Low down sound keeps birds away from planes

摘要

Planes and birds aren't good at sharing air space - bird strikes worldwide cause over a billion dollars in damage every year, and put passengers and crew at risk. To scare avians away, a new device will fire low-frequency sound waves at flocks as they near busy flight paths. Noise makers are often used to scare birds away from airports or contaminated waterways. But loud sounds also annoy any humans within earshot.