A hawk moth can fly fast, slow, up, down, sideways, even backward. It can hover. It can easily position itself at an open flower swaying in the breeze. Its entire life is an aerial show. Human engineers would love to make a tiny flying device, a little robot insect, if you will, with even a fraction of the flying prowess of a hawk moth, a hummingbird, a bat or a fruit fly.

“Flying animals are ridiculously manoeuverable and stable in flight compared to our own small craft,” says Tyson Hedrick, a biologist at the University of North Carolina.

Until now, no one fully understood how these creatures—which evolved independently of one another—manage to fly so well. They flap their wings, sure enough. But how do they manage such feats of airmanship?

The simple question of how creatures fly is gradually succumbing to the probing of science. A study, led by Hedrick and published last week in the journal Science, has deconstructed one basic flying manoeuver—a turning motion—and discovered that multiple creatures seem to employ the same principle. It may be a universal principle of animal flight, independently derived by countless species over millions of years.

The scientists call it “flapping counter-torque,” or FCT.

A mystery of flight is how animals keep from getting discombobulated and ankles-over-elbows as they swoosh around and interact with their environment. For example, scientists wanted to know how flying animals regain stability—or “arrest the yaw”—after initiating a turn.

The answer turned out to be surprisingly simple. First, the animal initiates the turn with asymmetrical flapping. Then, rather than stopping the turn with a reverse asymmetrical flapping, the animal switches to regular symmetrical flapping. At that point, natural aerodynamics kick in.

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