An aircraft wing including: a wingbox; a fuel tank; a fuel cell system with a fuel cell; a fuel line configured to deliver fuel from the fuel tank to the fuel cell system; a propulsion system carried by the wingbox; and an electrical power line configured to deliver electrical power from the fuel cell system to the propulsion system. The fuel tank and the fuel cell system are located inside the wingbox, and the propulsion system is located outside the wingbox.

A propulsor fan array having reduced noise emission is disclosed. The propulsor fan array includes a plurality of propulsor fans that collectively generate thrust. Each of the propulsor fans include a blade fan having a plurality of blades. The plurality of blades are tensioned at tips of the plurality of blade fans such that a pitch of the blades during thrust generation is substantially the same as a pitch of the blades at rest. By tensioning the tips of the blades, an angle of the blades is maintained during operation of the propulsor fan thereby reducing noise that may result from changes in the angle of the blades.

A propulsor fan array having reduced noise emission is disclosed. The propulsor fan array includes a plurality of propulsor fans that collectively generate thrust. Each of the propulsor fans include a blade fan having a plurality of blades. The plurality of blades are tensioned at tips of the plurality of blade fans such that a pitch of the blades during thrust generation is substantially the same as a pitch of the blades at rest. By tensioning the tips of the blades, an angle of the blades is maintained during operation of the propulsor fan thereby reducing noise that may result from changes in the angle of the blades.

A cooling system includes a plurality of heat exchanger assemblies corresponding to a plurality of battery packs and a fluid conveyance assembly. Each heat exchanger assembly includes a first heat exchanger inlet-outlet and a second heat exchanger inlet-outlet configured to receive a heat transfer fluid or discharge the heat transfer fluid. The fluid conveyance assembly is coupled to the heat exchanger assemblies and configured to circulate the heat transfer fluid in parallel to the heat exchanger assemblies in a U-flow scheme with an inlet and an outlet of the heat transfer fluid arranged at the same location. The fluid conveyance assembly includes a plurality of flow restrictors configured to balance the heat transfer fluid flowing into the heat exchanger assemblies. The heat transfer fluid flows through the corresponding flow restrictor before flowing into the corresponding heat exchanger assembly of the battery pack.

A hydrogen circulation system for use with a fuel cell stack includes a supply line for receiving hydrogen gas from a supply of hydrogen, a fuel cell for receiving hydrogen gas from the supply line, an excess hydrogen line for receiving excess hydrogen from the fuel cell, and a turbocharger coupled to the excess hydrogen line and the supply line, to receive excess hydrogen from the excess hydrogen line, compress it, and return it to the supply line, the turbocharger being powered in use by hydrogen gas from the supply line.

An electric drive with a fan for an aircraft, wherein the electric drive comprises an electric machine, in particular a permanently excited electric machine, with a stator and a rotor, and the propeller comprises a shaft and rotor blades, wherein the rotor blades are attached to the shaft, the rotor comprises a laminated core and magnets, wherein the laminated core forms an annular arrangement around the shaft, and the rotor blades, the shaft, the laminated core and the magnets are connected in a thermally conductive manner so that the rotor blades form a heat sink for the magnets.

An electric drive with a fan for an aircraft, wherein the electric drive comprises an electric machine, in particular a permanently excited electric machine, with a stator and a rotor, and the propeller comprises a shaft and rotor blades, wherein the rotor blades are attached to the shaft, the rotor comprises a laminated core and magnets, wherein the laminated core forms an annular arrangement around the shaft, and the rotor blades, the shaft, the laminated core and the magnets are connected in a thermally conductive manner so that the rotor blades form a heat sink for the magnets.

Systems and methods relate to electric propulsor fault detection. An exemplary system includes at least a first inverter configured to accept a direct current and produce an alternating current, a first propulsor, a first motor operatively connected with the first propulsor and powered by the alternating current, and at least a noise monitoring circuit electrically connected with the direct current and configured to detect electromagnetic noise and disengage the at least an inverter as a function of the electromagnetic noise.

An aircraft system is provided that includes a propulsor rotor, a geartrain, a thermal engine, a drivetrain and an electric machine. The geartrain includes a power output, a first power input and a second power input. The power output is coupled to the propulsor rotor. The thermal engine is configured to drive rotation of the propulsor rotor through the geartrain. The thermal engine is coupled to the first power input. The drivetrain includes a first driveshaft and a second driveshaft. The first driveshaft is coupled to and between the second power input and the second driveshaft. The second driveshaft is angularly offset from the first driveshaft. The electric machine is configured to drive rotation of the propulsor rotor through the drivetrain and the geartrain. The second driveshaft is coupled to and between the first driveshaft and the electric machine.

This invention relates to a vertical take-off and landing (VTOL) aircraft, a method of controlling a VTOL aircraft, and a control system for controlling the VTOL aircraft. The aircraft comprises an airframe having a wing extending along a transverse axis and attached to a fuselage extending between a longitudinal axis of the aircraft, and an empennage or canard. An array of electric rotors is fixedly mounted to the airframe. Front and rear internal combustion engines are pivotably mounted to the fuselage and are displaceable between lift positions in which the front and rear rotors are oriented to provide vertical lift to the aircraft for vertical flight and propulsion positions in which the front and rear rotors are oriented to provide forward thrust to the aircraft for horizontal flight. The front and rear rotors provide a majority, or all, of the vertical lift to the aircraft during vertical flight.