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Hail Prevention Device
Hail in the French Alps is as common as flies around a manure pile, so it's not surprising that what's billed as "the world's first sure-fire cure for hail damage" should come from there. Farmers who have had to accept a certain amount of hail damage nearly every year are excited about the prospect of damage-free crops.
"They've tried everything from anti-hail rockets to cloud seeding to putting nets over crops. But this is the first and only method that really works. We've proved that in 12 years of testing," Fred 0llivier, of Marseille, France, inventor of the new hail-stopper, told FARM SHOW. He guarantees 100% hail-free coverage over 180 acres in a circle 1 kilometer (.6 of a mile) across.
The new device sends shock waves created by acetylene gas explosions into hail-producing thunderheads. Even in heavy wind and rain, 0llivier and the farmers who've tested the system for years, say nothing more than soggy flakes ever falls in the protected area.
"It's like creating a wave on a freezing pond. Because of the agitation, ice won't form until a much lower temperature is reached," explains 0llivier, adding that the system has to be started at least 20 to 30 min. before the hail clouds themselves appear. That's to let the shock wave pattern build and expand as the system sets off eight wave-producing explosions per minute. "It's like dropping a rock into a pond. If you keep dropping rocks into the same spot the ripples will grow and expand into waves that reach farther and farther from the point of origin."
Here's how it works:
The exploder consists of two parts: A 4 1/2 ft. high cylindrical-shaped explosion chamber, and a 15 ft. mixing cone above it that emits the sound wave. Gas is injected into the base chamber and ignited electronically, blasting out all the air in the upper cone. The entire exploder is anchored to a cement slab.
Gas flow and ignition is controlled by a small computer set-up that's powered either by standard on-line electric power, or by a solar-charged 12-V battery.
"The unit can be turned on with aremote transmission from up to 3 miles away. When you see a possible hail storm developing, you simply turn the system on until the danger is past. We also have an automatic switch-on system that turns on the device whenever it rains, but that can be wasteful since most rains are not hail carriers," says 0llivier.
The entire system is housed in a small building to protect the electronics, with the firing cone sticking out the top.
0llivier notes that some neighbors of operating units claim the device changes rainfall patterns or sends hail to neighboring areas, but he feels there's no evidence that the system does anything other than force hail to fall as water. Noise is a problem, particularly for farmers located near town. One farmer says it's "about as loud as a motorcycle from 1,000 ft. away." The explosions have been measured at 92 decibels.
The device causes no damage to animals, and airplanes have intentionally flown through the shock waves with no noticeable bad effects. 0llivier says he can provide a number of signed testimonials from satisfied farmer-customers of his new anti-hail device, plus a list of 30 to 40 users whom anyone interested can contact directly.  .
The system sells in France for about $27,000, not including the building.
For more information, contact: FARM SHOW Followup, Fred 0llivier, Ste. Corballan, S.A., 5 Place de Rome, Marseille, 13006 France.


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1981 - Volume #5, Issue #3