An electricity generating apparatus capable of efficiently and safely charging a storage battery in an unmanned aerial vehicle during its flight and an unmanned aerial vehicle equipped with such apparatus. The apparatus is mounted in the vehicle, including a fuel tank which is a container body to reserve fuel, an electric generator unit connected to the fuel tank, tilt measurement means capable of measuring a tilt of the fuel tank, and electricity generation control means for controlling operation of generating electricity by the electric generator unit, wherein the electric generator unit is capable of charging a storage battery in the vehicle during flight, and the electricity generation control means drives the electric generator unit when a tilt angle of the fuel tank indicated by the tilt measurement means is within a safe angle which is a predetermined threshold angle, as well as an unmanned aerial vehicle equipped with such apparatus.

A gas turbine engine includes a core engine assembly including a compressor section communicating air to a combustor section where the air is mixed with fuel and ignited to generate a high-energy gas flow that is expanded through a turbine section. The turbine section is coupled to drive the compressor section. A propulsor section aft of the core engine is driven by the turbine section. An exhaust duct routing exhaust gases around the propulsor section. The exhaust duct includes an inlet forward of the propulsor section, an outlet aft of the turbine section and a passageway between the inlet and the outlet. An aircraft and exhaust duct are also disclosed.

An aircraft propulsion system in which a combustion engine is arranged to drive an electrical generator. An electrical energy store is provided within the system. A propulsive rotor is arranged to be driven by an electric motor and a controller selectively varies the supply of power to the electric motor from the generator and/or energy store in dependence on one or more property of a vapor trail resulting from the engine exhaust flow. The controller may also control the supply of power to the energy store for charging.

A propulsion system for an aircraft is provided having a propulsion engine configured to be mounted to the aircraft. The propulsion engine includes an electric machine defining an electric machine tip speed during operation. The propulsion system additionally includes a fan rotatable about a central axis of the electric propulsion engine with the electric machine. The fan defines a fan pressure ratio, R.sub.FP, and includes a plurality of fan blades, each fan blade defining a fan blade tip speed. The electric propulsion engine defines a ratio of the fan blade tip speed to electric machine tip speed that is within twenty percent of the equation, 1.01R.sub.FP0.311, such that the propulsion engine may operate at a desired efficiency.

An aircraft includes a fuselage extending between a forward end and an aft end. The aircraft additionally includes a propulsor mounted to the fuselage at the aft end of the fuselage, the propulsor including an outer nacelle and the outer nacelle defining an inlet. Additionally, the aircraft includes a deployable assembly attached to at least one of the fuselage or the outer nacelle, the deployable assembly movable between a stowed position and an engaged position. The deployable assembly alters an airflow towards the propulsor or into the propulsor through the inlet defined by the outer nacelle when in the engaged position to increase an efficiency of the aft fan and/or of the aircraft.

An aircraft includes a fuselage, a forward wing assembly, and aft wing assembly, and a propulsion system. The propulsion system includes a first primary thrust propulsor and a first secondary thrust propulsor, the first primary thrust propulsor being different than the first secondary thrust propulsor. Both the first primary thrust propulsor and the first secondary thrust propulsor are mounted to the same one of: a starboard side of the aft wing assembly, a port side of the aft wing assembly, a starboard side of the forward wing assembly, or a port side of the forward wing assembly.

The present disclosure is directed to an aerodynamic inlet guide vane assembly for reducing airflow swirl distortion entering an aft fan mounted to a fuselage of an aircraft. Further, the inlet guide vane assembly is configured for mounting to fan shaft and a nacelle of the aft fan. The inlet guide vane assembly includes a plurality of inlet guide vanes grouped into a plurality of inlet guide vane groups. Each of the inlet guide vanes has a shape and an orientation corresponding to airflow conditions entering the fan. Further, the inlet guide vane groups are spaced circumferentially around the central axis as a function of the airflow conditions entering the fan.

A hybrid power system for a vertical takeoff and landing (VTOL) aircraft including a first power source operable to provide a power output for at least a forward flight mode; and a second power source configured to provide a high specific power output for an altitude adjustment flight mode, the second power source including an auxiliary gas generator coupled to a turbine and a drive system. In other aspects, there is provided a VTOL aircraft and methods for providing power to a VTOL aircraft.

A reversible electrical machine (1) comprising: a first electrical device (10) having a first stator (11) and a first rotor (12); a second electrical device (20) including a second rotor (22) and a second stator (21) together with an outlet shaft (50) and first disengageable coupling means (30) enabling said first and second rotors (12, 22) to be associated and dissociated in rotation. Said reversible electrical machine (1) also includes second disengageable coupling means (40) that are disengageable under a predetermined force and that mechanically connect said second rotor (22) to said outlet shaft (50). Said first electrical device (10) is a motor for transmitting high mechanical power to said outlet shaft (50), while said second electrical device (20) is a motor-generator for operating in motor mode to transmit additional mechanical power to said outlet shaft (50), and in generator mode for receiving mechanical power from said outlet shaft (50).

The present disclosure concerns an electrical interconnect system for a vehicle such as an aircraft or marine/submarine vessel. Example embodiments include a vehicle comprising: a first electrical generator; a second electrical generator; an engine arranged to drive the first and second electrical generators; a first electrical distribution system connected to the first electrical generator and arranged to distribute electrical power within the vehicle, the first electrical distribution system comprising a transmission path and a return path; a second electrical distribution system connected to the second electrical generator, the second electrical distribution system comprising a transmission path and a return path; an electric motor configured to provide propulsion for the vehicle and connected to the second electrical generator via the second electrical distribution system, wherein the return path of the second electrical distribution system provides a portion of the return path of the first electrical distribution system.