Fig24
THE AEROPESKIN AERODYNAMIC RESEARCH FILES:
Paper airplanes accomplish the same thing by bending the back edge of the wing up to fly slower, of down to fly faster. Feathers do not grow all over a bird.

SHADES
SUIT
PADS
HANDLES
ZIPPERS
SHOES
HELMET
SPOILER
AERO
CUPS
IMPORTANT
CHAT ROOM
ROLL TEXT
MAIL
POSTCARD