An example reusable high-altitude balloon system includes a control system configured to initiate a termination sequence by separating a payload from an Earth-facing end of the balloon body. Separation of the payload from the balloon body generates a torque that causes the balloon body to invert and release lift gas through a vent duct, initiating a flight termination sequence that facilitates landing of the reusable balloon system without destroying the balloon body.

A method for launch of an airship includes connecting a cargo airship to a second airship that is not positively buoyant at the launch site, launching the cargo airship, transferring lifting gas from the cargo airship to the second airship where said lifting gas is carried by the cargo airship while aloft; and releasing the second airship from the cargo airship. A releasable payload return vehicle, wherein the payload return vehicle generates aerodynamic forces while it is mated to the cargo airship.

A method for launch of an airship includes connecting a cargo airship to a second airship that is not positively buoyant at the launch site, launching the cargo airship, transferring lifting gas from the cargo airship to the second airship where said lifting gas is carried by the cargo airship while aloft; and releasing the second airship from the cargo airship. A releasable payload return vehicle, wherein the payload return vehicle generates aerodynamic forces while it is mated to the cargo airship.

A balloon system, preferably including a balloon and a payload. A balloon, preferably including a plurality of gores, a plurality of load members, and an apex fitting. A method of balloon system operation, preferably including deflating a balloon, and optionally including operating the balloon system in flight and/or landing the balloon system.

A balloon system, preferably including a balloon and a payload. A balloon, preferably including a plurality of gores, a plurality of load members, and an apex fitting. A method of balloon system operation, preferably including deflating a balloon, and optionally including operating the balloon system in flight and/or landing the balloon system.

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.

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.

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.

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.

A fixed housing that is configured to be coupled to a balloon envelope and an impeller housing disposed within the fixed housing, wherein the impeller housing and the fixed housing form a seal in a closed position, wherein the impeller housing is moveable into the balloon envelope relative to the fixed housing in an open position, and wherein the impeller housing defines an unobstructed airflow passageway between an internal chamber in a balloon envelope and the atmosphere in the open position.