and distribute the load. These tapes, which converge to the load ring at the bottom, actually support the load (Figure 6). An open bottom permits the escape of excess lifting gas and thus prevents rupture.
[figure]
Figure 6. Appendix detail, polyethylene balloon.
On the Winzen balloons, which are made from .015" polyethylene, all but two of the balloons were made with similar fiber tape reinforcements; these two were produced without tapes and both of them have been flown with no evidences of unsatisfactory performance.
The eggplant shaped balloon produced by The Goodyear Tire & Rubber Company, Inc. has been flown with satisfaction, but the exact amount of diffusion, which is expected to be low from this balloon, is not yet known.
C. Internal-Pressure Balloons
From a theoretical standpoint the most satisfactory means of keeping a balloon at constant pressure-altitude is to use a non-extensible
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