Abstract: A rotor-hub-flap anisotropic-sensor system includes a rotor hub, a plurality of anisotropic-sensor arrangements interoperably coupled to the rotor hub and operable to measure flapping of the rotor hub, a plurality of rotor blades connected to the rotor hub, and at least one flight control computer interoperably coupled to the plurality of anisotropic-sensor arrangements.

Abstract: A lockout system for an aircraft having a rotor assembly. The lockout system includes a drive shaft coupled to and rotatable with the rotor assembly, a nonrotating airframe structure disposed proximate the drive shaft and a lock assembly having first and second lock members. The first lock member is rotatable with the drive shaft and includes a plurality of bearing assemblies. The second lock member is coupled to the nonrotating airframe structure and includes a cradle having a plurality of asymmetric slots each with a leading ramp and a trailing stop. The lock assembly has a disengaged position in which rotation of the drive shaft is allowed and an engaged position in which each of the bearing assemblies is seated within one of the asymmetric slots to prevent rotation of the drive shaft. The lock assembly is actuatable between the engaged and disengaged positions.

Abstract: A lockout system for an aircraft having a rotor assembly. The lockout system includes a drive shaft coupled to and rotatable with the rotor assembly, a nonrotating airframe structure disposed proximate the drive shaft and a lock assembly having first and second lock members. The first lock member is rotatable with the drive shaft and includes a plurality of bearing assemblies. The second lock member is coupled to the nonrotating airframe structure and includes a cradle having a plurality of asymmetric slots each with a leading ramp and a trailing stop. The lock assembly has a disengaged position in which rotation of the drive shaft is allowed and an engaged position in which each of the bearing assemblies is seated within one of the asymmetric slots to prevent rotation of the drive shaft. The lock assembly is actuatable between the engaged and disengaged positions.

Abstract: A rotor-hub-flap anisotropic-sensor system includes a rotor hub, a plurality of anisotropic-sensor arrangements interoperably coupled to the rotor hub and operable to measure flapping of the rotor hub, a plurality of rotor blades connected to the rotor hub, and at least one flight control computer interoperably coupled to the plurality of anisotropic-sensor arrangements.

Abstract: A rotor-hub flap-measurement system includes a rotor hub operable to flap relative to a main-rotor axis, a flap-linkage arm, a first end of the flap-linkage arm rotatably coupled to the rotor hub, the flap-linkage arm responsive to flapping of the rotor hub, and a magneto-resistive sensor system rotatably coupled to a second end of the flap-linkage arm and responsive to movement of the flap-linkage arm.

Abstract: A rotor-regulation system includes a rotor that includes a plurality of rotor blades, a rotor mast operable to drive the rotor, and a rotor disc-brake system operable to modulate rotation of the rotor mast.

Abstract: Embodiments are directed to a blade lock comprising a fold lock adapted to prevent folding of a rotor blade in a fold-lock position and to allow folding of the rotor blade in a pitch-lock position. The blade lock further comprises a pitch lock adapted to allow pitch movement of a rotor blade in a fold-lock position and to prevent pitch movement of the rotor blade in the pitch-lock position. A spring-loaded link pivotally connects both the fold lock and the pitch lock and is adapted to provide passive, overcenter locking in the fold-lock position. An actuator is coupled to the pitch lock and is adapted to move the pitch lock and the fold lock between the fold-lock and pitch-lock positions.

Abstract: A rotor-regulation system includes a rotor comprising a plurality of blades, a mechanically driven hydraulic pump, a rotor drive shaft operable to drive the rotor and the mechanically driven hydraulic pump, and a throttling valve coupled to the mechanically driven hydraulic pump and operable to modulate rotation of the rotor.

Abstract: Embodiments are directed to a blade lock comprising a fold lock adapted to prevent folding of a rotor blade in a fold-lock position and to allow folding of the rotor blade in a pitch-lock position. The blade lock further comprises a pitch lock adapted to allow pitch movement of a rotor blade in a fold-lock position and to prevent pitch movement of the rotor blade in the pitch-lock position. A spring-loaded link pivotally connects both the fold lock and the pitch lock and is adapted to provide passive, overcenter locking in the fold-lock position. An actuator is coupled to the pitch lock and is adapted to move the pitch lock and the fold lock between the fold-lock and pitch-lock positions.

Abstract: A system and method for preventing a maximum asymmetric condition between pylon tilt angles due to a degraded pylon in a fly-by-wire tiltrotor aircraft during transitions between airplane mode and helicopter mode includes a conversion system for imparting movement on a right and left pylon. A flight control computer is operatively connected to a set of transducers for measuring pylon angles. The flight control computer is further connected to a set of actuators which are attached to each pylon. The flight control computer receives flight dynamics input from the set of transducers and/or the pilot and sends pylon command to the set of actuators. The conversion system measures the difference between the pylon angles during the transition and provides a pylon command adjustment if the difference exceeds a preset threshold.

Abstract: Systems and methods include providing an aircraft with a direct drive dual-concentric valve (D3V) having a body, an outer secondary spool coaxially located within a bore of the body and linearly displaceable relative to the body, an inner primary spool coaxially located within a bore of the secondary spool and linearly displaceable relative to the secondary spool and the body. A plurality of piezo stacks is coupled to a first end of the primary spool, and applying a voltage to at least one of the piezo stacks causes an output stroke of the plurality of the piezo strokes for displacing the primary spool. The secondary spool is displaced together with the primary spool relative to the body if displacement of the primary spool relative to the secondary spool cannot occur.

Abstract: A method and system to measure a parameter associated with a component, device, or system with a specified accuracy, including: providing one or more sensors operably disposed to detect the parameter; obtaining a coarse measurement of the parameter within a first range using the one or more sensors, wherein the first range includes minimum and maximum values for the parameter; obtaining a fine measurement of the parameter within a second range using the one or more sensors, wherein the second range is smaller than the first range and has a specified ratio to the first range that provides the specified accuracy; determining a current value of the parameter by combining the coarse and fine measurements; and providing the current value of the parameter to a communications interface, a storage device, a display, a control panel, a processor, a programmable logic controller, or an external device.

Abstract: Embodiments are directed to a blade lock comprising a fold lock adapted to prevent folding of a rotor blade in a fold-lock position and to allow folding of the rotor blade in a pitch-lock position. The blade lock further comprises a pitch lock adapted to allow pitch movement of a rotor blade in a fold-lock position and to prevent pitch movement of the rotor blade in the pitch-lock position. A spring-loaded link pivotally connects both the fold lock and the pitch lock and is adapted to provide passive, overcenter locking in the fold-lock position. An actuator is coupled to the pitch lock and is adapted to move the pitch lock and the fold lock between the fold-lock and pitch-lock positions.

Abstract: A system and method for preventing a maximum asymmetric condition between pylon tilt angles due to a degraded pylon in a fly-by-wire tiltrotor aircraft during transitions between airplane mode and helicopter mode includes a conversion system for imparting movement on a right and left pylon. A flight control computer is operatively connected to a set of transducers for measuring pylon angles. The flight control computer is further connected to a set of actuators which are attached to each pylon. The flight control computer receives flight dynamics input from the set of transducers and/or the pilot and sends pylon command to the set of actuators. The conversion system measures the difference between the pylon angles during the transition and provides a pylon command adjustment if the difference exceeds a preset threshold.

Abstract: A system and method for preventing a maximum asymmetric condition between pylon tilt angles due to a degraded pylon in a fly-by-wire tiltrotor aircraft during transitions between airplane mode and helicopter mode includes a conversion system for imparting movement on a right and left pylon. A flight control computer is operatively connected to a set of transducers for measuring pylon angles. The flight control computer is further connected to a set of actuators which are attached to each pylon. The flight control computer receives flight dynamics input from the set of transducers and/or the pilot and sends pylon command to the set of actuators. The conversion system measures the difference between the pylon angles during the transition and provides a pylon command adjustment if the difference exceeds a preset threshold.

Abstract: A method and system to measure a parameter associated with a component, device, or system with a specified accuracy, including: providing one or more sensors operably disposed to detect the parameter; obtaining a coarse measurement of the parameter within a first range using the one or more sensors, wherein the first range includes minimum and maximum values for the parameter; obtaining a fine measurement of the parameter within a second range using the one or more sensors, wherein the second range is smaller than the first range and has a specified ratio to the first range that provides the specified accuracy; determining a current value of the parameter by combining the coarse and fine measurements; and providing the current value of the parameter to a communications interface, a storage device, a display, a control panel, a processor, a programmable logic controller, or an external device.

Abstract: A method and system to measure a parameter associated with a component, device, or system with a specified accuracy, including: providing one or more sensors operably disposed to detect the parameter; obtaining a coarse measurement of the parameter within a first range using the one or more sensors, wherein the first range includes minimum and maximum values for the parameter; obtaining a fine measurement of the parameter within a second range using the one or more sensors, wherein the second range is smaller than the first range and has a specified ratio to the first range that provides the specified accuracy; determining a current value of the parameter by combining the coarse and fine measurements; and providing the current value of the parameter to a communications interface, a storage device, a display, a control panel, a processor, a programmable logic controller, or an external device.

Abstract: One embodiment is an apparatus including an inner reference tube associated with a load-bearing rotating shaft and having a first set of teeth associated therewith and disposed around a periphery thereof; an outer reference tube associated with an input gear and disposed about the inner reference, the outer reference tube and having a second set of teeth associated therewith and disposed around a periphery thereof wherein teeth comprising the second set of teeth are interleaved with teeth comprising the first set of teeth to comprise an interleaved set of teeth and wherein the inner reference tube and the outer reference tube rotate about a same longitudinal axis and at a same speed as the rotating shaft; and a sensor system comprising a first variable resistance sensor (“VRS”) configured to detect a presence of successive teeth of the interleaved set of teeth and generate an output signal indicative thereof.

Abstract: The aircraft includes a rotor. The rotor includes a plurality of rotor blades. The aircraft further includes a non-rotating aircraft component. A proximity sensor is disposed with at least one of the non-rotating aircraft component and the rotor blades. A flight control computer is electrically coupled to the proximity sensor.

Abstract: The aircraft includes a rotor. The rotor includes a plurality of rotor blades. The aircraft further includes a non-rotating aircraft component. A proximity sensor is disposed with at least one of the non-rotating aircraft component and the rotor blades. A flight control computer is electrically coupled to the proximity sensor.