Читать книгу The Story of American Aviation - Jim Ray - Страница 9
THE DREAM FULFILLED
ОглавлениеOut in Dayton, Ohio, there were two small brothers, who dreamed, as countless other children before them had dreamed, of flying like birds through the air. Their dreams were heightened by a small toy given to them by their father, the pastor of a local church. This toy was to lead to an idea which had a profound effect on the world. You would probably call it a flying propeller. It consisted of a wooden propeller which slipped over a notched stick. By placing a finger against the propeller and rapidly pushing it up the notched stick, the propeller was made to whirl up off the end of the stick and fly into the air. The brothers, young as they were, never quite forgot this little toy as they continued to dream of flying like birds through the air.
Though the brothers continued to dream of flying, they were not the kind of lads who spent all their time in dreaming. They made kites which flew a little better and a little higher than those made by the other boys in the neighborhood. They built a press to print their own little newspaper, and they dabbled in woodcuts. To carve out porch posts for their father’s home they built an eight-foot wood-turning lathe. Indeed, they were the sort of boys who caused the neighbors to say, “What will they think of next?”
Small town pastors in the early 1890’s did not receive princely salaries. The brothers knew that if they ever wanted to see their dreams come true they must earn their own capital. In the early nineties America was in the midst of the bicycle craze. Everyone who could possibly afford to do so owned a bicycle of some sort and belonged to a cycle club. Being mechanically minded, the brothers did the logical thing. They set themselves up in a small bicycle shop in Dayton, next door to their home.
The bicycle shop in Dayton prospered, for the brothers were careful and expert mechanics, and cyclists in need of repairs made their way to the Wright Brothers’ shop.
The two boys who had never forgotten the little toy helicopter which their father had given them years before, were Orville and Wilbur Wright. Although their bicycle shop prospered the brothers continued to dream of flying. Unlike others, who, all over the world, had been dreaming of the same thing, the dreams of the Wright Brothers persisted. They read everything that had been written about experiments in flying. Every spare moment of their time was spent in thinking about flight.
Soon after Octave Chanute’s book Progress of Flying Machines was published in 1894, Orville and Wilbur Wright read a copy. Although they had long discussed the idea of flight, it was not until they read Chanute’s book that they were able to consider seriously any experiments of their own.
Chanute’s book did not give the answers to the questions in the minds of the Wright Brothers. It was primarily a record of man’s attempts to fly and of his failures. However, it served its purpose because it created many more questions in the minds of Orville and Wilbur Wright. They wrote to Chanute for further information on what man had to do in order to fly.
The noted scientist answered the questions of the Wright Brothers as best he could and sent them a set of tables derived from his studies of air pressure in relation to wing surfaces. The Wrights saw in these figures a possible clue to the mysteries of flight, and in 1900 they built an experimental glider based on the information they had received from Chanute. What followed this first glider experiment is the key to the problem of why the Wright Brothers eventually succeeded while other men failed. When the glider they constructed on the principle of the then most perfect data failed to fly, they were capable of realizing that the scientific research—and not their own efforts—had been at fault.
The Wright Brothers were not only inspired mechanics (as many people still believe today) but serious scientists, working along the soundest lines. In their keen desire to know what air pressure on wings really was, they cleared a corner of their bicycle shop and built a small wind tunnel with spare lumber and an old electric fan. They built small wing sections of various shapes and experimented with them in their wind tunnel. The electric fan was used to create the moving air around the wing section. By attaching the wing sections to a supporting frame and connecting the frame with a pointer and dial, they were able to keep a record of the effect of moving air on each experimental wing section. Through their wind tunnel research the Wright Brothers discovered the four forces that control all heavier-than-air flight: lift, thrust, weight, and drag. They found that a slight curve or camber in the wing section would cause the moving air to travel farther over the top of the wing surface than along the under side. This made the air pressure greater under the wing, gave a suction effect above the wing, and caused it to rise, creating lift. They discovered that a wing section of the proper camber would counteract the weight of gravity. Thus, a wing must be so designed that, with a certain amount of air flowing around it, it would lift a certain weight. They also discovered that air flow against any surface attached to the wing would cause a resistance or drag. Hundreds of experiments in their wind tunnel with various types of wing shapes gave the Wrights a series of tables from which to design a wing that would create the lift for a designed weight.