terminal towards the stationary satellite.

Abstract: According to the invention, the system comprises: at least three position beacons (3) arranged about said location (2) and emitting in the long-wave range, and an apparatus associated with the user (1) and including means for receiving, processing and displaying the information transmitted by said beacons (3).

Abstract: A method for making a temporary connection between two parts (10, 12), comprising the following successive steps: placing a connecting element (40, 40?) into an operating position wherein said connecting element surrounds the assembly formed by said parts and is subjected to an internal deformation strain; locking the position of said connecting element by stress-keeping means (52?) with controlled relief; connecting said connecting element (40, 40?) to each part (10, 12) by attaching means (36, 38); and wherein said internal deformation stress is at a sufficient level to enable the connecting element (40, 40?) to be unsecured from said parts (10, 12) by extending to a rest position, during a release control of said stress-keeping means (52?).

Abstract: According to the invention, a link is established between the fixed part (4A) and the removable part (4B) of an enclosure (4) in which the second satellite is previously enclosed, said link being such that said removable part (4B) remains attached to said fixed part (4A) when said removable part (4B), initially in a first position for which said enclosure (4) is closed and encloses said second satellite, lies in a second position for which said enclosure (4) is open and able to release said satellite.

Abstract: An apparatus for driving a pump for fueling a rocket engine of a space vehicle. The apparatus comprises an inertia wheel and a transmitting device to transmit a rotation of the inertia wheel to the pump. The apparatus further comprises a measuring device to measure the rotation speed of the inertia wheel a clutching device to decouple the wheel and the pump for a speed lower than a pre-determined speed lower, which is lower than the nominal rotation speed of the wheel. The invention is particularly applicable to a space vehicle comprising a rocket engine wherein the fuel supply system comprises at least one pump driven by the apparatus of the invention and a starting device to start the apparatus while the space vehicle is in flight.

Abstract: Each terminal wishing to access a communication service implemented in a communications network transmits an identifier of subscription to this service during a phase of registration (3.1; 3.2) with the network. With each service subscription identifier is associated a call identifier to enable calling the terminal registered via the network. A system (1.2, 1.3) intended to register at least one terminal (1.4) from amongst a plurality of terminals (1.3; 1.4) in a telephony network includes means for dynamically changing the service subscription identifier (3.11, 3.12, 3.13) and the associated call identifier (3.4, 3.5, 3.6), for at least one of said terminals, and means for re-registering (3.15) with said network each terminal for which the service subscription identifier and the associated call identifier have been dynamically changed.

Abstract: A method increases the toughness of a material obtained by curing a composition that includes at least one vinyl ester monomer. The method includes the incorporation into the composition of a sulfonated polyaromatic thermoplastic polymer, which is achieved by dissolving the vinyl ester monomer and the thermoplastic polymer in a reactive diluent in which they are both soluble. The resulting curable composition includes at least one vinyl ester monomer, and very high toughness materials can be made from it. A curable composition can include at least one vinyl ester monomer, a sulfonated polyaromatic thermoplastic polymer and a N-vinyl lactam. The compositions can be used in the aeronautical, space, railway, nautical, automotive industries, arms and other industries.

Abstract: According to the invention, this piece comprises: e base section piece (1) provided with a projecting longitudinal heel (4) delimiting a longitudinal groove (7), a longitudinal pyrotechnic cord laid in said groove; and a plurality of consecutive section piece portions (2) fixed one after the other to said base section piece (1) by first fixing means (9). Between the consecutive section piece portions (2) are second fixing means (18), distributed along said base section piece (1) and independent of said first fixing means (9), enabling said pyrotechnic cord to be fixed and positioned relative to said base section piece (1).

Abstract: The invention relates to a method and system for free-field optical transmission by means of laser signals, including setting a rate for encoding information that is useful for transmission on the basis of variations in a signal receiving characteristic belonging to a single communication session. The encoding rate is preferably dynamically adjusted during the communication session. An optimized compromise is thereby created between a useful rate that is high and a post-decoding bit error rate that is low. The method and the related system enable atmospheric conditions that can disrupt laser signal transmission to be taken into account in real time when said laser signals pass through part of the earth's atmosphere.

Abstract: Temporary connection and pyrotechnic separation device with a longitudinal axis (X) comprising a pyrotechnic expansion tube (14) mounted in a space (11) formed in a connection zone between a first (2) and second assembly (4) to be separated, the second assembly (4) being formed of a stack of plies (12.1, 12.2) bonded together, the two assemblies (2, 4) being connected to each other by two metal parts (10.1, 10.2), said metal parts being fixed onto the first assembly and bonded onto the outer plies (12.1) of the second assembly (4), the bonding area between said outer ply (12.1) and the adjacent inner ply (12.2) is less than the bonding area between two inner plies (12.2) forming a fuse ply, such that, when the pyrotechnic expansion tube (14) is used, the outer ply (12.1) separates from the adjacent inner ply.

Abstract: An afterbody device for a spacecraft fitted with at least one rocket engine at the rear of the craft includes at least one movable cover element designed to take a first position, masking and reducing the vehicle's rear drag, where it prolongs the vehicle's fuselage around at least one part of a rocket engine nozzle of the vehicle and extends beyond the rear of the vehicle's fuselage, and to take a second position fully deployed, increasing the vehicle's aerodynamic drag.

Abstract: According to the invention, in accordance with a servo loop, the attitude (?M) of the craft (1) is measured in the vicinity of the rear end (1R) of said craft, then the orientation (?) of propulsion means (2), which can be oriented relative to said rear end (1R), is adjusted as a function of said attitude measurement (?M) in such a way that said craft (1) is stabilised on its flight path.