Abstract: A propulsion and electric power generation system includes a gas turbine propulsion engine, an electrical generator, an aircraft power distribution system, a plurality of auxiliary fans, and a controller. The gas turbine propulsion engine includes at least a low-pressure turbine coupled to a fan via a low-pressure spool, and the low-pressure turbine is configured to generate mechanical power. The electrical generator is directly connected to the low-pressure spool and generates a total amount of electrical power (Pe). The aircraft power distribution system receives a first fraction (Pa) of the total amount of electrical power. The auxiliary fans receive a second fraction (Pf) of the total amount of electrical power. The controller is configured to control a ratio of Pf to Pa (Pf/Pa) such that the ratio spans a range from less than 0.6 to at least 0.9.

Abstract: A propulsion and electric power generation system includes a gas turbine propulsion engine, an electrical generator, an aircraft power distribution system, a plurality of auxiliary fans, and a controller. The gas turbine propulsion engine includes at least a low-pressure turbine coupled to a fan via a low-pressure spool, and the low-pressure turbine is configured to generate mechanical power. The electrical generator is directly connected to the low-pressure spool and generates a total amount of electrical power (Pe). The aircraft power distribution system receives a first fraction (Pa) of the total amount of electrical power. The auxiliary fans receive a second fraction (Pf) of the total amount of electrical power. The controller is configured to control a ratio of Pf to Pa (Pf/Pa) such that the ratio spans a range from less than 0.6 to at least 0.9.

Abstract: A propulsion and electric power generation system includes a dual-spool turbofan gas turbine engine and an electrical generator. The dual-spool turbofan gas turbine engine includes at least a low-pressure turbine coupled to a fan via a low-pressure spool. The low-pressure turbine is configured to generate mechanical power. The electrical generator is directly connected to the low-pressure spool and is disposed downstream of the low-pressure turbine. A first fraction of the mechanical power generated by the low-pressure turbine is controllably supplied to the fan for propulsive power generation (Pt). A second fraction of the mechanical power generated by the low-pressure turbine is controllably supplied to the electrical generator for electrical power generation (Pe). A ratio of Pe to Pt (Pe/Pt), during operation of the dual-spool turbofan gas turbine engine, controllably spans a range from less than about 0.06 to at least 0.18.

Abstract: An accessory gear box for a gas turbine engine having a drive shaft with a rotational axis and a tower shaft coupled to the drive shaft is provided. The accessory gear box includes a first plurality of gears arranged, which extend along a first axis substantially parallel to the rotational axis of the drive shaft. The accessory gear box includes a second plurality of gears, which extend along a second axis. The accessory gear box includes a first shaft, with one of the first plurality of gears coupled to the first shaft, and one of the second plurality of gears coupled to a second shaft. The one of the second plurality of gears coupled to the first shaft includes a first engagement surface and a second engagement surface, and the second engagement surface is coupled to another one of the second plurality of gears to drive the second shaft.

Abstract: An accessory gear box for a gas turbine engine having a drive shaft with a rotational axis and a tower shaft coupled to the drive shaft is provided. The accessory gear box includes a first plurality of gears arranged, which extend along a first axis substantially parallel to the rotational axis of the drive shaft. The accessory gear box includes a second plurality of gears, which extend along a second axis. The accessory gear box includes a first shaft, with one of the first plurality of gears coupled to the first shaft, and one of the second plurality of gears coupled to a second shaft. The one of the second plurality of gears coupled to the first shaft includes a first engagement surface and a second engagement surface, and the second engagement surface is coupled to another one of the second plurality of gears to drive the second shaft.

Abstract: A gas turbine engine and an accessory gear box (AGB) are provided for. The gas turbine engine comprises a drive shaft, a compressor, a combustor and an exhaust turbine, where the exhaust turbine and the compressor are coaxially connected by the drive shaft. The gas turbine engine further comprises an engine casing of varying diameters circumferentially enveloping the compressor, the combustor and the exhaust turbine with a waist located between the compressor and the combustor. The gas turbine engine also includes an accessory gear box (AGB) attached to the engine casing at the waist, the AGB comprising a gear rotating on an axis extending in a transverse direction relative to that of the drive shaft.

Abstract: A gas turbine engine and an accessory gear box (AGB) are provided for. The gas turbine engine comprises a drive shaft, a compressor, a combustor and an exhaust turbine, where the exhaust turbine and the compressor are coaxially connected by the drive shaft. The gas turbine engine further comprises an engine casing of varying diameters circumferentially enveloping the compressor, the combustor and the exhaust turbine with a waist located between the compressor and the combustor. The gas turbine engine also includes an accessory gear box (AGB) attached to the engine casing at the waist, the AGB comprising a gear rotating on an axis extending in a transverse direction relative to that of the drive shaft.