In an aspect the current disclosure is directed to an electric aircraft, wherein the electric aircraft is comprised of a plurality of flight components and a flight controller. A plurality of flight components is comprised of a plurality of control surfaces, a plurality of lift propulsors, at least a thrust propulsor, and a plurality of electric motors configured to power the plurality of propulsors. The flight controller is communicatively connected to a pilot input and flight components. The flight controller is configured to receive control datum from a pilot input and generate an output datum as a function of the control datum.

A structural system for lifting cells, constructed of modular, lightweight framing supporting thin, lightweight, single-ply or laminated, air-impermeable membranes, that maintain near constant-volume under low pressure for aerostatic lift in lighter-than-air aircraft; a system for controlling that aerostatic lift in a single or a plurality of such lifting cells, using electrically-powered vacuum pumps and valves; and a system for recovering electrical energy expended during ascent by using the inflow of air into the lifting cells during descent to generate electricity.

A structural system for lifting cells, constructed of modular, lightweight framing supporting thin, lightweight, single-ply or laminated, air-impermeable membranes, that maintain near constant-volume under low pressure for aerostatic lift in lighter-than-air aircraft; a system for controlling that aerostatic lift in a single or a plurality of such lifting cells, using electrically-powered vacuum pumps and valves; and a system for recovering electrical energy expended during ascent by using the inflow of air into the lifting cells during descent to generate electricity.

A method is provided for operating a vehicle that includes rotors driven by actuators to cause the vehicle to move. The method includes determining rotational speeds at which to drive the rotors to achieve a controlled movement of the vehicle. The rotational speeds include a rotational speed for a rotor of a pair of the rotors driven by a pair of the actuators. The method includes monitoring the rotational speed to detect that the rotational speed has approached or reached a defined avoid band of rotational speeds, and biasing the rotational speed to produce at least one biased rotational speed for respective rotors of the pair that is outside the defined avoid band. The method includes generating commands for the actuators based on the rotational speeds, and modifying the commands including those of the commands for the pair of the actuators based on the at least one biased rotational speed.

A hybrid-electric propulsion system for an aircraft is provided herein that can include a propulsor and a turbomachine comprising a high pressure turbine drivingly coupled to a high pressure compressor through a high pressure spool. An auxiliary power unit can be operably coupled with a starter motor. An electrical system can comprise a first electric machine coupled to the turbomachine. The first electric machine can be separate from the starter motor. A controller can be configured to provide electrical power from an electric power source to the first electric machine to drive the first electric machine to start, or assist with starting, the turbomachine.

A hybrid-electric propulsion system for an aircraft is provided herein that can include a propulsor and a turbomachine comprising a high pressure turbine drivingly coupled to a high pressure compressor through a high pressure spool. An auxiliary power unit can be operably coupled with a starter motor. An electrical system can comprise a first electric machine coupled to the turbomachine. The first electric machine can be separate from the starter motor. A controller can be configured to provide electrical power from an electric power source to the first electric machine to drive the first electric machine to start, or assist with starting, the turbomachine.

A flight control system for an aircraft comprises a flight control computer system connected via a bus system with a plurality of bus nodes, which each are configured to at least one of controlling an associated aircraft device based on command messages received from the flight control computer system via the bus system and sending information messages to the flight control computer system via the bus system. The bus system is a redundant bus system comprising plural independent bus sub-systems, wherein each bus node is configured to communicate with the flight control computer system via two different bus sub-systems, wherein each bus node further is configured to communicate with the flight control computer system on basis of an associated predetermined bus communication protocol via a first bus sub-system and on basis of an associated predetermined bus communication protocol via a second bus sub-system.

A flight control system for an aircraft comprises a flight control computer system connected via a bus system with a plurality of bus nodes, which each are configured to at least one of controlling an associated aircraft device based on command messages received from the flight control computer system via the bus system and sending information messages to the flight control computer system via the bus system. The bus system is a redundant bus system comprising plural independent bus sub-systems, wherein each bus node is configured to communicate with the flight control computer system via two different bus sub-systems, wherein each bus node further is configured to communicate with the flight control computer system on basis of an associated predetermined bus communication protocol via a first bus sub-system and on basis of an associated predetermined bus communication protocol via a second bus sub-system.

A method, computer program and system are provided for calculating in an automatic manner a trajectory for rejoining a reference vertical profile of an aircraft. A reference vertical profile comprises a set of vertical constraints, and a method comprises a step of selecting an altitude constraint to be complied with, a step of calculating a vertical-profile prediction making it possible to comply with the constraint, a step of validating the vertical-profile prediction, if the vertical-profile prediction is validated, a step of applying the vertical-profile prediction, otherwise a step of determining the existence of a following altitude constraint to be complied with; if a following altitude constraint exists: a step of selecting a following altitude constraint to be complied with; a return to the step of detecting non-compliance with an altitude constraint; otherwise, a step of applying an exit procedure.

A method, computer program and system are provided for calculating in an automatic manner a trajectory for rejoining a reference vertical profile of an aircraft. A reference vertical profile comprises a set of vertical constraints, and a method comprises a step of selecting an altitude constraint to be complied with, a step of calculating a vertical-profile prediction making it possible to comply with the constraint, a step of validating the vertical-profile prediction, if the vertical-profile prediction is validated, a step of applying the vertical-profile prediction, otherwise a step of determining the existence of a following altitude constraint to be complied with; if a following altitude constraint exists: a step of selecting a following altitude constraint to be complied with; a return to the step of detecting non-compliance with an altitude constraint; otherwise, a step of applying an exit procedure.