Why snakes don’t need wings to fly
By ANITuesday, November 23, 2010
WASHINGTON - Scientists have discovered that some species of snake can stay airborne for up to 79 feet.
The acrobatic arboreal snakes, all in the genus Chrysopelea, use what’s known as gliding flight to sail from tree to tree in their Southeast and South Asia habitats.
The research might lead to improved micro-air vehicles, small unmanned and often autonomous flying machines that mimic these actions.
“The snake isn’t defying gravity or doing something out of the blue,” Discovery News quoted project leader Jake Socha, a Virginia Tech biologist, as saying.
“It’s the magnitude of the forces that are somewhat surprising. Given that this is a snake, and its cross-sectional body shape is more like a blunt shape than a typical streamlined wing, we wouldn’t have expected such good aerodynamic performance,” he added.
The team developed a mathematical model and found that the “snake creates lift using a combination of its flattened cross-sectional shape and the angle that it takes to the oncoming airflow, known as the angle of attack.”
To take off from a tree branch, for example, these snakes will drop the front of their bodies to create a “J”-shaped loop before jumping and accelerating upwards. That motion hurls the snake into the air.
But they don’t fall back on the ground immediately. Instead, “the snake is pushed upward-even though it is moving downward-because the upward component of the aerodynamic force is greater than the snake’s weight,” Socha said.
“But our modeling suggests that the effect is only temporary, and eventually the snake hits the ground to end the glide.”
“It’s really remarkable that an animal that, at first glance, possesses a body plan that seems so ill-suited to gliding can not only support its body weight with aerodynamic forces, but actually create a surplus of these forces,” said Greg Byrnes, a postdoctoral fellow in the University of Cincinnati’s Department of Biological Sciences.he study will be published in the journal Bioinspiration and Biomimetics. (ANI)
