An electrically powered propulsion system for a spacecraft includes a first center of gravity at a first time of operation and a second center of gravity at a second time of operation, where the second center of gravity is different from the first center of gravity. The electrically powered propulsion system includes a thruster realignment mechanism and at least two thrusters coupled to the thruster realignment mechanism. Each of the at least two thrusters has an individual thrust vector. The thruster realignment mechanism is adapted such that, in a first position, the individual thrust vectors of the at least two thrusters pass through the first center of gravity and that, in a second position, the individual thrust vectors of the at least two thrusters pass through the second center of gravity. The thruster realignment mechanism holds the first position in the event all of the at least two thrusters are without any failure. In addition, the thruster realignment mechanism realigns the thrusters to the second position in the event of at least one of (i) a failure of one of the at least two thrusters, and (ii) a predetermined time criterion is fulfilled.

An electrically powered propulsion system for a spacecraft includes a first center of gravity at a first time of operation and a second center of gravity at a second time of operation, where the second center of gravity is different from the first center of gravity. The electrically powered propulsion system includes a thruster realignment mechanism and at least two thrusters coupled to the thruster realignment mechanism. Each of the at least two thrusters has an individual thrust vector. The thruster realignment mechanism is adapted such that, in a first position, the individual thrust vectors of the at least two thrusters pass through the first center of gravity and that, in a second position, the individual thrust vectors of the at least two thrusters pass through the second center of gravity. The thruster realignment mechanism holds the first position in the event all of the at least two thrusters are without any failure. In addition, the thruster realignment mechanism realigns the thrusters to the second position in the event of at least one of (i) a failure of one of the at least two thrusters, and (ii) a predetermined time criterion is fulfilled.

An ablative thruster includes a nozzle configured to control a flow of thrust from the satellite. The ablative thruster also includes an ablative surface inside of the nozzle, configured to deflect the thrust at a predefined angle. The ablative surface is configured to ablate-away, leaving un-deflected thrust for a majority of the burn.

A motor assembly is provided for use with projectiles, such as munitions, having relatively low length to diameter ratios. The motor assembly has an aerospike nozzle and a casing disposed about the aerospike nozzle, where interior aerospike volume contains propellant and where walls of both the cowl of the casing and of the aerospike nozzle jointly define a combustion chamber.

A motor assembly is provided for use with projectiles, such as munitions, having relatively low length to diameter ratios. The motor assembly has an aerospike nozzle and a casing disposed about the aerospike nozzle, where interior aerospike volume contains propellant and where walls of both the cowl of the casing and of the aerospike nozzle jointly define a combustion chamber.

The invention relates to a combustion gas discharge nozzle for a rocket engine including a stationary part and a moving part extending from the stationary part, the moving part made using flaps positioned downstream from the stationary part and forming an extension of the nozzle, the nozzle including a sealing device extending between the fixed part and the moving part in the form of a flexible membrane withstanding a local temperature of the combustion gases at the nozzle outlet and connecting the end of the stationary part to a border of the flaps or petals forming the moving part, the flexible membrane forming an annular tubing, the sealing device being provided with a duct for injecting gas at the flexible membrane between the stationary part and the moving part extending the nozzle.

The invention relates to a combustion gas discharge nozzle for a rocket engine including a stationary part and a moving part extending from the stationary part, the moving part made using flaps positioned downstream from the stationary part and forming an extension of the nozzle, the nozzle including a sealing device extending between the fixed part and the moving part in the form of a flexible membrane withstanding a local temperature of the combustion gases at the nozzle outlet and connecting the end of the stationary part to a border of the flaps or petals forming the moving part, the flexible membrane forming an annular tubing, the sealing device being provided with a duct for injecting gas at the flexible membrane between the stationary part and the moving part extending the nozzle.

A liquid propellant rocket engine includes a combustion chamber that has a throat and a nozzle aft of the throat. The nozzle has a first nozzle section adjacent the throat and a second nozzle section aft of the first nozzle section. The first nozzle section includes active cooling features and the second nozzle section excludes any active cooling features. The first nozzle section is operative via at least the active cooling features to form a condensate that passively cools the second nozzle section.

A first jet tab and a second jet tab are symmetrically arranged with respect to a symmetry plane and have a symmetrical shape with respect to the symmetry plane, and are symmetrically driven with respect to the symmetry plane by a driving section. A distance between a tip of the first jet tab and a first rotation axis is larger than a distance between the first rotation axis and the symmetry plane. A distance between a tip section of the second jet tab and a second rotation axis is larger than a distance between the second rotation axis and the symmetry plane.

A first jet tab and a second jet tab are symmetrically arranged with respect to a symmetry plane and have a symmetrical shape with respect to the symmetry plane, and are symmetrically driven with respect to the symmetry plane by a driving section. A distance between a tip of the first jet tab and a first rotation axis is larger than a distance between the first rotation axis and the symmetry plane. A distance between a tip section of the second jet tab and a second rotation axis is larger than a distance between the second rotation axis and the symmetry plane.