A slinger combustor includes; a first compressed air line connected to a compressor and configured to supply compressed air; a first fuel line connected to a fuel storage and configured to supply fuel; a rotation shaft configured to rotate and inject the fuel supplied from the first fuel line; a main combustion chamber configured to receive the fuel injected from the rotation shaft and receive the compressed air from the first compressed air line; and a sub-combustion chamber configured to selectively discharge a flame generated in an inner space of the sub-combustion chamber to the main combustion chamber.

Methods and systems are provided for presenting an energy state associated with an aircraft with respect to an operating envelope region for a procedure to restart an engine of the aircraft. One method involves providing a graphical user interface display having a first reference axis corresponding to a first energy state parameter and a second reference axis corresponding to a second energy state parameter different from the first energy state parameter, providing a graphical representation of an operating envelope region associated with a procedure for starting an engine of the aircraft with respect to the first and second reference axes, obtaining current values for the first and second energy state parameters for the aircraft, and providing a graphical representation of the aircraft positioned with respect to the first and second reference axes based on the current values for the first and second energy state parameters.

Examples described herein provide a method for restarting an engine of an aircraft during a flight of the aircraft. The method includes detecting a shutdown of the engine. The method further includes setting a flag to prevent a quick-relight situation. The method further includes performing an auto-relight procedure to attempt to restart the engine. The method further includes, responsive to determining that the auto-relight procedure failed to restart the engine, selectively performing at least one of a windmilling restart of the engine or a starter assist restart of the engine.

Examples described herein provide a method for restarting an engine of an aircraft during a flight of the aircraft. The method includes detecting a shutdown of the engine. The method further includes setting a flag to prevent a quick-relight situation. The method further includes performing an auto-relight procedure to attempt to restart the engine. The method further includes, responsive to determining that the auto-relight procedure failed to restart the engine, selectively performing at least one of a windmilling restart of the engine or a starter assist restart of the engine.

An aircraft system includes a component configured to operate with a minimum power demand. The aircraft system also includes an auxiliary power unit including an engine. The auxiliary power unit is configured to power the component and to operate the engine in a plurality of operating modes including a power mode and a standby mode. The auxiliary power unit generates a first power output at least equal to the minimum power demand during the power mode. The auxiliary power unit generates a second power output less than the minimum power demand during the standby mode.

An aircraft system includes a component configured to operate with a minimum power demand. The aircraft system also includes an auxiliary power unit including an engine. The auxiliary power unit is configured to power the component and to operate the engine in a plurality of operating modes including a power mode and a standby mode. The auxiliary power unit generates a first power output at least equal to the minimum power demand during the power mode. The auxiliary power unit generates a second power output less than the minimum power demand during the standby mode.

Examples described herein provide a computer-implemented method that includes determining a thrust requirement to satisfy a desired glide slope. The method further includes determining, based on the thrust requirement, whether thrust matching can be maintained while operating a first gas turbine engine in a fuel-burning mode and operating a second gas turbine engine in an electrically powered mode. The method further includes, responsive to determining that thrust matching cannot be maintained, commanding fuel flow to a combustor of the second engine to cause the second gas turbine engine to operate in the fuel-burning mode.

Examples described herein provide a computer-implemented method that includes determining a thrust requirement to satisfy a desired glide slope. The method further includes determining, based on the thrust requirement, whether thrust matching can be maintained while operating a first gas turbine engine in a fuel-burning mode and operating a second gas turbine engine in an electrically powered mode. The method further includes, responsive to determining that thrust matching cannot be maintained, commanding fuel flow to a combustor of the second engine to cause the second gas turbine engine to operate in the fuel-burning mode.

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.