Abstract: A system includes a housing for a gas turbine engine, and a fan disposed in the housing to rotate coaxially with a gas turbine included in the housing. The system also includes an inlet guide vane disposed in the housing in axial alignment with the fan and configured to have an open position where a first flow of air is received by the fan through the inlet guide vane, and a closed position where airflow through the inlet guide vane is obstructed. The system further includes a heat exchanger disposed in a supply passage in fluid communication with a second flow of air received by the fan. The second flow of air is received by the fan via the supply passage with the inlet guide vane in the open position or in the closed position.

Abstract: A gas turbine engine system includes a gas turbine engine having a fan bypass duct, a heat exchanger system, and a flow transfer unit configured to selectively allow or preclude flow between the fan bypass duct and the heat exchanger system. A controller is coupled to and configured to vary the state of one or more of a fan exit nozzle, a heat exchanger exit nozzle, and a flow control valve controlling flow between the fan bypass duct and the heat exchanger system.

Abstract: A system includes a housing for a gas turbine engine, and a fan disposed in the housing to rotate coaxially with a gas turbine included in the housing. The system also includes an inlet guide vane disposed in the housing in axial alignment with the fan and configured to have an open position where a first flow of air is received by the fan through the inlet guide vane, and a closed position where airflow through the inlet guide vane is obstructed. The system further includes a heat exchanger disposed in a supply passage in fluid communication with a second flow of air received by the fan. The second flow of air is received by the fan via the supply passage with the inlet guide vane in the open position or in the closed position.

Abstract: A gas turbine engine system includes a gas turbine engine having a fan bypass duct, a heat exchanger system, and a flow transfer unit configured to selectively allow or preclude flow between the fan bypass duct and the heat exchanger system. A controller is coupled to and configured to vary the state of one or more of a fan exit nozzle, a heat exchanger exit nozzle, and a flow control valve controlling flow between the fan bypass duct and the heat exchanger system.

Abstract: A method for operation of a hybrid propulsion system is provided that includes providing a hybrid propulsion system including a gas turbine engine, an electrical system, and a controller configured to cause the gas turbine engine to produce a first mechanical power output and to cause the electrical system to produce a second mechanical power output. The method further includes causing the gas turbine engine to produce the first mechanical power output and causing the electrical system to produce the second mechanical power output, which causes a drive shaft of the gas turbine engine to rotate. The method further includes decreasing production of the first mechanical power output when a combination of the first mechanical power output and the second mechanical power output for take-off or climb is a predetermined percentage of a predetermined parameter of the gas turbine engine.

Abstract: A method for operation of a hybrid propulsion system is provided that includes providing a hybrid propulsion system including a gas turbine engine, an electrical system, and a controller configured to cause the gas turbine engine to produce a first mechanical power output and to cause the electrical system to produce a second mechanical power output. The method further includes causing the gas turbine engine to produce the first mechanical power output and causing the electrical system to produce the second mechanical power output, which causes a drive shaft of the gas turbine engine to rotate. The method further includes decreasing production of the first mechanical power output when a combination of the first mechanical power output and the second mechanical power output for take-off or climb is a predetermined percentage of a predetermined parameter of the gas turbine engine.

Abstract: According to one aspect, a method of releasing a fan blade for testing a turbofan engine includes arranging an external shaped charge about an airfoil and modifying the airfoil by extricating one or more portions of material from one or more sides of the airfoil. The method further includes detonating the external shaped charge such that the airfoil is released at a selected time.

Abstract: According to one aspect, a method of releasing a fan blade for testing a turbofan engine includes providing an internal passage with a constant arc through an airfoil arranged about a blisk such that the constant arc of the internal passage aligns with a contour of the blisk. The method further includes packing the internal passage with a charge, modifying the airfoil such that the airfoil is released from the blisk evenly along a chordwise length of the airfoil, and detonating the charge such that the airfoil is released from the blisk at a selected time.

Abstract: A shaft balancing assembly comprising a nose cone and a plurality of balance weights. The nose cone is mounted to a rotatable shaft of a turbine machine via a plurality of elongated fasteners such that a central axis of the nose cone is alighted with the rotatable shaft. The nose cone comprises a flange extending axially from a leading tip to a trailing edge and a plurality of apertures each adapted to receive a balancing weight and an elongated fastener. The nose cone flange is formed from a filament wound composite material and has a uniform thickness.

Abstract: According to one aspect, a method of releasing a fan blade for testing a turbofan engine includes providing an internal passage with a constant arc through an airfoil arranged about a blisk such that the constant arc of the internal passage aligns with a contour of the blisk. The method further includes packing the internal passage with a charge, modifying the airfoil such that the airfoil is released from the blisk evenly along a chordwise length of the airfoil, and detonating the charge such that the airfoil is released from the blisk at a selected time.

Abstract: According to one aspect, a method of releasing a fan blade for testing a turbofan engine includes arranging an external shaped charge about an airfoil and modifying the airfoil by extricating one or more portions of material from one or more sides of the airfoil. The method further includes detonating the external shaped charge such that the airfoil is released at a selected time.

Abstract: A shaft balancing assembly comprising a nose cone and a plurality of balance weights. The nose cone is mounted to a rotatable shaft of a turbine machine via a plurality of elongated fasteners such that a central axis of the nose cone is alighted with the rotatable shaft. The nose cone comprises a flange extending axially from a leading tip to a trailing edge and a plurality of apertures each adapted to receive a balancing weight and an elongated fastener. The nose cone flange is formed from a filament wound composite material and has a uniform thickness.