A hybrid propulsion system includes a heat engine configured to drive a heat engine shaft. An electric motor is configured to drive an electric motor shaft. A transmission system includes at least one gearbox. The transmission system is configured to receive rotational input power from each of the heat engine shaft and the electric motor shaft and to convert the rotation input power to output power.

A power distribution controller for a hybrid aircraft is configured to continuously: obtain a state-of-charge (SoC) measurement for a battery of the hybrid aircraft; obtain a fuel level measurement for a secondary energy source of the hybrid aircraft; receive a control input indicating one of a throttle level or an operating mode for one or more motors of the hybrid aircraft; calculate a ratio of energy to source from each of the battery and the secondary energy source in order to operate the one or more motors of the hybrid aircraft based on the control input, the SoC measurement, and the fuel level measurement; and transmit a control signal that causes energy to be apportioned from the battery and the secondary energy source to the one or more motors based on the determined ratio.

Embodiments described herein relate to a vertical take-off and landing aircraft, specifically an electric or hybrid electric aircraft having a plurality of ducted fans. The aircraft includes a plurality of axially oriented fans, laterally oriented fans, forward air intakes, side exit ports and rear exhaust ports. The aircraft achieves flight by capturing air in the intakes and diverting the air through the axially oriented fans or the laterally oriented fans through the channels selectively.

Hybrid electric propulsion systems are described. The systems include a gas turbine engine having a low speed spool and a high speed spool. The low speed spool includes a low pressure compressor and a low pressure turbine and the high speed spool includes a high pressure compressor and a high pressure turbine. An electric machine is configured to augment rotational power of at least one of the high speed spool and the low speed spool. A controller is configured to control the electric machine to one of add or subtract rotational energy to or from at least one of the high speed spool and the low speed spool during a transition to or from an idle state of operation of the gas turbine engine.

Examples described herein provide a computer-implemented method that includes monitoring a hybrid electric turbine engine of an aircraft, the hybrid electric turbine engine including a first electric machine associated with a high speed spool and a second electric machine associated with a low speed spool. The method further includes receiving an indication of a failed electric machine, the failed electric machine being an electric machine on another hybrid electric turbine engine of the aircraft. The method further includes, responsive to detecting the failed electric machine, distributing power from one or more of the first electric machine or the second electric machine to a spool associated with the failed electric machine.

A hybrid electric propulsion system including: a gas turbine engine comprising a low speed spool and a high speed spool, the low speed spool comprising a low pressure compressor and a low pressure turbine, and the high speed spool comprising a high pressure compressor and a high pressure turbine; an electric motor configured to augment rotational power of the high speed spool or the low speed spool; at least one blade outer air seal positioned between an outer case of the high pressure turbine and a plurality of blades of the high pressure turbine; a clearance control system operably coupled to the at least one blade outer air seal, the clearance control system configured to vary a position of the at least one blade outer air seal with respect to the plurality of blades of the high pressure turbine; and a controller operably coupled to the electric motor and the clearance control system, wherein the controller is configured to operate the clearance control system based upon an operational state of the electric motor.

A hybrid electric propulsion system including: a gas turbine engine comprising a low speed spool, a high speed spool, and a combustor; a lubrication circuit comprising a bearing compartment, a supply pump, and a scavenger pump; an electric motor configured to augment rotational power of the low speed spool or the high speed spool; and a controller operable to: control the electric motor based upon a pressure differential between an interior of the bearing compartment and an exterior of the bearing compartment and to drive rotation of the low speed spool and/or the high speed spool via the electric motor responsive to a thrust command while fuel flow to the combustor is inhibited.

A VTOL aircraft has fixed wings and a rotor blade system for providing lift in active and passive modes thereof. Operation of the rotor blade system may be switched between the active mode in which the rotor blade system is driven by a power system of the aircraft and the passive mode in which the rotor blade system is not driven by the power system, the rotor blade system being configurable to provide lift in the passive mode during forward flight of the aircraft. The rotor blade system provides lift in the passive mode, allowing the fixed wings to be shorter than in the case where the rotor system provides lift during vertical take-off and landing but otherwise has no function, thus providing aircraft which is lighter, more compact and more efficient than similar aircraft of the prior art.

Variations of an aerial vehicle, all with capability of vertical take-off and landing (VTOL), with one variation comprising at least three engines, at least three rotors, a flight control system, battery, and propulsion system. The second VTOL aerial vehicle variation being a hybrid with engine-powered rotors and electric-powered rotors configured to work with a flight control system and battery. The first and second variations having the option of a genset system which recharges the battery. The third VTOL aerial vehicle variation being all-electric-powered rotors configured to work with a flight control system and a genset system which powers the rotors and/or recharges the battery.

A propulsion system (1) for a helicopter, comprising a turboshaft engine (2) with a linked turbine and an electric machine (3) capable of operating as an electric motor, the turboshaft engine (2) and the electric machine (3) being capable of driving in rotation at least one main rotor (5) intended to be coupled to a rotating wing (6) characterised in that it comprises means of coupling and decoupling (14) in rotation between a rotor (3a) of the electric machine (3) and a rotor (2a) of the turboshaft engine (2), the means of coupling and decoupling (14) being capable of allowing the rotor (2a) of the turboshaft engine (2) to be driven in rotation with the aid of the electric machine (3), in a first state of the propulsion system (1), and capable of allowing the rotor (2a) of the turboshaft engine (2) and the rotor (3a) of the electric machine (3) to be decoupled in rotation, in a second state of the propulsion system (1).