Abstract: An exemplary passive oil system includes a reservoir housing configured in operation to rotate around a rotational axis, the reservoir housing defining a reservoir between a top wall, a bottom wall, innermost side, and an outer sidewall; and an outlet positioned adjacent the outer sidewall to discharge a lubrication fluid contained in the reservoir in response to the reservoir housing rotating around the rotational axis.

Abstract: Generally described, one or more aspects of the present application correspond to techniques for automatic recovery from dual isolation in which both the primary and secondary replicas of a volume are stored on isolating servers. The disclosed techniques use handshakes between the client and the replicas to determine which has a better health score. The replica with the better health score becomes the primary replica, and confirms that it and the secondary replica are both in an isolating state. In response, the primary replica seeks a solo blessing, undoes the isolating state at the volume level (the server host will still be in isolating state), and continues handling I/O and peer replication until its healthy peer is complete. These techniques can avoid availability drops when the servers hosting the primary and secondary replicas of a volume enter the isolating state at around the same time.

Abstract: A first block storage server virtual machine to host a first volume using one or more storage devices of a computer system is executed by the computer system. A second virtual machine having access to a virtual block storage device is executed by the computer system. A block storage client is executed by the computer system. A first block storage operation is received by the block storage client from the second virtual machine, the first block storage operation to perform on the virtual block storage device. A message is sent by the block storage client to the first block storage server virtual machine to cause the first block storage server virtual machine to perform the block storage operation with the first volume.

Abstract: A first request to create a first storage volume to store a first portion of a first logical volume is received by a first block storage server instance. A second request to create a second storage volume to store a second portion of the first logical volume is received by a second block storage server instance. A third request is sent to a third block storage server instance to create a third storage volume to store the second portion of the first logical volume. The second portion of the first logical volume is stored by the third block storage server instance to the third storage volume. A data store containing an identification of each block storage server instance hosting a portion of the first logical volume is updated to remove an identification of the second block storage server instance and add an identification of the third block storage server instance.

Abstract: A first request to launch a first virtual machine to host a block storage server application is received. At least a portion of a storage capacity of one or more storage devices of a host computer system is provisioned to the first virtual machine as a provisioned storage device. The block storage server application is executed with the first virtual machine. As part of executing the block storage server application, a logical volume is created on the provisioned storage device in response to a second request from a block storage service of a provider network to create the logical volume, a third request to perform an input/output operation is received and performed with the logical volume.

Abstract: A multimode clutch assembly is positioned in a powertrain of a rotorcraft. The clutch assembly includes a freewheeling unit having a driving mode in which torque applied to the input race is transferred to the output race and an overrunning mode in which torque applied to the output race is not transferred to the input race. A bypass assembly has an engaged position that couples the input and output races of the freewheeling unit. An actuator assembly shifts the bypass assembly between engaged and disengaged positions. An engagement status sensor is configured to determine the engagement status of the bypass assembly. In the disengaged position, the overrunning mode of the freewheeling unit is enabled such that the clutch assembly is configured for unidirectional torque transfer. In the engaged position, the overrunning mode of the freewheeling unit is disabled such that the clutch assembly is configured for bidirectional torque transfer.

Abstract: A failsafe multimode clutch assembly is positioned in a powertrain of a rotorcraft. The clutch assembly includes a freewheeling unit having input and output races. The freewheeling unit has a driving mode in which torque applied to the input race is transferred to the output race and an overrunning mode in which torque applied to the output race is not transferred to the input race. A bypass assembly has an engaged position that couples the input and output races of the freewheeling unit. An actuator assembly must be energized to shift the bypass assembly from the engaged position to a disengaged position. In the disengaged position, the overrunning mode of the freewheeling unit is enabled such that the clutch assembly is configured for unidirectional torque transfer. In the engaged position, the overrunning mode of the freewheeling unit is disabled such that the clutch assembly is configured for bidirectional torque transfer.

Abstract: A failsafe multimode clutch assembly is positioned in a powertrain of a rotorcraft. The clutch assembly includes a freewheeling unit having input and output races. The freewheeling unit has a driving mode in which torque applied to the input race is transferred to the output race and an overrunning mode in which torque applied to the output race is not transferred to the input race. A bypass assembly has an engaged position that couples the input and output races of the freewheeling unit. An actuator assembly must be energized to shift the bypass assembly from the engaged position to a disengaged position. In the disengaged position, the overrunning mode of the freewheeling unit is enabled such that the clutch assembly is configured for unidirectional torque transfer. In the engaged position, the overrunning mode of the freewheeling unit is disabled such that the clutch assembly is configured for bidirectional torque transfer.

Abstract: Generally described, one or more aspects of the present application correspond to techniques for creating multiple encrypted block store volumes of data from an unencrypted source. These encryption techniques can use a transform fleet as an intermediary use between the unencrypted source and the encrypted volumes. The transform fleet can obtain data of the volume from one or both of two sources—an object storage “snapshot” a block storage “source volume”—and can then apply the appropriate encryption key for performing the encryption of a particular volume.

Abstract: Notice of migration of a portion of a data volume from a first location to a second location is received by a first computer system from a second computer system, where the data volume is separated over a network from the first computer system. A third computer system, separated over a network from the first computer system, is caused to invalidate a mapping between the portion and the first location. An indication that the third computer system seeks access to the portion is identified. A third computer system is enabled, by providing a mapping between the portion and the second location, to access portion at the second location.

Abstract: Server computers often include one or more input/output (I/O) devices for communicating with a network or directly attached storage device. The data transfer latency for request can be reduced by utilizing ingress data placement logic to bypass the processor of the I/O device. For example, host memory descriptors can be stored in a memory of the I/O device to facilitate placement of the requested data.

Abstract: An exemplary tiltrotor aircraft with a hybrid drive system includes a first propulsion system having a first engine and a first supplemental driver operably coupled to a first proprotor that is operable between a helicopter mode and an airplane mode and a second propulsion system having a second engine and a second supplemental driver operably coupled to a second proprotor that is operable between a helicopter mode and an airplane mode.

Abstract: A first block storage server virtual machine to host a first volume using one or more storage devices of a computer system is executed by the computer system. A second virtual machine having access to a virtual block storage device is executed by the computer system. A block storage client is executed by the computer system. A first block storage operation is received by the block storage client from the second virtual machine, the first block storage operation to perform on the virtual block storage device. A message is sent by the block storage client to the first block storage server virtual machine to cause the first block storage server virtual machine to perform the block storage operation with the first volume.

Abstract: A first request to launch a first virtual machine to host a block storage server application is received. At least a portion of a storage capacity of one or more storage devices of a host computer system is provisioned to the first virtual machine as a provisioned storage device. The block storage server application is executed with the first virtual machine. As part of executing the block storage server application, a logical volume is created on the provisioned storage device in response to a second request from a block storage service of a provider network to create the logical volume, a third request to perform an input/output operation is received and performed with the logical volume.

Abstract: A first request to create a first storage volume to store a first portion of a first logical volume is received by a first block storage server instance. A second request to create a second storage volume to store a second portion of the first logical volume is received by a second block storage server instance. A third request is sent to a third block storage server instance to create a third storage volume to store the second portion of the first logical volume. The second portion of the first logical volume is stored by the third block storage server instance to the third storage volume. A data store containing an identification of each block storage server instance hosting a portion of the first logical volume is updated to remove an identification of the second block storage server instance and add an identification of the third block storage server instance.

Abstract: Generally described, one or more aspects of the present application correspond to techniques for modifying volume encryption status, either by creating an encrypted copy of an unencrypted source volume or by re-encrypting the replica with a different key than the source volume. This can be accomplished using an intermediary transform fleet that stores the encryption key(s) and performs encryption (and decryption, in cases where the source is encrypted). Further, these techniques can implement a state refresh for any client attached to the volume in order to equip the client to handle the different encryption state of the encrypted volume.

Abstract: First information about regions of storage space in a storage environment available for a volume is provided to a service provider, with the storage environment being external to the service provider. The service provider is notified that information usable to locate a storage destination of a portion of the volume is unavailable. Second information that includes the storage destination in the storage environment is obtained from the service provider. A data operation is performed at the storage destination, with the storage destination determined based at least in part from the second information.

Abstract: Systems and methods include providing an aircraft with a fuselage and a wing assembly rotatable relative to the fuselage about a stow axis between a flight position and a stowed position. The aircraft includes a gearbox having a retractable driveshaft that selectively engages the mid-wing gearbox via axially translatable motion along a rotation axis when the wing assembly is in the flight position. The retractable driveshaft also selectively disengages the mid-wing gearbox in the flight position to allow selectively rotation of the wing assembly about the stow axis from the flight position to the stowed position resulting in the mid-wing gearbox being misaligned with the retractable driveshaft when the wing assembly is in the stowed position.

Abstract: A multimode clutch assembly is positioned in a powertrain of a rotorcraft. The multimode clutch assembly includes a freewheeling unit having input and output races. The freewheeling unit has a driving mode in which torque applied to the input race is transferred to the output race and an overrunning mode in which torque applied to the output race is not transferred to the input race. A bypass assembly has an engaged position that couples the input and output races of the freewheeling unit. A hydraulic actuator shifts the bypass assembly between the engaged position and a disengaged position. In the disengaged position, the overrunning mode of the freewheeling unit is enabled such that the multimode clutch assembly is configured for unidirectional torque transfer. In the engaged position, the overrunning mode of the freewheeling unit is disabled such that the multimode clutch assembly is configured for bidirectional torque transfer.

Abstract: A selectable clutch assembly for a multimode powertrain of a rotorcraft. The selectable clutch assembly includes a freewheeling unit having input and output sides. The freewheeling unit has a driving mode wherein torque applied to the input side is transferred to the output side and an over running mode wherein torque applied to the output side is not transferred to the input side. A bypass assembly is coupled to and rotatable with the output side of the freewheeling unit and is actuatable between engaged and disengaged positions with the input side of the freewheeling unit. In the disengaged position, the freewheeling unit is operable in the driving and the over running modes such that the selectable clutch assembly is configured for unidirectional torque transfer. In the engaged position, the over running mode of the freewheeling unit is disabled such that the selectable clutch assembly is configured for bidirectional torque transfer.