Abstract: A system for deploying an inflatable structure may include a balloon defining an envelope having a first stiffness, a valve assembly including a control valve, and a reactor defining a chamber having a second stiffness, the valve assembly disposed in fluid communication between the chamber and the envelope, the control valve selectively actuatable to control fluid communication between the chamber and the envelope, the second stiffness of the chamber greater than the first stiffness of the envelope, and the reactor foldable onto itself along the chamber and elastically deformable to unfold in response to an increase in pressure in the chamber.

Abstract: Devices, systems, and methods are directed to controlling lifting gas in a volume defined by an inflatable structure of an aircraft. For example, controlling lifting gas in the volume of the inflatable structure may account for variations in ambient and tactical conditions experienced by the aircraft over the course of flight, as may be useful for lifting the aircraft to a target altitude and/or carrying out a particular mission. Additionally, or alternatively, controlling lifting gas in the volume of the inflatable structure may facilitate lifting the aircraft using lifting gas generated by reacting stable materials with one another at a launch site in the field. As an example, aluminum may react with water to form a lifting gas including hydrogen and steam. As the steam condenses to water in the inflatable structure, a valve may expel water from the inflatable structure to assist in maintaining buoyancy of the aircraft.

Abstract: According to one aspect, a system for processing material to form activated aluminum, may include a thermal reactor defining a chamber, a support disposed outside of the chamber, a shaft having a first portion and a second portion defining a longitudinal axis, the first portion disposed on the support and the second portion disposed in the chamber, and the shaft rotatable about the longitudinal axis, a fixture supported on the second portion of the shaft in the chamber, and a restraint releasably securable to the second portion of the shaft, the restraint and the fixture spaced relative to one another to hold a plurality of kits of material therebetween as the shaft rotates the fixture, the restraint, and the plurality of kits of material, about the longitudinal axis, in the chamber.

Abstract: A system for hydrogen formation includes a container and at least one object. The container defines a reservoir and is flexible along the reservoir. The container forms a gas-tight seal between the reservoir and an atmosphere outside of the container. The at least one object includes aluminum in an activated form. The at least one object is disposed in an inert environment in the reservoir, and the activated form of the aluminum reactable to produce hydrogen in the reservoir upon exposure to water.

Abstract: According to one aspect, a system for launching an aerostat may include a reactor defining a chamber, an inflatable structure including a balloon and a neck, the balloon and the neck collectively defining a volume, a coupling defining a passage in fluid communication between the chamber of the reactor and the volume of the inflatable structure, the passage defining a longitudinal axis, and a collar supported on the reactor, the collar defining an orifice in fluid communication between the chamber of the reactor and the passage of the coupling, and the collar releasably restricting displacement of the passage of the coupling, the volume of the inflatable structure, and the chamber of the reactor relative to one another along the longitudinal axis.

Abstract: A composite object for the production of hydrogen from water-reactive aluminum may include a first portion including an aluminum alloy having a non-recrystallized grain structure, and a second portion including an activation metal corrodible to the aluminum alloy, wherein the second portion and the first portion are coupled to one another with the activation metal of the second portion in contact with the aluminum alloy of the first portion at a plurality of points of contact stress, and the activation metal of the second portion is penetrable into the non-recrystallized grain structure of the aluminum alloy of the first portion via the addition of heat.

Abstract: According to one aspect, a system for launching an aerostat may include an inflatable structure defining a volume having a neck, a reactor defining a chamber, a coupling releasably secured in fluid communication between the chamber and the neck, and a drain valve within the volume, the drain valve in a first position away from the neck to receive a lifting gas from the chamber into the volume via the coupling, the drain valve movable from the first position to a second position when the coupling is released from fluid communication between the chamber and the neck, and the drain valve in the second position in sealed engagement with the inflatable structure along the neck to control accumulation of condensate from the lifting gas within the volume.

Abstract: According to one aspect, a system for midair deployment of an aerostat may include an inflatable structure including a balloon at least partially defining a volume, a reaction vessel defining a chamber in fluid communication with the volume, a fuel package disposed in the chamber, the fuel package including a container and water-reactive aluminum, the container fluidically isolating the water-reactive aluminum from an environment of the chamber, and an actuator actuatable to release the water-reactive aluminum from the container into the environment of the chamber.

Abstract: According to one aspect, a system for midair deployment of payload may include an aerostat including an inflatable structure, at least one tether, and a trigger, the at least one tether extending between the inflatable structure and the trigger, and at least one unmanned aerial vehicle (UAV) including wings, the at least one tether mechanically coupling the at least one UAV to the inflatable structure, and the trigger actuatable to release mechanical coupling of the at least one tether between the at least one UAV and the inflatable structure in midair.

Abstract: Materials, kits, and methods are directed to controlling reactability of activated aluminum to produce hydrogen when exposed to water. For example, a moisture-stabilized material may be treatable with one or more additives to form a water-reactive source of hydrogen. The moisture-stabilized material may include a bulk volume including aluminum, at least one activation metal disposed along the aluminum within the bulk volume, the at least one activation metal more noble than the aluminum, and a salt along at least an outer surface of the bulk volume, the salt dissolvable in water to form an ion-containing solution at a rate faster than a reaction rate of water with the aluminum of the bulk volume.

Abstract: A system for controlling contamination in hydrogen production from water-reactive aluminum includes at least one reaction vessel. For example, each reaction vessel may include a container, a conduit, and a plurality of baffles. The container may define a volume, and the conduit may define an orifice outside of the container and spaced away from the container. The plurality of baffles may be disposed in the volume to form a tortuous flow path through the volume to the orifice of the conduit to facilitate rapid production of a large quantity of hydrogen from water-reactive aluminum while reducing the likelihood that ejecta, aerosols, or a combination thereof, may escape the reaction vessel to interfere with end-use of the hydrogen produced.

Abstract: According to one aspect, a system for midair deployment of payload may include an aerostat including an inflatable structure, at least one tether, and a trigger, the at least one tether extending between the inflatable structure and the trigger, and at least one unmanned aerial vehicle (UAV) including wings, the at least one tether mechanically coupling the at least one UAV to the inflatable structure, and the trigger actuatable to release mechanical coupling of the at least one tether between the at least one UAV and the inflatable structure in midair.

Abstract: A method of packaging water-reactive aluminum may include directing at least one discrete object into a container, the at least one discrete object including an aluminum alloy, the aluminum alloy plastically deformed and non-recrystallized, introducing, into the container, a liquid metal alloy including one or more activation metals, enclosing the at least one discrete object and the liquid metal alloy with one another in the container to form a kit, for a predetermined period, exposing the kit to a heating environment, and agitating the at least one discrete object and the liquid metal alloy in the container in the heating environment during the predetermined period to form the kit into a packaged unit of water-reactive aluminum.

Abstract: A system for deploying an inflatable structure may include a balloon defining an envelope having a first stiffness, a valve assembly including a control valve, and a reactor defining a chamber having a second stiffness, the valve assembly disposed in fluid communication between the chamber and the envelope, the control valve selectively actuatable to control fluid communication between the chamber and the envelope, the second stiffness of the chamber greater than the first stiffness of the envelope, and the reactor foldable onto itself along the chamber and elastically deformable to unfold in response to an increase in pressure in the chamber.

Abstract: Aluminum can be used as a fuel source when reacted with water if its native surrounding oxide coating is penetrated with a gallium-based eutectic. When discrete aluminum objects are treated in a heated bath of eutectic, the eutectic penetrates the oxide coating. After the aluminum objects are treated, the aluminum objects can be reacted in a reactor to produce hydrogen which can, for example, react with oxygen in a fuel cell to produce electricity, for use in a variety of applications.

Abstract: Aluminum can be used as a fuel source when reacted with water if its native surrounding oxide coating is penetrated with a gallium-based eutectic. When discrete aluminum objects are treated in a heated bath of eutectic, the eutectic penetrates the oxide coating. After the aluminum objects are treated, the aluminum objects can be reacted in a reactor to produce hydrogen which can, for example, react with oxygen in a fuel cell to produce electricity, for use in a variety of applications.

Abstract: Aluminum can be used as a fuel source when reacted with water if its native surrounding oxide coating is penetrated with a gallium-based eutectic. When discrete aluminum objects are treated in a heated bath of eutectic, the eutectic penetrates the oxide coating. After the aluminum objects are treated, the aluminum objects can be reacted in a reactor to produce hydrogen which can, for example, react with oxygen in a fuel cell to produce electricity, for use in a variety of applications.

Abstract: Materials, kits, and methods are directed to controlling reactability of activated aluminum to produce hydrogen when exposed to water. For example, a moisture-stabilized material may be treatable with one or more additives to form a water-reactive source of hydrogen. The moisture-stabilized material may include a bulk volume including aluminum, at least one activation metal disposed along the aluminum within the bulk volume, the at least one activation metal more noble than the aluminum, and a salt along at least an outer surface of the bulk volume, the salt dissolvable in water to form an ion-containing solution at a rate faster than a reaction rate of water with the aluminum of the bulk volume.

Abstract: A system for controlling contamination in hydrogen production from water-reactive aluminum includes at least one reaction vessel. For example, each reaction vessel may include a container, a conduit, and a plurality of baffles. The container may define a volume, and the conduit may define an orifice outside of the container and spaced away from the container. The plurality of baffles may be disposed in the volume to form a tortuous flow path through the volume to the orifice of the conduit to facilitate rapid production of a large quantity of hydrogen from water-reactive aluminum while reducing the likelihood that ejecta, aerosols, or a combination thereof, may escape the reaction vessel to interfere with end-use of the hydrogen produced.

Abstract: A system for deploying an inflatable structure may include a balloon defining an envelope having a first stiffness, a valve assembly including a control valve, and a reactor defining a chamber having a second stiffness, the valve assembly disposed in fluid communication between the chamber and the envelope, the control valve selectively actuatable to control fluid communication between the chamber and the envelope, the second stiffness of the chamber greater than the first stiffness of the envelope, and the reactor foldable onto itself along the chamber and elastically deformable to unfold in response to an increase in pressure in the chamber.