Do Flying Squirrels Really Fly?
Flying squirrels are a tribe of 50 species of squirrel in the family Sciuridae. Actually, they can’t fly like birds and bats do, but are gliders. They fly from tree to tree with the aid of a pantagium, a furry parachute-like membrane flap of loose skin that goes from wrist to ankle. This fold catches the air as the squirrel falls, letting it propel itself instead of plummeting. Typically, flying squirrels fly about 15 to 20 feet in their neighborhood, but have been known to fly from 150 or more feet to a destination. Their glide angle approximates 27 degrees with a glide ratio of 1:98. They steer and control their flight with both their limbs and tail.
This ability to glide gives them an advantage for foraging and evading predators. Instead of having to climb up and down trees, which they can do, the can launch and fly away to find food or when being chased. By gliding at high speed, flying squirrels can cover a lot more forest area than a ground squirrel.
People have been watching flying squirrels for some time and have wanted to emulate what they do. Base jumpers (parachuting or wingsuit flying from a fixed structure like a: building, antenna, bridge span, or mountain cliff) and sky divers have developed a suit that mimics the flying squirrel. The suit works to slow descent and allows them to maneuver in the air.
Bernie, the main character in the flying squirrel story, flies into a tree when he is distracted and crashes, landing him in the animal hospital. To keep flying until he recovers, his mother sews him a flexible wing which he uses to great effect, much like hang gliders use.