Weatherwatch: discredited but still popular, enthusiasts keep faith in hail cannon

Mysterious booms shaking the small town of Hammonton in New Jersey in December were traced to a backyard attempt at cloudbusting.

Construction worker Rob Butkowski built a device resembling a giant horn to fire shockwaves into the sky, aiming to prevent hail damaging his vines.

The device mixes acetylene and oxygen and detonates them in an ear-splitting explosion, which the 5-metre horn directs upwards. Technically the device is not an explosive or firearm and is legal if it is operated before 10pm. After that it would be considered a noise nuisance. Butkowski believes it is highly effective.

“You can see the split clouds apart,” he told his local newspaper. “You can hear it rip.”

The hail cannon was invented in 1896 by the Austrian wine grower Albert Stiger. His apparent success at repelling hail from his vineyards led to a rapid proliferation of similar devices, with more than 10,000 in use by 1900.

However, results were inconsistent. The Italian government carried out extensive testing and by 1909 hail cannon were largely discredited. They remain popular with a few enthusiasts and some European vineyards use them despite the lack of meteorological support. Patents are still filed for new versions.

Butkowski says his hail cannon is also a bird-scarer, for which there is better scientific evidence.