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When published aeronautical data turned out to be unreliable, the Wright brothers built their own wind tunnel to test airfoils and measure empirically how to lift a flying machine into the sky. They were the first to discover that a long, narrow wing shape was the ideal architecture of flight. They figured out how to move the vehicle freely, not just across land, but up and down on a cushion of air. They built a forward elevator to control the pitch of their craft as it nosed up and down. They fashioned a pair of twin rudders in back to control its tendency to yaw from side to side. They devised a pulley system that warped the shape of the wings in midflight to turn the plane and to stop it from rolling laterally in air. Recognizing that a propeller isn't like a ship's screw, but becomes, in effect, a rotating wing, they used the data from their wind-tunnel experiments to design the first effective airplane props--a pair of 8-ft. propellers, carved out of laminated spruce, that turned in opposite directions to offset the twisting effect on the machine's structure. And when they discovered that a lightweight gas-powered engine did not exist, they decided to design and build their own. It produced 12 horsepower and weighed only 152 lbs.
The genius of Leonardo da Vinci imagined a flying machine, but it took the methodical application of science by these two American bicycle mechanics to create it. The unmanned gliders spawned by their first efforts flew erratically and were at the mercy of any strong gust of wind. But with help from their wind tunnel, the brothers amassed more data on wing design than anyone before them, compiling tables of computations that are still valid today. And with guidance from this scientific study, they developed the powered 1903 Flyer, a skeletal flying machine of spruce, ash and muslin, with a wingspan of 40 ft. and an unmanned weight of just over 600 lbs.
On Dec. 17, 1903, with Orville at the controls, the Flyer lifted off shakily from Kitty Hawk and flew 120 ft.--little more than half the wingspan of a Boeing 747-400. That 12-sec. flight changed the world, lifting it to new heights of freedom and giving mankind access to places it had never before dreamed of reaching. Although the Wright brothers' feat was to transform life in the 20th century, the next day only four newspapers in the U.S. carried news of their achievement--news that was widely dismissed as exaggerated.
The Wright brothers gave us a tool, but it was up to individuals and nations to put it to use, and use it we have. The airplane revolutionized both peace and war. It brought families together: once, when a child or other close relatives left the old country for America, family and friends mourned for someone they would never see again. Today, the grandchild of that immigrant can return again and again across a vast ocean in just half a turn of the clock. But the airplane also helped tear families apart, by making international warfare an effortless reality.