Scientists, as the Telegraph points out, have long been mystified by the bumblebee. It’s short and fat with stubby wings that, mathematically speaking, should never be able to generate enough lift to get the little guy off the ground. And yet it flies. Well, now we might know why:
The underlying problem turned out to be treating a wing as if it was fixed, like in an aeroplane and, thanks to studies over the past few years, including the construction of robotic bees, this “bumble-bee paradox” has been solved: extra lift comes when flexible insect wings slice through the air at a high angle of attack, creating a large swirling vortex at their leading edge.
In this way, insect wings produce the vortices – spinning masses of air – which generate lift and help them move. Today, Prof Ismet Gursul of the University of Bath will describe another step on the way for engineers to make air vehicles smaller than a human hand that can be used for detecting chemicals leaks and reconnaissance.
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The Bath engineers found that a wing which is rigid at the front but more flexible and bendy at the rear is the most efficient way for a small wing to generate optimum vortices and to move in air.