Water for firefighting could be dumped over a fire-prone or alight area from a tethered or free-moving vacuum balloon.
INDICATIONS
If the vacuum balloon is tethered, the water could be pumped up a hose attached to the tether, so the balloon needs only to support the weight of water in train and pumping could continue to the limits of the local reservoir or supply.
A firefighting balloon could be unmanned and controlled from the ground.
Delivery height, water spread pattern etc are finely variable and could be under control of a computer program using sensors carried on the balloon.
Specialized firefighting vacuum balloons would need special attention to the flammability of their construction materials.
Development of devices and control software is possible here, with new approaches open to patenting or trade-secreting.
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