A flying vehicle propulsion system including a propulsor, a drive system and a heat exchanger. The drive system is arranged to drive the propulsor and the heat exchanger is arranged to thermally regulate at least part of the drive system. The propulsor is arranged to move fluid, thereby producing a propulsor fluid flow having a main direction. The system is arranged such that in a first operation configuration, at least part of the propulsor fluid flow is incident on the heat exchanger, thereby thermally regulating the at least part of the drive system.

A flying vehicle propulsion system including a propulsor, a drive system and a heat exchanger. The drive system is arranged to drive the propulsor and the heat exchanger is arranged to thermally regulate at least part of the drive system. The propulsor is arranged to move fluid, thereby producing a propulsor fluid flow having a main direction. The system is arranged such that in a first operation configuration, at least part of the propulsor fluid flow is incident on the heat exchanger, thereby thermally regulating the at least part of the drive system.

A motor integrated type fluid machine suctions a fluid from a suction port and discharges the suctioned fluid from a discharge outlet. The machine includes: a shaft portion provided at a center of a rotation axis; a rotating portion rotating around the shaft portion; an outer peripheral portion provided on an outer periphery of the shaft portion; and an outer peripheral drive motor rotating the rotating portion. The rotating portion includes a hub rotatably supported by the shaft portion, blades provided on an outer peripheral side of the hub and provided side by side in a circumferential direction of the rotation axis, and a rotating outer peripheral portion having an annular shape along the circumferential direction. A ratio of a rigidity of the rotating outer peripheral portion against a centrifugal force to a rigidity of the rotating portion against the centrifugal force is 50% to 95%.

A hybrid electric aircraft equipped with gyroscopic stabilization control is provided. In one aspect, a hybrid electric aircraft includes a turbo-generator having a gas turbine engine and an electric generator operatively coupled thereto for generating electrical power. The turbo-generator defines a rotation axis. The aircraft also includes one or more electrically-driven propulsors for producing thrust for the aircraft. In addition, the aircraft includes a pivot mount operatively coupled with the turbo-generator. To provide gyroscopic stabilization control of the aircraft, the pivot mount is controlled to adjust the rotation axis of the turbo-generator relative to a prime stability axis of the aircraft. Additionally or alternatively, a rotational speed of the turbo-generator can be changed to provide gyroscopic stabilization control of the aircraft.

A hybrid electric aircraft equipped with gyroscopic stabilization control is provided. In one aspect, a hybrid electric aircraft includes a turbo-generator having a gas turbine engine and an electric generator operatively coupled thereto for generating electrical power. The turbo-generator defines a rotation axis. The aircraft also includes one or more electrically-driven propulsors for producing thrust for the aircraft. In addition, the aircraft includes a pivot mount operatively coupled with the turbo-generator. To provide gyroscopic stabilization control of the aircraft, the pivot mount is controlled to adjust the rotation axis of the turbo-generator relative to a prime stability axis of the aircraft. Additionally or alternatively, a rotational speed of the turbo-generator can be changed to provide gyroscopic stabilization control of the aircraft.

An abnormality warning system provides an abnormality warning for multiple motor systems that drive a motor used correspondingly to each of multiple rotors included in an electric aircraft. The abnormality warning system includes an abnormality determination unit and a warning level setting unit. The abnormality determination unit determines an abnormal one of the motor systems. The warning level setting unit sets a warning level to warn abnormality, based on at least position information of the rotor in the electric aircraft or the usage of the rotor corresponding to a motor system determined to be abnormal by the abnormality determination unit.

A cable that includes a conductor defining a hollow interior, a casing surrounding the conductor, an electrical insulator positioned between the conductor and the casing, and a fluid positioned within the hollow interior of the conductor.

A cable that includes a conductor defining a hollow interior, a casing surrounding the conductor, an electrical insulator positioned between the conductor and the casing, and a fluid positioned within the hollow interior of the conductor.

In accordance with at least one aspect of this disclosure, there is provided a method of accelerating a gas turbine engine. The method includes adding torque to a core of the gas turbine engine to accelerate rotation of the core by controlling fuel flow to a plurality of fuel injectors of the gas turbine engine. The method also includes adding torque to the core by powering an electric machine that is operatively connected to the core. In embodiments, controlling fuel flow to the plurality of fuel injectors is based on feedback from the electric machine.

In accordance with at least one aspect of this disclosure, there is provided a system for aircraft power. The system includes a DC/DC converter having a DC input and a DC output and a switching circuit connecting the DC input to the DC output operable to vary voltage at the DC output. A control module is operatively connected to the switching circuit for variable control of the DC output. The control module includes machine readable instructions to cause the control module to receive input indicative of altitude and control the switching circuit to vary voltage of the DC output as a function of environmental conditions such as altitude and humidity. In embodiments the altitude sensor is operatively connected to the controller.