Abstract: An example reusable high-altitude balloon system includes a balloon with a first end supporting a payload and a second end with an aperture and an apex fitting that is positioned within the aperture. A clamp applies a pressure to a plurality of pleated folds formed in the perimeter of the aperture around the apex fitting to form an air-tight seal against the balloon at the perimeter of the aperture. The reusable high-altitude balloon system further includes control circuitry that controllably releases the apex fitting from the balloon to initiate a descent sequence.

Abstract: An example reusable high-altitude balloon system includes a balloon with a first end supporting a payload and a second end with an aperture and an apex fitting that is positioned within the aperture. A clamp applies a pressure to a plurality of pleated folds formed in the perimeter of the aperture around the apex fitting to form an air-tight seal against the balloon at the perimeter of the aperture. The reusable high-altitude balloon system further includes control circuitry that controllably releases the apex fitting from the balloon to initiate a descent sequence.

Abstract: An example method for launching a high-altitude balloon includes securing a launch collar around a balloon envelope to form a choke point separating an upper portion of the balloon envelope from a lower portion of the balloon envelope. The balloon envelope is structurally secured to a launch platform via a tether that is coupled to the launch collar. The launch collar is configured such that release of the launch collar from the choke point releases the balloon envelope from the launch platform.

Abstract: An example method for launching a high-altitude balloon includes securing a launch collar around a balloon envelope to form a choke point separating an upper portion of the balloon envelope from a lower portion of the balloon envelope. The balloon envelope is structurally secured to a launch platform via a tether that is coupled to the launch collar. The launch collar is configured such that release of the launch collar from the choke point releases the balloon envelope from the launch platform.

Abstract: An example reusable high-altitude balloon system includes a balloon with a first end supporting a payload and a second end with an aperture and an apex fitting that is positioned within the aperture. A clamp applies a pressure to a plurality of pleated folds formed in the perimeter of the aperture around the apex fitting to form an air-tight seal against the balloon at the perimeter of the aperture. The reusable high-altitude balloon system further includes control circuitry that controllably releases the apex fitting from the balloon to initiate a descent sequence.

Abstract: An example method for launching a high-altitude balloon includes securing a launch collar around a balloon envelope to form a choke point separating an upper portion of the balloon envelope from a lower portion of the balloon envelope. The balloon envelope is structurally secured to a launch platform via a tether that is coupled to the launch collar. The launch collar is configured such that release of the launch collar from the choke point releases the balloon envelope from the launch platform.

Abstract: 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.

Abstract: 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.