Abstract: A turboprop gas turbine engine mountable to an aircraft has an engine core and a gearbox driving a propeller, the engine core and the gearbox being enclosed within a nacelle. The propeller is located rearward of the gearbox and the engine core relative to a direction of travel of the aircraft. An air intake is disposed within the nacelle and formed to direct ambient air into the engine core. The air intake includes an air inlet duct, having a forward-facing intake inlet receiving the ambient air, with an upstream section and a downstream section. The upstream section is in fluid communication with the intake inlet and extends downstream from the intake inlet. The downstream section fluidly connects to and directs air from the upstream section into the engine air inlet. A second air outlet duct is located within the nacelle and directs air into an air-cooled-oil-cooler (ACOC).

Abstract: Methods and systems for operating a rotorcraft comprising a plurality of engines are provided. A request to enter into an asymmetric operating regime (AOR), in which at least one active engine of the plurality of engines is operated in an active mode to provide motive power to the rotorcraft and at least one standby engine of the plurality of engines is operated in a standby mode to provide substantially no motive power, is obtained. Engine usage data for the plurality of engines, including at least one first engine and at least one second engine, is determined. Based on the engine usage data, one of the at least one first and second engines is operated as the at least one active engine for the AOR, and the other one of the at least one first and second engines is operated as the at least one standby engine for the AOR.

Abstract: The disclosure includes an apparatus comprising a diagnostic unit configured to communicate with a rules engine to determine whether a transmission detected in a vehicle is classified as driver wireless device usage based on passenger data indicating whether a passenger is present in the vehicle. The disclosure also includes a system comprising a shielding unit configured to transmit a noise signal to interrupt a transmission detected in a vehicle, and a diagnostic unit configured to communicate with a rules engine to determine whether the detected transmission is classified as driver wireless device usage based on the passenger data indicating whether a passenger is present in the vehicle, and activate a recording if the transmission is classified as driver wireless device usage.

Abstract: A gas turbine engine has an in-line mounted accessory gear box (AGB) and an accessory drivingly connected to the AGB, the accessory being oriented transversally to the engine centerline.

Abstract: Oil tanks for gas turbine engines and associated assembly methods are disclosed. In one exemplary embodiment, an oil tank is configured to be installed to occupy a radially-inner space defined by an annular radial air inlet duct of a reverse flow gas turbine engine. The oil tank may comprise a first tank portion and a second tank portion assembled together to cooperatively define an interior volume of the tank. An optional intermediate spacer may be disposed between the first tank portion and the second tank portion in order to form an oil tank of a larger size.

Abstract: Methods and systems for operating an aircraft having two or more engines are described. The method comprises receiving an engine availability confirmation when a set of engine parameters meet engine operating conditions for an asymmetric operating regime, receiving an aircraft availability confirmation when a set of aircraft parameters meet aircraft operating conditions for the asymmetric operating regime, outputting an availability message to a cockpit of the aircraft in response to receiving the engine availability confirmation and the aircraft availability confirmation, receiving a pilot-initiated request to operate the engine in the asymmetric operating regime, and commanding the engines to operate in the asymmetric operating regime in response to the pilot-initiated request.

Abstract: A clutch device for a gas turbine engine having a sliding coupling mounted to the engine and slidingly displaceable therein. The sliding coupling is mountable between the gearbox and the output shaft. The sliding coupling is continuously engageable with the gearbox and is selectively engageable with the output shaft to mechanically couple the output shaft to the gearbox. The sliding coupling is slidingly displaceable between a first position in which the sliding coupling is mechanically coupled to the output shaft to transmit a rotational drive of the output shaft to the gearbox, and a second position in which the sliding coupling is disengaged from the output shaft. A piston is disposed within the engine and acts on the sliding coupling to displace the sliding coupling to at least the second position.

Abstract: There is described a method for and system for starting at least one engine from a twin engine installation.

Abstract: A method of providing an engine family includes providing a first engine having a low pressure turbine driving a low pressure compressor at a first speed ratio, and a high pressure turbine driving a high pressure compressor. The method includes providing a second engine by changing the first speed ratio of the first engine to a second speed ratio.

Abstract: A multi-spool gas turbine engine comprises a low pressure (LP) spool and a high pressure (HP) spool independently rotatable about a central axis extending through an accessory gear box (AGB). The LP spool has an LP compressor, which is axially positioned between the HP compressor of the HP spool and the AGB. A tower shaft drivingly connects the HP spool to the AGB.

Abstract: An aircraft engine has a high pressure spool including a high pressure turbine drivingly connected to a high pressure compressor. A low pressure spool including a low pressure compressor is fluidly connected to the high pressure compressor. A low pressure turbine is drivingly connected to the low pressure compressor to drive the low pressure compressor. A load is drivingly connected to the low pressure turbine, the load consisting of one of a propeller and a helicopter rotor. A method of creating classes of an aircraft engine from an engine platform is disclosed.

Abstract: A turboprop or turboshaft engine comprises a first spool including a first compressor drivingly connected to a first turbine, the first turbine further drivingly connected to a load. The engine comprising a second spool including a second compressor drivingly connected to a second turbine, the second compressor fluidly connected to the first compressor to receive compressed air therefrom. The engine further comprises a third spool including a third compressor drivingly connected to a third turbine, the third compressor fluidly connected to the second compressor to receive compressed air therefrom.

Abstract: A method of operating a twin engine helicopter power plant, the power plant comprising: two turboshaft engines each having an engine shaft with a turbine at a distal end and a one-way clutch at a proximal end; a gear box having an input driven by the one way clutch of each engine and an output driving a helicopter rotor; a bypass clutch disposed between the proximal end of each engine shaft and the input of the gear box; and power plant management system controls for activating the bypass clutch; the method comprising: detecting when a rotary speed of an associated engine shaft is less than a rotary speed of the gear box input; activating the bypass clutch to drive the associated engine shaft using the rotation of the gear box input; and starting an associated engine by injecting fuel when the bypass clutch is activated.

Abstract: There is described a method for and system for starting at least one engine from a twin engine installation.

Abstract: The turboshaft engine for a rotorcraft includes a low pressure spool having a low pressure compressor and a low pressure turbine section, and a high pressure spool having a high pressure compressor and a high pressure turbine section. The spools are independently rotatable relative to one another. The low pressure compressor section includes a mixed flow rotor. A set of variable guide vanes (VGVs) are disposed upstream of each of the low pressure and high pressure compressors, the VGVs being configured to be independently operable relative to one another.

Abstract: A method of operating a multi-engine system of a rotorcraft includes, during a cruise flight segment of the rotorcraft, controlling a first engine to provide sufficient power and/or rotor speed demands of the cruise flight segment; and controlling a second engine to by providing a fuel flow to the second engine that is between 70% and 99.5% less than a fuel flow provided to the first engine. A turboshaft engine for a multi-engine system configured to drive a common load is also described.

Abstract: Electric power from the low spool of a turboshaft engine is transferred to drive the compressor of another turboshaft engine. This is used to assist in maintaining the other turboshaft idling while a single engine provides flight power or to increase acceleration for instance.

Abstract: Methods and systems for operating a turboprop engine having a high pressure spool and a low pressure spool rotating independently from one another. Each spool contains at least one compressor stage and the low pressure spool is connected to a propeller. The method comprises determining a target temperature-corrected rotational speed of the low pressure spool for a given set of operating parameters; and controlling a mechanical speed of the low pressure spool to maintain the temperature-corrected rotational speed of the low pressure spool substantially constant throughout at least a portion of a range of a power demand on the turboprop engine.

Abstract: A multi-spool gas turbine engine comprises a low pressure (LP) spool and a high pressure (HP) spool independently rotatable about a central axis extending through an accessory gear box (AGB). The LP spool has an LP compressor, which is axially positioned between the HP compressor of the HP spool and the AGB. A tower shaft drivingly connects the HP spool to the AGB.

Abstract: A reduction gearbox for an aircraft engine, including an input pinion configured to be driven by the aircraft engine, a input gear meshed with the input pinion, a drive gear meshed with the input gear, an output pinion, and an output gear meshed with the output pinion and configured to drive an output shaft of the aircraft engine. The reduction gearbox is selectively configurable between an engaged configuration where the input gear and output pinion are drivingly engaged and a disengaged configuration where the input gear is rotatable independently of the output pinion. The output shaft may drive a propeller and the gearbox may include a propeller brake. A method of driving a generator of a turboprop engine is also discussed.