A photo essay in "McClure's" magazine showing pioneer aviator Otto Lilienthal aloft in his glider inspired the Wright brothers to pursue the elusive goal of human flight.

Photos: (left) National Air and Space Museum, Smithsonian Institution; (right) Library of Congress

Human Air Travel

Two self-taught Midwestern brothers broke the barrier of the air, succeeding where others with government grants and engineering degrees had failed, and shaping the course of the twentieth century.

Bicycle Craze
Wilbur and Orville Wright were inquisitive, adventurous pioneers in the technology of air travel -- but they started out as bicycle mechanics. Growing up in Dayton, Ohio, Wilbur (born in 1867) and Orville (born in 1871) were swept up in a national bicycle craze, opening their own bike shop in 1892. It would become the laboratory for the secretive, modest pair's engineering experiments.

Flight Enthusiasts
Like a small but enthusiastic number of people in the U.S. and Europe, the Wrights believed human flight was possible. They broke the problem down into three elements: wing shape, power source, and control. Others had focused on the first two problems, but the Wrights knew from their bicycle experiences that control was key. From books in their father's library, the brothers schooled themselves on the mechanics of flight. Their "wing warping" mechanism, inspired by watching birds, was a revolutionary breakthrough.

The Wrights' Flying Machine
In 1899, they made their first flying machine -- a kind of kite made of wood, wire, and cloth. The small model succeeded on its test run and the brothers took the next step: human flight. Funding their experiments with the proceeds from their bicycle shop, and after much trial and error, Wilbur and Orville built their "Kitty Hawk Flyer," an instrument that had a lightweight, gas-powered engine and weighed 600 pounds. On December 17, 1903, lifting off from soft North Carolina sand dunes, the "Kitty Hawk" flew 120 feet, far enough to demonstrate that human flight was indeed possible. Almost a year before the test, the brothers had applied for a patent for their invention, which they finally secured in 1906.

Celebrities
Over the next few years, the brothers, who didn't drink or smoke and who refused to fly on Sundays, became international celebrities. Wilbur demonstrated the technology in Europe. Orville test-flew for the U.S. Army. They manufactured their invention and fought patent infringers. Tragically, Wilbur died in 1912 of typhoid fever at the age of 45. Orville sold the company to a business syndicate in 1915 for over $1 million and retired, but continued to publicize his family's contribution to aviation travel until his death in 1948.