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Weather Balloons as Wireless Telephone Technology
Under the plan described in this article submitted by reader RoscoHead, "Space Data would use un-tethered weather balloons launched daily by the National Weather Service to carry lightweight wireless communications equipment to an altitude of 100,000 feet. There, at the 'SkySite,' they would relay voice and data signals to remote areas at a fraction of the cost of installing cell towers or launching satellites, company officials say."
Clearly using free-floating weather balloons has a number of limitations and disadvantages.
Now we know that NASA has great plans for its solar-powered airplane -- including acting as a semi-permanent flying repeater-station, but I wonder if smaller, cheaper options might not be available.
For example... what about a much smaller (say 20-30 foot span) autonomous craft designed to soar thermals during the day (while charging its batteries and gaining as much altitude as it can) -- then revert to battery power and/or gradually descend during the hours of darkness.
If the energy required to keep these craft airborn in the longer nights of winter was greater than that availble to be stored during the day then they could carry a fuel-load to power a high-efficiency internal combustion engine (probably a very small diesel engine). Every week or so the craft would have to land for refueling and maintenance -- but that's not a big deal.
Just like the US military's Predator RPV, they could be programmed to land on a runway set aside specially for the purpose.
The cost of a smaller craft, particularly one that wasn't totally reliant on solar-cells, would likely be much less than NASA's efforts -- thus allowing more of them to be built for a given budget.
By using more craft, they could cruise at a much lower altititude than either the weather balloon or the NASA craft.
Using modern composites, low cost GPS, and other "affordable" technologies, such a craft could likely be built for less than US$10K.
Assuming a 50% duty cycle, a fleet of 10 craft could cover a huge area at a much lower cost than towers, and with the ability to dynamically vary the coverage area if required -- simply by repositioning the craft.
I have worked as balloon operator at the Danish Meteorological Institute, so I can tell you how this works: The winds at higher altitudes (10km+) is rather violent, often forcing the balloon to travel 100-200 kilometers eastwards (west is the prevailing direction of the wind in Denmark) during its ascent to an altitude of 30-35km. Then, at the top, the balloon tears (at that time it has expanded to a volume of 100 cubic metres from a starting volume of 1½ cubic meter) and drops gently to the ground, the torn balloon acting as a parachute. The kit is use-and-throw-away, so there is no need to chase the descending balloons (a good thing, because 90% of the balloons I launched landed somewhere in the Baltic Sea).
78% of all statistics are made up on the spot.
I was wondering that, so I looked it up. It turns out that after reaching a certain height, the weather balloon explodes from (internal pressure) and drops its payload. Usually this is a "radiosonde", a device which radios the weather conditions back to the weather station. The radiosonde weights about .3kg and is usually packaged in styrofoam to cushion the landing. Sometimes it has a parachute too.
Inside the radiosonde package there is also a self-addressed prepaid envelope so anyone who finds it can mail it back to the weather service. No kidding!