Abstract: A proprotor system for tiltrotor aircraft having a helicopter mode and an airplane mode. The proprotor system includes a hub and a plurality of proprotor blades coupled to the hub such that each proprotor blade is operable to independently flap relative to the hub and independently change pitch. In the airplane mode, the proprotor blades have a first in-plane frequency greater than 2.0/rev.

Abstract: A yoke for providing a centrifugal force retention load path between a proprotor blade and a hub of a soft-in-plane proprotor system operable for use on a tiltrotor aircraft. The yoke includes a continuous loop having a longitudinal axis and first and second longitudinal sections extending between inboard and outboard arcuate sections. A flapping bearing receiving region is disposed at least partially within the inboard arcuate section to an interior of the continuous loop. A centrifugal force bearing receiving region is disposed at least partially within the outboard arcuate section to the interior of the continuous loop. The continuous loop is formed from a composite material having a plurality of double bias material plies and a plurality of unidirectional material plies such that the number of unidirectional material plies is greater than the number of double bias material plies.

Abstract: A soft-in-plane proprotor system for a tiltrotor aircraft having a helicopter mode and an airplane mode. The proprotor system includes a hub, a plurality of proprotor blades and a plurality of loop yokes, each coupling one of the proprotor blades with the hub and each including first and second longitudinal sections extending between inboard and outboard arcuate sections and a bearing assembly disposed between the inboard and outboard arcuate sections of each loop yoke. Each bearing assembly includes a flapping bearing disposed generally within the inboard arcuate section of the respective loop yoke and coupled to the hub, a lead-lag damper coupled to the hub, a centrifugal force bearing disposed generally within the outboard arcuate section of the respective loop yoke and a blade anchor coupled between the lead-lag damper and the centrifugal force bearing. The blade anchor is also coupled to the respective proprotor blade.

Abstract: A proprotor system operable for use on a tiltrotor aircraft having a helicopter flight mode and an airplane flight mode. The proprotor system includes a rotor hub and a plurality of proprotor blades coupled to the rotor hub such that each proprotor blade has three independent degrees of freedom relative to the rotor hub including blade pitch about a pitch change axis, blade flap about a flapping axis and lead-lag about a lead-lag axis. Each of a plurality of spherical bearings couples one of the proprotor blades with the rotor hub. In addition, each of a plurality of lead-lag dampers couples one of the proprotor blades with the rotor hub, wherein each lead-lag damper is aligned with the pitch change axis of the respective proprotor blade, thereby providing pitch independent lead-lag damping.

Abstract: Drainage systems for excess body fluids and associated methods are disclosed herein. A drainage system in accordance with an embodiment of the present technology can include, for example, a drainage catheter, a first reference line, a second reference line, and a pressure sensor assembly. The catheter can include a flexible interface member and an inlet can be placed in fluid communication with a site of excess body fluid within a patient. A first flexible region of the first reference line can be in pressure communication with the flexible interface member, and a second flexible region of the second reference line can be in pressure communication with the surrounding atmosphere. The pressure sensor assembly can be spaced apart from the flexible regions, and measure the pressures of the first and second reference lines. This information can be used to determine the pressure at the site of excess body fluid.

Abstract: A rotor hub assembly for a rotorcraft includes a yoke forming a bearing bore. The yoke has a teetering axis extending through the bearing bore. The rotor hub assembly includes a flapping bearing disposed in the bearing bore. The flapping bearing is operable to regulate teetering of the yoke about the teetering axis. The rotor hub assembly includes an axial spring abutting the flapping, thereby reducing movement of the flapping bearing along the teetering axis.

Abstract: A system for providing secure authentication between a service provider and at least one user device having a storage. The system having a processor managed by the service provider, which processor manages authentication between the at least one device and the service provider. The processor is configured to generate a block including at least user account information upon receipt of an authentication request from the at least one device; apply a cryptographic hash function to the block to create a hashed block; transmit the hashed block to the at least one device for storage in the memory of the at least one device; and upon receipt of the hashed block, validate the hashed block prior to providing access to the service provider.

Abstract: A wing airframe for a wing of a tiltrotor aircraft includes a wing airframe core assembly and a wing skin assembly disposed on the wing airframe core assembly. The wing skin assembly includes an outer skin and a damping sublayer, the damping sublayer interposed between the outer skin and the wing airframe core assembly. The tiltrotor aircraft includes a pylon assembly subject to aeroelastic movement during forward flight. The wing is subject to deflection in response to the aeroelastic movement of the pylon assembly.

Abstract: A proprotor system operable for use on a tiltrotor aircraft having a helicopter flight mode and an airplane flight mode. The proprotor system includes a rotor hub and a plurality of proprotor blades coupled to the rotor hub such that each proprotor blade has three independent degrees of freedom relative to the rotor hub including blade pitch about a pitch change axis, blade flap about a flapping axis and lead-lag about a lead-lag axis. Each of a plurality of spherical bearings couples one of the proprotor blades with the rotor hub. In addition, each of a plurality of lead-lag dampers couples one of the proprotor blades with the rotor hub, wherein each lead-lag damper is aligned with the pitch change axis of the respective proprotor blade, thereby providing pitch independent lead-lag damping.

Abstract: There is described a method for interrogating optical fiber comprising fiber Bragg gratings (“FBGs”), using an optical fiber interrogator. The method comprises (a) generating an initial light pulse from phase coherent light emitted from a light source, wherein the initial light pulse is generated by modulating the intensity of the light; (b) splitting the initial light pulse into a pair of light pulses; (c) causing one of the light pulses to be delayed relative to the other of the light pulses; (d) transmitting the light pulses along the optical fiber; (e) receiving reflections of the light pulses off the FBGs; and (f) determining whether an optical path length between the FBGs has changed from an interference pattern resulting from the reflections of the light pulses.

Abstract: Embodiments are provided for a cooling fan that has a vortex tube, an air turbine, and one or more fan blades. The vortex tube is capable of being supplied with compressed air and splitting the compressed air into a cold stream and a hot stream. The cold stream can spins said air turbine with attached fan blades, causing said fan blades to spin and blow cold air.

Abstract: A yoke for providing a centrifugal force retention load path between a proprotor blade and a hub of a soft-in-plane proprotor system operable for use on a tiltrotor aircraft. The yoke includes a continuous loop having a longitudinal axis and first and second longitudinal sections extending between inboard and outboard arcuate sections. A flapping bearing receiving region is disposed at least partially within the inboard arcuate section to an interior of the continuous loop. A centrifugal force bearing receiving region is disposed at least partially within the outboard arcuate section to the interior of the continuous loop. The continuous loop is formed from a composite material having a plurality of double bias material plies and a plurality of unidirectional material plies such that the number of unidirectional material plies is greater than the number of double bias material plies.

Abstract: A soft-in-plane proprotor system for a tiltrotor aircraft having a helicopter mode and an airplane mode. The proprotor system includes a hub, a plurality of proprotor blades and a plurality of blade support assemblies coupling the proprotor blades with the hub. Each blade support assembly includes a flapping bearing coupled to the hub and a yoke having first and second longitudinal sections with outboard grip members and an inboard arcuate section connecting the first and second longitudinal sections and coupled to the flapping bearing. A lead-lag damper is coupled between the hub and an inboard station of the respective proprotor blade. A twist shank is coupled between the outboard grip members of the yoke and an outboard station of the respective the proprotor blade. The twist shank defines a virtual lead-lag hinge outboard of the yoke and coincident with the respective pitch change axis.

Abstract: A proprotor system for tiltrotor aircraft having a helicopter mode and an airplane mode. The proprotor system includes a hub and a plurality of proprotor blades coupled to the hub such that each proprotor blade is operable to independently flap relative to the hub about a flapping axis and independently change pitch about a pitch change axis. The proprotor blades have a first in-plane frequency less than 1.0/rev.

Abstract: A soft-in-plane proprotor system for a tiltrotor aircraft having a helicopter mode and an airplane mode. The proprotor system includes a hub, a plurality of proprotor blades and a plurality of loop yokes, each coupling one of the proprotor blades with the hub and each including first and second longitudinal sections extending between inboard and outboard arcuate sections and a bearing assembly disposed between the inboard and outboard arcuate sections of each loop yoke. Each bearing assembly includes a flapping bearing disposed generally within the inboard arcuate section of the respective loop yoke and coupled to the hub, a lead-lag damper coupled to the hub, a centrifugal force bearing disposed generally within the outboard arcuate section of the respective loop yoke and a blade anchor coupled between the lead-lag damper and the centrifugal force bearing. The blade anchor is also coupled to the respective proprotor blade.

Abstract: A rotor hub assembly for a rotorcraft includes a yoke forming a bearing bore. The yoke has a teetering axis extending through the bearing bore. The rotor hub assembly includes a flapping bearing disposed in the bearing bore. The flapping bearing is operable to regulate teetering of the yoke about the teetering axis. The rotor hub assembly includes an axial spring abutting the flapping, thereby reducing movement of the flapping bearing along the teetering axis.

Abstract: A proprotor system for tiltrotor aircraft having a helicopter mode and an airplane mode. The proprotor system includes a hub and a plurality of proprotor blades coupled to the hub such that each proprotor blade is operable to independently flap relative to the hub and independently change pitch. In the airplane mode, the proprotor blades have a first in-plane frequency greater than 2.0/rev.

Abstract: A process of remanufacturing a component such as an attachment flange used in turbochargers is provided and includes using a steam oxidation process to form an adhesion layer on top of a sealing surface of the component. The adhesion layer is an oxidation layer that a thermal metal spray coating can be applied on top of in order to prevent spalling that can occur at high heat. Once the process is completed, the component can be inspected to ensure that it meets or exceeds the manufacturer's original specifications.