Systems and methods to control an amount of axial clearance within a clutch transmission system are disclosed. A propulsion system includes a clutch transmission system having clutch vibratory response clearance control logic configured to iteratively control the amount of axial clearance within the clutch transmission system so as to achieve a desired, e.g., consistent and/or limited, clutch vibratory response.

The present invention includes a hybrid propulsion system for an aircraft comprising: one or more turboshaft engines that provide shaft power and are capable of providing thrust; at least one of: one or more electrical generators or one or more hydraulic pumps connected to a shaft of the one or more turboshaft engines; and at least two rotatable nacelles, each nacelle housing at least one of: one or more electric motors or one or more hydraulic motors each connected to a proprotor, wherein the electric motor is electrically connected to the electric generator, or the hydraulic motor is connected to the hydraulic pump, respectively, wherein the proprotors provide lift whenever the aircraft is in vertical takeoff and landing and stationary flight, and provide thrust whenever the aircraft is in forward flight.

A thrust unit for a propulsion device includes a thrust engine, arranged to provide a thrust force oriented in a direction so as to provide substantially vertical take-off and landing capability, and a deflector assembly comprising a pair of deflecting elements arranged to selectively divert the ejected fluid and movably mounted in the fluid outlet path. In order to reduce the bulk of the thrust unit and improve reliability and responsiveness, the invention relates more particularly to the positioning of the deflecting elements opposite the ejected fluid.

A propulsion system for an aircraft may include two coaxial propellers to operate in two different flight conditions. Each propeller may be attached to a driveshaft via corresponding one-way devices that allow each propeller to be driven in one direction but spin freely in the other direction. A reversible motor may selectively rotate the driveshaft in one direction to cause one propeller to operate while the other spins freely. For example, one propeller may be operated for one flight condition (such as vertical lift) and the other propeller may be operated for another flight condition (such as horizontal flight). Another propulsion system may include a propeller, a one-way bearing, a motor, and a generator. The one-way bearing may allow the motor to drive the propeller in one direction and to spin freely in the other direction to drive the generator with incoming airflow during a gliding phase of flight.

A gas turbine engine system is disclosed herein. The gas turbine engine system includes an engine core configured to discharge air through an exhaust nozzle along a central axis and a thrust director arranged near the exhaust nozzle and configured to redirect the discharge air by applying flow to the discharge air near the exhaust nozzle.

A hybrid propulsion system for an aircraft comprising: an engine disposed within a fuselage of the aircraft, two electrical generators disposed within the fuselage and connected to the engine, and two nacelles. Each nacelle comprises a proprotor, and two electric motors connected to the proprotor. Each electrical generator is connected to the two electric motors in each nacelle. The proprotors provide lift for vertical takeoff and landing in a helicopter mode. A fan is coupled to the fuselage and connected to two additional electric motors. Each additional electric motor is connected to one of the two electric generators.

A hybrid propulsion system for an aircraft comprising: an engine disposed within a fuselage of the aircraft, two electrical generators disposed within the fuselage and connected to the engine, and two nacelles. Each nacelle comprises a proprotor, and two electric motors connected to the proprotor. Each electrical generator is connected to the two electric motors in each nacelle. The proprotors provide lift for vertical takeoff and landing in a helicopter mode. A fan is coupled to the fuselage and connected to two additional electric motors. Each additional electric motor is connected to one of the two electric generators.

A propulsion system includes a first propulsor rotor, a second propulsor rotor and a gas turbine engine core. The first propulsor rotor is configured to generate propulsive thrust. The second propulsor rotor is configured to generate propulsive lift. The gas turbine engine core includes a compressor section, a combustor section, a turbine section and a rotating structure. The rotating structure includes a turbine rotor within the turbine section. The gas turbine engine core is configured to rotate the rotating structure at a first rotational speed during a first mode to drive the first propulsor rotor to generate the propulsive thrust. The gas turbine engine core is configured to rotate the rotating structure at a second rotational speed during a second mode to drive the second propulsor rotor to generate the propulsive lift. The second rotational speed may be less than eighty percent of the first rotational speed.