Abstract: A rotor system for an aircraft includes an open rotor assembly comprising an open rotor assembly comprising a plurality of rotor blades connected to a rotor mast, wherein the rotor assembly is tiltable relative to a wing of the aircraft between a first position corresponding to an airplane mode of the aircraft and a second position corresponding to a helicopter mode of the aircraft; and a drive system for providing rotational energy to the open rotor assembly via the rotor mast. The drive system includes at least one electric motor for generating rotational energy to a motor shaft; and a gearbox connected to receive rotational energy from the at least one electric motor via the motor shaft and to provide rotational energy to the rotor mast via a rotor shaft, wherein the at least one electric motor is fixed relative to the wing of the aircraft.

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 system for an aircraft includes an open rotor assembly comprising a plurality of rotor blades connected to a rotor mast via a yoke, wherein the rotor assembly is tiltable between a first position corresponding to an airplane mode and a second position corresponding to a helicopter mode; and a drive system for providing rotational energy to the open rotor assembly via the rotor mast, the drive system comprising at least one electric motor for providing rotational energy to a drive shaft and a gearbox connected to the drive shaft for receiving rotational energy from the at least one electric motor via the drive shaft and providing rotational energy to the rotor mast via a rotor shaft; wherein the drive system is rotatable relative to the wing about a tilt axis and the rotor shaft is coaxial with the drive shaft.

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 system for an aircraft includes an open rotor assembly comprising a plurality of rotor blades connected to a rotor mast via a yoke, wherein the rotor assembly is tiltable between a first position corresponding to an airplane mode and a second position corresponding to a helicopter mode; and a drive system for providing rotational energy to the open rotor assembly via the rotor mast, the drive system comprising at least one electric motor for providing rotational energy to a drive shaft and a gearbox connected to the drive shaft for receiving rotational energy from the at least one electric motor via the drive shaft and providing rotational energy to the rotor mast via a rotor shaft; wherein the drive system is rotatable relative to the wing about a tilt axis and the rotor shaft is coaxial with the drive shaft.

Abstract: A resolver assembly for a ducted-rotor aircraft is configured to detect and measure rotation of a spindle of the aircraft. The resolver assembly includes first and second gear-driven resolvers. The first and second resolvers are coupled about a shared pivot axis and are independently pivotable about the pivot axis to maintain engagement of the first and second resolvers with the spindle of the aircraft. The resolver assembly is configured such that the first and second resolvers are biased toward the spindle. The input shafts of the first and second resolvers are spaced from the pivot axis through respective first and second distances that extend outward from the pivot axis along respective first and second radial directions. The first distance is equal to the second distance and the first radial direction is not coincident with the second radial direction.

Abstract: A rotor system for an aircraft is described and includes an open rotor assembly comprising a plurality of rotor blades connected to a rotor mast; and a drive system for providing rotational energy to the open rotor assembly via the rotor mast. The drive system includes at least one electric motor for providing rotational energy to a motor shaft; and a gearbox connected to the drive shaft for receiving rotational energy from the at least one electric motor via the motor shaft and providing rotational energy to the rotor mast via a rotor shaft.

Abstract: An electric motor adapted to apply torque to a drive shaft rotatable about an axis, the electric motor includes a stator, a rotor adapted to rotate relative to the stator, a primary bearing interoperably coupled to the stator and adapted to provide bearing support between the stator and the rotor, an auxiliary bearing interoperably coupled to the drive shaft, an annular shear adapter connected to the primary bearing and the auxiliary bearing, and a shear pin interoperably coupled to the primary bearing via the annular shear adapter and configured to break responsive to torque between the annular shear adapter and the drive shaft exceeding a predetermined torque threshold.

Abstract: An electric motor adapted to apply torque to a drive shaft rotatable about an axis, the electric motor includes a stator, a rotor adapted to rotate relative to the stator, a primary bearing interoperably coupled to the stator and adapted to provide bearing support between the stator and the rotor, an auxiliary bearing interoperably coupled to the drive shaft, an annular shear adapter connected to the primary bearing and the auxiliary bearing, and a shear pin interoperably coupled to the primary bearing via the annular shear adapter and configured to break responsive to torque between the annular shear adapter and the drive shaft exceeding a predetermined torque threshold.

Abstract: A rotor system for an aircraft includes an open rotor assembly comprising an open rotor assembly comprising a plurality of rotor blades connected to a rotor mast, wherein the rotor assembly is tiltable relative to a wing of the aircraft between a first position corresponding to an airplane mode of the aircraft and a second position corresponding to a helicopter mode of the aircraft; and a drive system for providing rotational energy to the open rotor assembly via the rotor mast. The drive system includes at least one electric motor for generating rotational energy to a motor shaft; and a gearbox connected to receive rotational energy from the at least one electric motor via the motor shaft and to provide rotational energy to the rotor mast via a rotor shaft, wherein the at least one electric motor is fixed relative to the wing of the aircraft.

Abstract: A rotor system for an aircraft includes an open rotor assembly comprising a plurality of rotor blades connected to a rotor mast via a yoke, wherein the rotor assembly is tiltable between a first position corresponding to an airplane mode and a second position corresponding to a helicopter mode; and a drive system for providing rotational energy to the open rotor assembly via the rotor mast, the drive system comprising at least one electric motor for providing rotational energy to a drive shaft and a gearbox connected to the drive shaft for receiving rotational energy from the at least one electric motor via the drive shaft and providing rotational energy to the rotor mast via a rotor shaft; wherein the drive system is rotatable relative to the wing about a tilt axis and the rotor shaft is coaxial with the drive shaft.

Abstract: A rotor system for an aircraft is described and includes an open rotor assembly comprising a plurality of rotor blades connected to a rotor mast; and a drive system for providing rotational energy to the open rotor assembly via the rotor mast. The drive system includes at least one electric motor for providing rotational energy to a motor shaft; and a gearbox connected to the drive shaft for receiving rotational energy from the at least one electric motor via the motor shaft and providing rotational energy to the rotor mast via a rotor shaft.

Abstract: A resolver assembly for a ducted-rotor aircraft is configured to detect and measure rotation of a spindle of the aircraft. The resolver assembly includes first and second gear-driven resolvers. The first and second resolvers are coupled about a shared pivot axis and are independently pivotable about the pivot axis to maintain engagement of the first and second resolvers with the spindle of the aircraft. The resolver assembly is configured such that the first and second resolvers are biased toward the spindle. The input shafts of the first and second resolvers are spaced from the pivot axis through respective first and second distances that extend outward from the pivot axis along respective first and second radial directions. The first distance is equal to the second distance and the first radial direction is not coincident with the second radial direction.