Bat's Secret of Upside Down Landing Uncovered by Examining Weighty Wings (VIDEO)

First Posted: Nov 17, 2015 10:22 AM EST

Bats may have the heaviest wings comparatively to their body size-but why? Scientists have taken a closer look at bat wings and have found that they're specially designed to allow the mammals to land upside down.

"Bats land in a unique way," said Sharon Swartz, one of the researchers, in a news release. "They have to go from flying with their heads forward to executing an acrobatic maneuver that puts them head down and feet up. No other flying animal lands the same way as bats do."

In order to better understand bat aerodynamics, researchers used a special flight enclosure, high-speed cameras and computer modeling. This revealed that bat landings had a lot to do with wing mass and inertia.

Bat wings are heavy, hand-like assemblages of bone, muscles, joints, tendons and skin. By throwing that extra wing weight around in a very precise manner, bats can generate inertial forces in order to reorient themselves, rather than relying on the aerodynamic forces generated by pushing against the air. This is similar to the way high divers shift their weigh to perform flips and twists.

"What this tells us is that in bats with their heavy wings, it's the inertial forces that are more important relative to aerodynamics," said Kenny Breuer, one of the researchers. "That's a bit of a counterintuitive conclusions. Normally you'd think that an animal would not want to have such massive wings. But here, it turns out that the mass can be used to some benefit."

The findings reveal a bit more about bats, but could also be used in the development of drones.

"From an engineering perspective, there's a lot of interest in drones and flying microvehicles," said Breuer. "Maneuvering or directing those robotic vehicles is a challenge. The idea here is that using redistribution of mass is not a bad approach to take."

The findings are published in the journal PLOS Biology.