An electrical vertical take-off and landing (eVTOL) aircraft includes a plurality of electrical propulsion units (EPUs), each EPU having a propeller or a fan configured to be driven to rotate by an electrical motor arranged to receive electrical power from a respective power electronics converter. Each power electronics converter includes a converter commutation cell having a power circuit and a gate driver circuit, the power circuit including at least one power semiconductor switching element and at least one capacitor. At least one terminal of each power conducting switching element is connected to at least one electrically conductive layer of a multi-layer planar carrier substrate at an electrical connection side of a power semiconductor prepackage, which includes at least one electrically conductive layer located on an opposite side of the power semiconductor switching element to the electrical connection side of the power semiconductor prepackage.

A modular autonomous aerial passenger vehicle is provided to automatically transport any person or luggage or capable of being used by the defense organizations for monitoring without any interference or need of human pilot. The autonomous aerial vehicle is comprising of an aerodynamic main body having 4 fixed arms each and 2 foldable arms each of which further having a pair of propellers coupled at the edge of each foldable arm, one at the top and one at the bottom. Further, the autonomous aerial vehicle further includes a power management system; safety system; interior cockpit having a HMI and seating arrangement, where the HMI is a brain computer interface that acquires signals from the brain and analyses them to convert it into commands. It includes a display unit and manual control unit; primary and auxiliary battery modules, flight control unit, plurality of sensors and cameras and other safety equipment for safe functioning of the present autonomous aerial vehicle.

A tail rotor isolation system for rotorcraft includes a secondary engine, first and second freewheeling units, an isolation assembly and a tail rotor system. The secondary engine is coupled to the input race of the first freewheeling unit. A main rotor system is coupled to the output race of the second freewheeling unit. The isolation assembly is coupled to the output race of the first freewheeling unit and has a fully engaged position coupling the input and output races of the second freewheeling unit and a partially engaged position coupled to the input race but decoupled from the output race of the second freewheeling unit. The tail rotor system is coupled to the input race of the second freewheeling unit such that in the partially engaged position of the isolation assembly, the overrunning mode of the second freewheeling unit isolates the tail rotor system from the main rotor system.

In one aspect a propulsion system comprises an engine and a drive assembly coupled to the engine, comprising a first driveshaft rotatable in a first direction about a first axis, a first fan coupled to the first driveshaft to rotate in the first direction, and a clutch assembly to selectively disengage the first fan from the first driveshaft. Other aspects may be described.

An aircraft including at least one wing system with two wings rigidly connected to a rotor provided with a swash plate control device. The wing system being able to change from a fixed wing configuration where the rotor is immobilised relative to the aircraft fuselage and the wings are oriented with their leading edge facing the direction of forward travel of the aircraft, to a rotating wing configuration where the rotor is rotated relative to the fuselage, and conversely, at least one of the wings is itself subjected, during the change-over from the fixed wing configuration to the rotating wing configuration, to a rotation on itself relative to the rotor in such a manner that the two wings of the wing system form blades having their leading edge oriented in the direction of rotation of the rotor.

An aircraft including at least one wing system with two wings rigidly connected to a rotor provided with a swash plate control device. The wing system being able to change from a fixed wing configuration where the rotor is immobilised relative to the aircraft fuselage and the wings are oriented with their leading edge facing the direction of forward travel of the aircraft, to a rotating wing configuration where the rotor is rotated relative to the fuselage, and conversely, at least one of the wings is itself subjected, during the change-over from the fixed wing configuration to the rotating wing configuration, to a rotation on itself relative to the rotor in such a manner that the two wings of the wing system form blades having their leading edge oriented in the direction of rotation of the rotor.

A tiltrotor aircraft comprising a wing carrying an engine on each wing half, and a fuselage-mounted third engine with a transmission system configured to drive each of the tilting rotors from the third engine. The engines may be any powerplant, including fore example, a reciprocating engine, a turbine engine, or an electric motor. The third engine is preferably controlled for best efficiency and best safety in engine failure cases.

An interconnect drive system for an aircraft has a driveline and clutch control system. The driveline comprises a shaft for each propulsion assembly, each shaft for transferring torque to and from the associated propulsion assembly, and a clutch operably coupling the shafts and configured for selective engagement. The clutch is capable of transferring a first amount of torque between the shafts while engaged and a second amount of torque between the shafts while disengaged. The system also has a clutch control system, comprising a computer operably connected to the clutch for controlling operation of the clutch and sensors for sensing torque applied to the driveline, output from the sensors being communicated to the computer. The computer commands operation of the clutch in response to the output from the sensors, the clutch being commanded to disengage to relieve a transient torque imbalance in the driveline.

An interconnect drive system for an aircraft has a driveline and clutch control system. The driveline comprises a shaft for each propulsion assembly, each shaft for transferring torque to and from the associated propulsion assembly, and a clutch operably coupling the shafts and configured for selective engagement. The clutch is capable of transferring a first amount of torque between the shafts while engaged and a second amount of torque between the shafts while disengaged. The system also has a clutch control system, comprising a computer operably connected to the clutch for controlling operation of the clutch and sensors for sensing torque applied to the driveline, output from the sensors being communicated to the computer. The computer commands operation of the clutch in response to the output from the sensors, the clutch being commanded to disengage to relieve a transient torque imbalance in the driveline.