A safety management system for an aircraft, or a propulsion system thereof including a fuel cell assembly and a combustion engine, may include various sensors and controllers configured to execute a safety action. At least one sensor is configured to detect at least one operating parameter of the propulsion system, and a controller is configured to determine that the at least one operating parameter has achieved a safety threshold and to execute a safety action when the at least one operating parameter has achieved the safety threshold. The safety action is configured to control operation of the fuel cell assembly and to control operation of the combustion engine.

The present disclosure provides methods and systems for fault detection for a speed sensing system of a multi-engine rotorcraft. A shaft speed for a first engine and a rotor speed for at least one rotor of the multi-engine rotorcraft are obtained. The shaft speed is compared to the rotor speed. When the shaft speed is greater than the rotor speed, a first fault in the speed sensing system is detected and a first speed sensing system fault signal is issued. When the shaft speed is less than the rotor speed, a determination is made regarding whether the first engine is coupled the at least one rotor based on a fuel flow to the first engine. A second fault in the speed sensing system is detected and a second speed sensing system fault signal is issued responsive to determining that the first engine is coupled to the at least one rotor.

The present disclosure provides methods and systems for fault detection for a speed sensing system of a multi-engine rotorcraft. A shaft speed for a first engine and a rotor speed for at least one rotor of the multi-engine rotorcraft are obtained. The shaft speed is compared to the rotor speed. When the shaft speed is greater than the rotor speed, a first fault in the speed sensing system is detected and a first speed sensing system fault signal is issued. When the shaft speed is less than the rotor speed, a determination is made regarding whether the first engine is coupled the at least one rotor based on a fuel flow to the first engine. A second fault in the speed sensing system is detected and a second speed sensing system fault signal is issued responsive to determining that the first engine is coupled to the at least one rotor.

An engine vibration monitoring and control system includes an aircraft autopilot and a flight management system (FMS). The FMS is in operable communication with the aircraft autopilot and is configured to determine when the aircraft autopilot is engaged and disengaged. The FMS is also adapted to receive vibration data from an engine vibration data source and is configured, upon determining that the aircraft autopilot is engaged, to: process the vibration data to determine when engine vibrations exceed one or more first thresholds, and when the engine vibrations exceed the one or more first thresholds, supply commands to the autopilot that cause the autopilot to take corrective actions to reduce the engine vibrations below the one or more first thresholds.

An engine vibration monitoring and control system includes an aircraft autopilot and a flight management system (FMS). The FMS is in operable communication with the aircraft autopilot and is configured to determine when the aircraft autopilot is engaged and disengaged. The FMS is also adapted to receive vibration data from an engine vibration data source and is configured, upon determining that the aircraft autopilot is engaged, to: process the vibration data to determine when engine vibrations exceed one or more first thresholds, and when the engine vibrations exceed the one or more first thresholds, supply commands to the autopilot that cause the autopilot to take corrective actions to reduce the engine vibrations below the one or more first thresholds.

In an aspect, a system for fixed-pitch lift configured for use in an electric aircraft includes a plurality of flight components mechanically coupled thereto, each configured to provide lift to the electric aircraft. The electric aircraft also includes a first pusher mechanically coupled to a first owing of the electric aircraft, wherein the first pusher is configured to provide forward flight to the electric aircraft, a second pusher mechanically coupled to a second wing of the electric aircraft, wherein the second pusher is configured to provide forward flight to the electric aircraft as well, a sensor that is configured to detect vertical lift and forward flight from a pilot control and generate a command datum, as a function of the pilot control, a flight controller which may include a computing device configured to receive the command datum and direct the electric aircraft, as a function of the command datum.

Components of a device may transmit signals between one another using piezo electric transducers (PETs). In a basic system, a first PET may be coupled to and/or in contact with a first location on a member. A second PET may be coupled to and/or in contact with a second location on the member and separated from the first PET by a distance. The first PET may receive a signal (e.g., an electrical voltage) and convert the signal to a mechanical force/stress causing vibration of the member. The vibration may propagate through the member to other locations about the member. The second PET receive the vibration and may convert the vibration back to the signal, such as by converting mechanical force/stress to the electrical voltage (i.e., the signal). A similar process may be performed in reverse to enable the first and second PET to provide two-way communication.

Components of a device may transmit signals between one another using piezo electric transducers (PETs). In a basic system, a first PET may be coupled to and/or in contact with a first location on a member. A second PET may be coupled to and/or in contact with a second location on the member and separated from the first PET by a distance. The first PET may receive a signal (e.g., an electrical voltage) and convert the signal to a mechanical force/stress causing vibration of the member. The vibration may propagate through the member to other locations about the member. The second PET receive the vibration and may convert the vibration back to the signal, such as by converting mechanical force/stress to the electrical voltage (i.e., the signal). A similar process may be performed in reverse to enable the first and second PET to provide two-way communication.

There is provided a system and a method for operating a multi-engine rotorcraft. When the rotorcraft is cruising in an asymmetric operating regime (AOR) at least one engine is an active engine and is operated in an active mode to provide motive power to the rotorcraft and at least one second engine is a standby engine and is operated in a standby mode to provide substantially no motive power to the rotorcraft, at least one of a power level of the at least one second engine is increased and at least one variable geometry mechanism of the at least one second engine is moved to shed any ice accumulation on the at least one second engine.

A system for autonomous flight of an electric vertical takeoff and landing (eVTOL) aircraft. The system may include a fuselage, a plurality of laterally extending elements, a plurality of propulsors, a flight controller, and a pilot override switch. The plurality of laterally extending elements are attached to the fuselage. The plurality of propulsors is attached to the plurality of laterally extending elements. The flight controller is communicatively connected to the pilot override switch. The flight controller is configured to identify a flight transition point, initiate rotation about an axis of the fuselage a as function of the flight transition point, and terminate rotation once the desired flight angle is reached.