Abstract: Provided are flow batteries that include a fluidic train within a dynamic fluidic network system which fluidic train is convertible between a first state and a second state, the first state the first state placing a main electrolyte source and a dynamic fluidic network, outside the fluidic train and an electrode region, into fluid communication with the electrode region and the second state placing the main electrolyte source and the dynamic fluidic network, outside the fluidic train and the electrode region, into fluid isolation from the electrode region and placing the electrode region into fluid communication with a sampling segment. Also provided are methods of operating flow batteries.

Abstract: According to an aspect, an ejector member includes an annular member; a vent arranged at the annular member, the vent having an inlet at a first surface of the annular member, the vent further having an outlet arranged radially inward from a second surface of the annular member; and a vane extending radially inward from the second surface of the annular member.

Abstract: A propeller system for a tail section of an aircraft includes a propeller hub located at the tail section of the aircraft, a plurality of propeller blades mounted to and extending outwardly from the propeller hub, a propeller shaft coupled to the propeller hub and operable to rotate the propeller hub about an axis of rotation, and a propeller gearbox connected to the propeller shaft. The propeller gearbox is fluidly cooled by an airflow within the tail section. A spinner assembly surrounds the propeller hub. The spinner assembly includes at least one outlet opening formed therein downstream from the propeller hub relative to the airflow. The spinner assembly is rotatable to draw the airflow into at least one cooling flow inlet formed in the tail section and across the propeller gearbox to cool the propeller gearbox and out the at least one outlet opening.

Abstract: A rotor blade assembly includes a rotor blade having inboard and outboard regions, a blade body, and an internal spar, the blade body defining leading and trailing edges. A trailing edge assembly extends from and is connected to the trailing edge, and has a trailing edge flap and an actuator configured to deploy the trailing edge flap between first and second positions. In one of the first and second positions, an upper surface of the trailing edge flap conforms in profile to an upper surface of the rotor blade, and in the other, the trailing edge flap is inclined relative to the blade. During hovering flight, at least one trailing edge flap segment is deflected to enhance hover performance. During forward flight, at least one trailing edge flap segment is either not deflected for reduced effect on forward flight or is deflected for additional thrust.

Abstract: A deployment system for a spacecraft may include a fitting for coupling a deployable device to the spacecraft, and a moment bearing shear ball assembly. The moment bearing shear ball assembly may include a shear ball engaged within the fitting, and a moment collar mounted onto the shear ball. The moment collar may have a planar surface engaged with a planar surface of the fitting. A separation interface may be defined between at least one of (1) mating surfaces of the fitting and the shear ball and (2) mating surfaces of the fitting and the moment collar. Engagement of the shear ball within the fitting constrains shear forces in at least two axes and axial forces in at least a third axis. Engagement of the moment collar with the shear ball and the fitting constrains overturning moments of the shear ball about at least two axes, and axial forces in at least a third axis.

Abstract: An aircraft includes an airframe, and a coaxial main rotor assembly including a static mast and an upper rotor assembly and a lower rotor assembly rotatable about a main rotor axis defined by the static mast. The upper rotor assembly and the lower rotor assembly are independently rotatable about the static mast. A propulsion system includes at least one propulsion source for directly driving at least one of the upper rotor assembly and the lower rotor assembly and a flight control system is operably coupled to the propulsion system. The flight control system is operable to independently control a rotational speed of the upper rotor assembly and the lower rotor assembly relative to the static mast.

Abstract: Provided are assemblies, comprising: a first leaf spring; a second leaf spring; and at least one component; the first leaf spring and the second leaf spring being superposed over a first end of the at least one component so as to exert first and second forces, respectively, through first and second regions of the component. These assemblies are useful to apply different forces to a stacked assembly where a cross section of a component of the assembly comprises materials of different Young's moduli within that cross section, thereby compressing different regions of the component with different forces.

Abstract: This disclosure relates to apparatuses, systems, and methods for controlling an aircraft. A computing system may identify a first command signal received via a flight control at a time point to control navigation of the aircraft through an environment. The computing system may attenuate the first command signal using a fade function over a time window relative to the time point to generate a second command signal. The computing system may input the second command signal to a model to generate predicted paths for the aircraft through the environment over the time window. The computing system may determine that at least one predicted path intersects with an obstacle in the environment during the time window. The computing system may generate a location to which to navigate the aircraft to avoid the obstacle. The computing system may perform an action to direct the aircraft to the location.

Abstract: In one embodiment, systems and methods include using a workforce augmenting inspection device (“WAND”) to measure a parameter of an aircraft. The WAND comprises a body, wherein the body comprises one or more buttons configured to actuate the WAND to perform one or more functions. The WAND further comprises a head comprising a camera and a light source, wherein the light source is disposed around the camera operable to produce light in conjunction with operation of the camera, wherein the camera is operable to capture an image within a scope of view of the camera. The WAND further comprises a standoff wheel, wherein the standoff wheel is operable to rotate independently of the head. The WAND further comprises a power source operable to provide power to the WAND, wherein the power source comprises a controller configured to actuate the head, camera, and light source.

Abstract: A rotor blade assembly of an aircraft having a rotor hub including a structural member having an inboard end and an outboard end, the structural member being connectable with the rotor hub. A spar surrounds the structural member and extends at least partially along a rotor blade axis. A pitch bearing assembly supports the spar relative to the structural member. The pitch bearing assembly includes an inboard pitch bearing mounted to the inboard end of the structural member and an outboard pitch bearing mounted to the outboard end of the structural member. The rotor blade assembly additionally includes a centrifugal assembly including a centrifugal bearing disposed between the inboard pitch bearing and the outboard pitch bearing relative to the rotor blade axis.

Abstract: Provided herein are various improvements to laser communication ranging. In one example, a method includes combining a ranging signal with data communications into an optical transmission for receipt by a communication node, and obtaining an additional optical transmission transferred by the communication node comprising additional data communications combined with a retransmitted version of the ranging signal. The method includes determining an indication of a range to the communication node based at least on a comparison between properties of the ranging signal and properties of the retransmitted version of the ranging signal after separation from the additional data communications.

Abstract: Systems and methods for communication in 4G and 5G broadband satellite networks are provided. The disclosed methods include Global Navigation Satellite System (GNSS)-independent methods, and GNSS assisted methods that do not require transmission of satellite ephemeris information from a base station to user equipment.

Abstract: A heat pipe has an evaporator portion, a condenser portion, and at least one flexible portion that is sealingly coupled between the evaporator portion and the condenser portion. The flexible portion has a flexible tube and a flexible separator plate held in place within the flexible tube so as to divide the flexible tube into a gas-phase passage and a liquid-phase artery. The separator plate and flexible tube are configured such that the flexible portion is flexible in a plane that is perpendicular to the separator plate.

Abstract: Provided herein are various examples of separable waveguide couplers. In one example, a collar element is provided to surround a member comprising a faying surface, a waveguide conduit, and alignment protrusions arranged radially about a perimeter of the faying surface, where the collar element is configured to accept insertion of a mating member comprising a mating faying surface and a mating waveguide conduit. A ball detent assembly is provided having a spring element that retains ball elements in holes formed through the collar element. The waveguide conduit and the mating waveguide conduit are configured to be aligned radially by at least engagement of the alignment protrusions with alignment channels in the mating member and restrained axially by at least engagement of the ball elements with mating divots in the mating member.

Abstract: A boresighting mechanism for adjusting an armament of an aircraft. The mechanism includes a housing comprising a proximal end, a distal end, and an inner cavity. The mechanism further includes a jackscrew with a threaded portion disposed in the inner cavity and an unthreaded portion extending from the proximal end of the housing. The mechanism further includes a follower threadedly coupled to the jackscrew at a first end within the inner cavity and extending from the distal end of the housing. The follower is configured to be coupled to an adjustment feature of the armament at a second end. The mechanism further includes an adjustment knob coupled to the unthreaded portion of the jackscrew and configured to rotate the jackscrew to thereby cause linear motion of the follower. The linear motion allows for adjustment of the armament via the adjustment feature.

Abstract: A rotor system including a rotor hub, a plurality of rotor blades supported by the rotor hub, and a fairing mounted to the rotor hub. The fairing includes an external surface exposed to an external airflow and an internal surface defining an interior portion. A component system is mounted to the rotor hub in the interior portion. The component system includes a first heat generating component and a second heat generating component spaced from the first heat generating component. A cooling duct is arranged between the first heat generating component and the second heat generating component.

Abstract: A feed network is provided that includes a transmit section, a body section coupled to the transmit section, and a receive section coupled to the body section. The transmit section and the body section form a transmitter unit coupled to a first section of a core waveguide, wherein the first section of the core waveguide is a square waveguide. The body section and the receive section form a receiver unit coupled to a second section of the core waveguide, wherein the second section of the core waveguide is a circular waveguide.

Abstract: A rotor blade retention assembly is configured to connect a rotor blade to a central hub comprising a hub arm coupled to and extending radially outward from a hub bowl. The hub arm includes a hub arm lug. The rotor blade retention assembly includes a tension-torsion strap with an inboard end and an outboard end, the inboard end including an inboard pin hole and the outboard end including an outboard pin hole. The rotor blade retention assembly further includes an inboard blade pin and an outboard blade pin. The inboard blade pin is configured to extend through the hub arm lug and the inboard pin hole and to couple the inboard end of the tension-torsion strap to the hub arm. The outboard blade pin is configured to extend through a blade lug of a rotor blade and the outboard pin hole and to couple the outboard end of the tension-torsion strap to the rotor blade.

Abstract: According to an aspect, a method of assembling a mandrel includes assembling a plurality of members via interlocking features arranged at opposing edges of each member of the plurality of members to form a compartment, the assembled members having a collective outer surface that conforms to an inner surface of the spar. A support member is inserted into the compartment formed radially inward from the assembled members, the support member making contact with a portion of each member of the plurality of members.

Abstract: A satellite communication system includes a satellite, satellite base station (eNodeB or gNodeB) and a user equipment (UE). The satellite provides a number of satellite beams, and each satellite beam includes multiple cells. The base station communicates with the UE via a satellite using a narrowband internet of things (NB-IoT) waveform and an enhanced protocol. In particular, the base station and UE perform carrier aggregation by adding and/or deleting carriers in a cell, and the base station and UE perform a higher-order modulation and coding scheme (MCS) processing to support high data rates for user data transport.