Abstract: An aircraft propeller drive system has a gear to be driven by an engine and having a first plurality of teeth. A torsion bar has a first end driven by the gear and a second end rotatable relative to the first end about a torsion axis by a torsion angle. An output shaft is driven by the second end and is adapted for connection to a propeller. A clutch has a driven member rotationally fixed to the output shaft and a driving member having a second plurality of teeth. The first and second pluralities of teeth engage each other when a variation in the torsion angle from a mean torsion angle is greater than a predetermined angle. Torque is transferred between the gear and the output shaft via the clutch when the first and second pluralities of teeth engage each other.

Abstract: An aircraft propeller drive system has a gear to be driven by an engine and having a first plurality of teeth. A torsion bar has a first end driven by the gear and a second end rotatable relative to the first end about a torsion axis by a torsion angle. An output shaft is driven by the second end and is adapted for connection to a propeller. A clutch has a driven member rotationally fixed to the output shaft and a driving member having a second plurality of teeth. The first and second pluralities of teeth engage each other when a variation in the torsion angle from a mean torsion angle is greater than a predetermined angle. Torque is transferred between the gear and the output shaft via the clutch when the first and second pluralities of teeth engage each other.

Abstract: An aircraft propeller drive system has a gear to be driven by an engine and having a first plurality of teeth. A torsion bar has a first end driven by the gear and a second end rotatable relative to the first end about a torsion axis by a torsion angle. An output shaft is driven by the second end and is adapted for connection to a propeller. A clutch has a driven member rotationally fixed to the output shaft and a driving member having a second plurality of teeth. The first and second pluralities of teeth engage each other when a variation in the torsion angle from a mean torsion angle is greater than a predetermined angle. Torque is transferred between the gear and the output shaft via the clutch when the first and second pluralities of teeth engage each other.

Abstract: An aircraft propeller drive system has a gear to be driven by an engine and having a first plurality of teeth. A torsion bar has a first end driven by the gear and a second end rotatable relative to the first end about a torsion axis by a torsion angle. An output shaft is driven by the second end and is adapted for connection to a propeller. A clutch has a driven member rotationally fixed to the output shaft and a driving member having a second plurality of teeth. The first and second pluralities of teeth engage each other when a variation in the torsion angle from a mean torsion angle is greater than a predetermined angle. Torque is transferred between the gear and the output shaft via the clutch when the first and second pluralities of teeth engage each other.

Abstract: A propulsion assembly for propelling an aircraft is disclosed. The assembly includes a four stroke internal combustion engine, a propeller shaft that is operatively connected to the engine, and an electronic control unit that is connected to the engine and is configured to monitor and control at least one operating parameter of the engine. The engine includes two to twelve cylinders having a total displacement of less than 19.6 liters, and a crankshaft that is operatively connected to the cylinders. The crankshaft rotates at a speed of at least 3,000 rpm when the engine is operating under normal conditions. The engine also includes a closed loop liquid cooling system and a fuel injection system. The engine has a total power output of 140 to 600 hp, and a total wet installed weight of less than 1.1 kg/hp. The engine meets current RTCA DO-160d, RTCA DO-178b, and US FAA FAR33 guidelines.

Abstract: A propulsion assembly for propelling an aircraft is disclosed. The assembly includes a four stroke internal combustion engine, a propeller shaft that is operatively connected to the engine, and an electronic control unit that is connected to the engine and is configured to monitor and control at least one operating parameter of the engine. The engine includes two to twelve cylinders having a total displacement of less than 19.6 liters, and a crankshaft that is operatively connected to the cylinders. The crankshaft rotates at a speed of at least 3,000 rpm when the engine is operating under normal conditions. The engine also includes a closed loop liquid cooling system and a fuel injection system. The engine has a total power output of 140 to 600 hp, and a total wet installed weight of less than 1.1 kg/hp. The engine meets current RTCA DO-160d, RTCA DO-178b, and US FAA FAR33 guidelines.

Abstract: A pop-off valve that, in one embodiment, provides overboost protection for an aircraft engine, is described. The pop-off valve includes a housing adapted for connection to a portion of a drive device containing a pressure medium. It also includes a pressure body movably disposed in the housing such that, in operation, a first side of the pressure body is exposed to the pressure medium while a second side is exposed to a reference force. In addition, the pop-off valve incorporates a control device adapted to receive at least one signal concerning at least one operating parameter of the drive device and, in response to the operating parameter signal, to control the reference force. As a result of movement of the pressure body within the housing, at least one first opening in the housing is exposed, permitting venting of the pressure medium.

Abstract: An aircraft control system includes a propeller governor in which a motor is used to apply a compression force on a speeder spring, and a turbocharger in which a motor is used to actuate a needle valve associated with a diaphragm cell. An electronic control unit may be used to control the motor in the propeller governor and the motor in the turbocharger. The integration of the propeller governor and the turbocharger into a single control system decreases the number of individual adjustments that must be performed manually by the pilot.

Abstract: An aircraft control system includes a propeller governor in which a stepper motor is used to apply a compression force on a speeder spring, and a turbocharger in which a stepper motor is used to actuate a needle valve associated with a diaphragm cell. An electronic control unit may be used to control the stepper motor in the propeller governor and the stepper motor in the turbocharger. The integration of the propeller governor and the turbocharger into a single control system decreases the number of individual adjustments that must be performed manually by the pilot.

Abstract: A propulsion assembly for propelling an aircraft is disclosed. The assembly includes a four stroke internal combustion engine, a propeller shaft that is operatively connected to the engine, and an electronic control unit that is connected to the engine and is configured to monitor and control at least one operating parameter of the engine. The engine includes two to twelve cylinders having a total displacement of less than 19.6 liters, and a crankshaft that is operatively connected to the cylinders. The crankshaft rotates at a speed of at least 3,000 rpm when the engine is operating under normal conditions. The engine also includes a closed loop liquid cooling system and a fuel injection system. The engine has a total power output of 140 to 600 hp, and a total wet installed weight of less than 1.1 kg/hp. The engine meets current RTCA DO-160d, RTCA DO-178b, and US FAA FAR33 guidelines.

Abstract: An internal combustion engine for an aircraft is described. The internal combustion engine includes a crankshaft defining first and second ends, a propeller, and a transmission disposed between the first end of the crankshaft and the propeller, operatively connecting the propeller to the crankshaft. A torsion bar is disposed between the first end of the crankshaft and the transmission, operatively connecting the crankshaft to the transmission. A torsional vibration damper is operatively connected at one of the first and the second ends of the crankshaft.

Abstract: A pop-off valve that, in one embodiment, provides overboost protection for an aircraft engine, is described. The pop-off valve includes a housing adapted for connection to a portion of a drive device containing a pressure medium. It also includes a pressure body movably disposed in the housing such that, in operation, a first side of the pressure body is exposed to the pressure medium while a second side is exposed to a reference force. In addition, the pop-off valve incorporates a control device adapted to receive at least one signal concerning at least one operating parameter of the drive device and, in response to the operating parameter signal, to control the reference force. As a result of movement of the pressure body within the housing, at least one first opening in the housing is exposed, permitting venting of the pressure medium.

Abstract: An aircraft control system includes a propeller governor in which a stepper motor is used to apply a compression force on a speeder spring, and a turbocharger in which a stepper motor is used to actuate a needle valve associated with a diaphragm cell. An electronic control unit may be used to control the stepper motor in the propeller governor and the stepper motor in the turbocharger. The integration of the propeller governor and the turbocharger into a single control system decreases the number of individual adjustments that must be performed manually by the pilot.

Abstract: An aircraft control system includes a propeller governor in which a stepper motor is used to apply a compression force on a speeder spring, and a turbocharger in which a stepper motor is used to actuate a needle valve associated with a diaphragm cell. An electronic control unit may be used to control the stepper motor in the propeller governor and the stepper motor in the turbocharger. The integration of the propeller governor and the turbocharger into a single control system decreases the number of individual adjustments that must be performed manually by the pilot.

Abstract: An internal combustion engine for an aircraft is described. The internal combustion engine includes a crankshaft defining first and second ends, a propeller, and a transmission disposed between the first end of the crankshaft and the propeller, operatively connecting the propeller to the crankshaft. A torsion bar is disposed between the first end of the crankshaft and the transmission, operatively connecting the crankshaft to the transmission. A torsional vibration damper is operatively connected at one of the first and the second ends of the crankshaft.

Abstract: An aircraft control system includes a propeller governor in which a stepper motor is used to apply a compression force on a speeder spring, and a turbocharger in which a stepper motor is used to actuate a needle valve associated with a diaphragm cell. An electronic control unit may be used to control the stepper motor in the propeller governor and the stepper motor in the turbocharger. The integration of the propeller governor and the turbocharger into a single control system decreases the number of individual adjustments that must be performed manually by the pilot.