An aircraft engine has a hollow driveshaft with a spool coaxial with the driveshaft and extending through the driveshaft to rotate independently of the driveshaft. A first harmonic cam is mounted on the driveshaft and a second spaced apart harmonic cam is mounted on the spool. At least one combustion cylinder is positioned between the cams along a combustion cylinder axis that is parallel with but radially spaced apart from the driveshaft. A piston assembly is disposed in each end of the combustion cylinder, with each piston assembly engaging a separate cam. A high-pressure compressor turbine is mounted on the driveshaft and driven by movement of a piston assembly, compressing air for the combustion cylinder. A rotating component is mounted on the spool and driven by movement of the other piston assembly. The rotating component may be another compressor turbine, a drive turbine, a fan or a propeller.

The present disclosure provides systems and methods for processing ammonia. The system may comprise one or more reactor modules configured to generate hydrogen from a source material comprising ammonia. The hydrogen generated by the one or more reactor modules may be used to provide additional heating of the reactor modules (e.g., via combustion of the hydrogen), or may be provided to one or more fuel cells for the generation of electrical energy.

An assembly for an aircraft turbojet engine is described. The assembly includes a central gas-exhaust element and a connecting flange interposed between, upstream, a metallic outlet of a turbojet engine and, downstream, the central element. The connecting flange consists of an annular part and flexible lugs having axially: a first end where the lug is connected to the annular part, and a second free end, projecting radially outwards from the first end and towards which the lug is fixed with the central element.

Preload sleeves and/or other retainers for a collet-mounted blade dovetail and/or other root are disclosed. An example turbofan for an engine includes a trunnion forming a socket for a root of a blade, a primary collet positioning the root with respect to the trunnion, and a radial preload retainer at least partially encircling the primary collet and applying a radial force with respect to the primary collet to support the primary collet positioning the root with respect to the trunnion.

The invention relates to a flight system having at least two actuated flapping wings (2), an actuated tail unit (9), a control device and an exoskeleton (1) for at least one person. The exoskeleton (1) is movable independently of the flapping wings (2). The control device is configured to receive motion sensor signals from the exoskeleton (1) and to use the motion sensor signals to define specified movement signals and to control the flapping wings (2) and/or the tail unit (9) by way of the specified movement signals. The specified movement signals can be defined such that the movements of the flapping wings (2) and/or of the tail unit (9) follow those of the exoskeleton (1).

The invention relates to a flight system having at least two actuated flapping wings (2), an actuated tail unit (9), a control device and an exoskeleton (1) for at least one person. The exoskeleton (1) is movable independently of the flapping wings (2). The control device is configured to receive motion sensor signals from the exoskeleton (1) and to use the motion sensor signals to define specified movement signals and to control the flapping wings (2) and/or the tail unit (9) by way of the specified movement signals. The specified movement signals can be defined such that the movements of the flapping wings (2) and/or of the tail unit (9) follow those of the exoskeleton (1).

Renewable fuel power systems for vehicles, such as aircraft, are provided. For example, a system includes a storage tank, a reactor module, a heat exchanger unit, and a combustion engine. The storage tank is configured to store ammonia in liquid form. The reactor module is in fluid communication with the storage tank. The reactor module is configured to extract hydrogen from the ammonia, and output fuel which includes the extracted hydrogen. The heat exchanger unit is configured to heat the ammonia which flows from the storage tank to an input of the reactor module, using heat which is extracted from the fuel that is output from the reactor module. The combustion engine is configured to combust the fuel provided by the reactor module, to thereby produce mechanical power.

Renewable fuel power systems for vehicles, such as aircraft, are provided. For example, a system includes a storage tank, a reactor module, a heat exchanger unit, and a combustion engine. The storage tank is configured to store ammonia in liquid form. The reactor module is in fluid communication with the storage tank. The reactor module is configured to extract hydrogen from the ammonia, and output fuel which includes the extracted hydrogen. The heat exchanger unit is configured to heat the ammonia which flows from the storage tank to an input of the reactor module, using heat which is extracted from the fuel that is output from the reactor module. The combustion engine is configured to combust the fuel provided by the reactor module, to thereby produce mechanical power.

An engine system of an aircraft includes an energy storage system, a gas turbine engine, and a controller. The gas turbine engine includes a low spool, a high spool, a low-spool generator operably coupled to the low spool, and a high-spool electric motor operably coupled to the high spool. The controller is configured to detect a braking condition of the aircraft, transfer power from the low-spool generator to the energy storage system based on the storage capacity state of the energy storage system, and transfer power to the high spool through the high-spool electric motor to support combustion in the gas turbine engine while a rotational speed of the low spool is reduced responsive to the low-spool generator extracting energy from the low spool.

An engine system of an aircraft includes an energy storage system, a gas turbine engine, and a controller. The gas turbine engine includes a low spool, a high spool, a low-spool generator operably coupled to the low spool, and a high-spool electric motor operably coupled to the high spool. The controller is configured to detect a braking condition of the aircraft, transfer power from the low-spool generator to the energy storage system based on the storage capacity state of the energy storage system, and transfer power to the high spool through the high-spool electric motor to support combustion in the gas turbine engine while a rotational speed of the low spool is reduced responsive to the low-spool generator extracting energy from the low spool.