Tubular Gore Tetroon

With Gores Deflated

As the balloon climbs, the lift in the gores decreases and the lift in the central cavity takes over.  The gores deflate and both surfaces assume the payload as a double wall normal tetroon.  The tetroon is assembled so that the seal forming the tubing is on the inside surface of the balloon.  A second seal forms the spiral and closes off each end at right angles to each other creating a "Tetroon".  The payload hangs from one corner but is a very small portion of the total aircraft gross weight.

The unit stress on the balloon's skin decreases as the gas expands in climbing to the thinner atmosphere above.  In effect, we will be inflating the balloon on the way up.

Conversely, the hot air balloon between the tetroon and the cabin will have no lift at ceiling and will be re-inflated on the way down and only heated for the final approach and landing.