Going batty: secrets behind upside-down flight landings revealed

It is an aerial manoeuvre far beyond the capabilities of even the most sophisticated modern aircraft: landing upside down on a ceiling. But it is routine business for bats, and now scientists have learned precisely how they do it. Researchers using high-speed cameras taking images at 1,000 frames per second to observe bats in a special flight enclosure said these flying mammals exploit the extra mass of their wings, which are heavy for their body size compared to those of birds and insects, in order to perform the upside-down landing.

People have many opportunities to observe birds and insects flying, but the bat world is hidden in the night.

Sharon Swartz, Brown University professor

The Brown University team found that by flapping both wings while folding one of them just a bit toward their body, a bat can shift its centre of mass to perform a midair flip in order to alight on a ceiling. When approaching their touchdown spot, bats are not flying very quickly, making it difficult to muster the type of aerodynamic forces generated by pushing against the air that could help position them for an upside-down landing. But their heavy wings enable them instead to generate inertial forces to reorient themselves in midair.

Bats employ this specific manoeuvre every time they land, because for a bat, landing requires reorienting from head forward, back up, belly down, to head down, toes up.

Brown University biology and engineering professor Sharon Swartz

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