Controlling lifting gas in inflatable structures

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.

What is claimed is: 
     
         1 . An aircraft comprising:
 an inflatable structure defining a volume;   a nozzle defining an exit, the nozzle in fluid communication with the volume;   an igniter in a vicinity of the exit of the nozzle; and   a payload coupled to the inflatable structure, the payload including a strategic portion and a controller, the strategic portion of the payload at least partially exposed to an environment outside of the volume, and the controller configured to actuate the nozzle to issue a lifting gas from the volume in a direction from the exit toward at least the strategic portion of the payload, and to actuate the igniter to ignite a combustible mixture including the lifting gas directed from the exit of the nozzle.   
     
     
         2 . The aircraft of  claim 1 , wherein the nozzle includes a mixing section in fluid communication with the exit of the nozzle, and the mixing section defines at least one orifice through which air in the environment is movable into the mixing section to mix with the lifting gas from the volume upon actuation of the nozzle. 
     
     
         3 . The aircraft of  claim 1 , wherein the payload further comprises a sensor, and the controller is further configured to receive a signal from the sensor and to actuate at least one of the nozzle or the igniter based on the signal from the sensor. 
     
     
         4 . The aircraft of  claim 3 , wherein the sensor includes one or more of an altimeter, a thermocouple, a timer, or a global positioning system receiver. 
     
     
         5 . The aircraft of  claim 3 , wherein the sensor includes a wireless communication receiver configured to receive a remote signal from a remote source. 
     
     
         6 . The aircraft of  claim 3 , wherein the payload further comprises a transmitter, and the controller is further configured, based on the signal from the sensor, to activate the transmitter to transmit data from the strategic portion of the payload to a remote entity. 
     
     
         7 . The aircraft of  claim 6 , wherein the transmitter is a line-of-sight data transmitter. 
     
     
         8 . The aircraft of  claim 6 , wherein the transmitter is configured for encrypted communication. 
     
     
         9 . The aircraft of  claim 1 , wherein the igniter is a spark igniter. 
     
     
         10 . A controller for controlling an aircraft including an inflatable structure, the controller comprising:
 a processing unit; and   one or more non-transitory computer storage media in electrical communication with the processing unit, the one or more non-transitory computer storage media having stored thereon instructions that, when executed by the processing unit, cause the processing unit to carry out operations including   receiving a signal from a sensor,   based on the signal from the sensor, controlling a flow of a lifting gas from a volume of the inflatable structure through a nozzle directed toward a strategic portion of a payload coupled to the inflatable structure, and based on the signal from the sensor, actuating an igniter to ignite a combustible mixture including the lifting gas moving through the nozzle.   
     
     
         11 . The controller of  claim 10 , wherein the signal from the sensor includes one or more of an altitude, a temperature, a time, or coordinates. 
     
     
         12 . The controller of  claim 10 , wherein the signal from the sensor includes a remote signal from a remote source. 
     
     
         13 . The controller of  claim 10 , wherein the instructions that, when executed by the processing unit, cause the processing unit to carry out controlling the flow of the lifting gas includes actuating a control valve of the nozzle. 
     
     
         14 . The controller of  claim 10 , wherein the one or more non-transitory storage media have further stored thereon instructions that, when executed by the processing unit, cause the processing unit to carry out an operation including activating a transmitter to transmit data from the strategic portion of the payload of the inflatable structure to a remote entity.