With material being delivered from tethered vacuum balloons (such as water for firefighting or powders for cropdusting), the balloon lift need only be great enough to support the structure and material in transit from the ground to the delivery head.
INDICATIONS
By pumping firefighting water from a reservoir or large tank on the ground to a firefighting balloon, delivery could be continued up to the limits of the reservoir.
This is in contrast to conventional water-bombing planes, which take on a water load to the limit of their carrying capacity, discharge it, and return for more.
Development of devices and control software is possible here, with new approaches open to patenting or trade-secreting.
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