A ceramic composite tubular structure includes a monolithic ceramic preform being tubular-shaped created using an additive manufacturing process. The monolithic ceramic preform includes a first end, a second end, an inner surface, and an outer surface. The monolithic ceramic preform includes one or more apertures formed between the inner surface and the outer surface where at least one of the one or more apertures is open to at least one of the first end or the second end. An inner face sheet is formed on the inner surface of the monolithic ceramic preform by a first quantity of ceramic matrix composite plies. An outer face sheet is formed on the outer surface of the monolithic ceramic preform by a second quantity of ceramic matrix composite plies.

A technical test method for evaluating at least one operating parameter of a device over a sequence of a plurality of operating stages, each stage corresponding to a stable value of at least one operating setpoint of the device. The method including at least sampling values of the at least one operating parameter over time, filtering the sampled values in order to obtain a filtered signal for each operating parameter, calculating the variance of the sampled values for each operating parameter in a sampling window during the operating stage, calculating the absolute value of the time derivative of the filtered signal for each operating parameter, and changing the value of the at least one operating setpoint when, for each operating parameter, the variance of the sampled values and the absolute value of the time derivative of the filtered signal are less than respective predetermined lower thresholds.

A technical test method for evaluating at least one operating parameter of a device over a sequence of a plurality of operating stages, each stage corresponding to a stable value of at least one operating setpoint of the device. The method including at least sampling values of the at least one operating parameter over time, filtering the sampled values in order to obtain a filtered signal for each operating parameter, calculating the variance of the sampled values for each operating parameter in a sampling window during the operating stage, calculating the absolute value of the time derivative of the filtered signal for each operating parameter, and changing the value of the at least one operating setpoint when, for each operating parameter, the variance of the sampled values and the absolute value of the time derivative of the filtered signal are less than respective predetermined lower thresholds.

A method of controlling the pressure (PGC) and a mixture ratio of a rocket engine from a pressure setpoint (PGCc) and from a mixture ratio setpoint (RMc), the method comprising regulation delivering control signals for two control valves (VR1, VR2) of said engine, the regulation using a pressure feedback loop. The method further comprises determining an estimated value for the mixture ratio (RMe) used by said regulation, the estimated value for the mixture ratio being obtained by a model that delivers mixture ratio values as estimated from at least one of the two control valve control signals and/or from the measured pressure.

The invention also provides a control device.

A rocket motor assembly (3) for use with an aircraft ejection seat comprises a rocket motor (4) having a rocket motor housing (5) and an exhaust outlet (6-9) to permit exhaust gas to be output from the rocket motor (4) along a thrust vector. The rocket motor assembly (3) comprises a first rotational coupling (12) which is configured to rotationally couple a first part (13) of the rocket motor housing (5) to a support structure (10) and a releasable coupling (14) which is configured to releasably couple a second part (15) of the rocket motor housing (5) to the support structure (10). The releasable coupling (14) is configured to release the second part (15) of the rocket motor housing (5) to permit the rocket motor housing (5) to rotate about the rotational coupling (12) to change the angle of the thrust vector of exhaust gas output from the exhaust outlet (6-9).

Electric aircraft power plants and associated methods are provided. One power plant includes an emergency power unit (EPU) for providing electric power in the event of a malfunction of a battery pack of an electric aircraft to permit the electric aircraft to make an emergency maneuver. The EPU includes a rocket engine for generating a stream of exhaust fluid using a rocket propellant, a turbine operatively connected to extract energy from the stream of exhaust fluid generated by the rocket engine, and an electric generator operatively connected to be driven by the turbine and to supply electric power to an electric motor propelling the electric aircraft.

The present subject matter overcomes the deficiencies in the prior art by introducing or generating charged particles in an air stream and manipulating the air stream with magnetic fields operating on the charged particles. Embodiments of the present subject mater compress the air stream by accelerating charged particles with a moving magnetic field, where the magnetic field has a velocity perpendicular to its flux lines. The increased velocity of the charged particles increases the statistical mean particle velocity and thereby increases the pressure in the air stream. The compressed air stream is then heated and expanded through a second magnetic field. The expansion of the air stream substantially increases the velocity of the air stream and the charged particles therein. The interaction of the high velocity charged particles and the magnetic field imparts a force perpendicular to the flux lines, this force powers the movement of the magnetic field.

A rocket fueling system includes an insulated jacket configured to removably couple to at least a portion of a rocket and form an enclosed space between the insulated jacket and the at least the portion of the rocket. The rocket fueling system also includes a cryogen inlet in the insulated jacket. The cryogen inlet is configured to receive a cryogen into an interior chamber of the insulated jacket. The rocket fueling system further includes a cryogen outlet in the insulated jacket. The cryogen outlet is configured to provide the cryogen from the interior chamber in the insulated jacket to the at least the portion of the rocket in the enclosed space. The rocket fueling system still further includes a gas outlet in the insulated jacket configured to exhaust the cryogen from the enclosed space, and a flammable gas sensor configured to detect a flammable gas at the gas outlet.

The disclosed methods, systems, and kits provide the ability to deliver entire clean sheet designs from concept to first hot fire in under six weeks with instant specific impulses above 330 seconds in some of our engines. In examples, thrusters can be delivered that are at less than half of the mass budget allowable for them and they can be delivered in weeks.

The disclosed methods, systems, and kits provide the ability to deliver entire clean sheet designs from concept to first hot fire in under six weeks with instant specific impulses above 330 seconds in some of our engines. In examples, thrusters can be delivered that are at less than half of the mass budget allowable for them and they can be delivered in weeks.