The Boy's Book of New Inventions

by Harry E. Maule

Another one of the difficult problems the inventors had to struggle with was the balance of their fliers. Before the Wright brothers flew, it was thought that one of the best ways was to incline the planes upward from the centre—that is—make them in the shape of a gigantic and very broad V. This is known in science as a dihedral angle. The idea was that the centre of gravity, or the point of the machine which is heaviest and which seeks to fall to earth first through the attraction of gravitation, should be placed immediately under the apex of the V. The scientists thought that the V then would keep the machine balanced as the hull of a ship is balanced in the water by the heavy keel at the bottom. The Wrights decided that this might be true from a scientific point of view, but that the dihedral angle kept the machine wobbling, first to one side and then righting itself, and then to the other side and righting itself. This was a practical fault and they built their flier without any attempt to have it right itself, but rather arched the planes from tip to tip as well as from front to rear.

The winglike gliders of Lilienthal and Chanute had been balanced by the shifting of the operator's body, but the Wrights wanted a much bigger and safer machine than either of these pioneers had flown. In their own words, the Wrights "wished to employ some system whereby the operator could vary at will the inclination of different parts of the wings, and thus obtain from the wind forces to restore the balance which the wind itself had disturbed." This they later accomplished by a device for warping or bending their planes, but in their first glider there was no warping device and the horizontal front rudder was the only controlling device used. This latter device on the first glider was made of a smaller plane, oblong-shaped and set parallel to, and in front of, the main planes. It was adjustable through the system of levers fixed for the operator, who in those days lay flat on the front plane.

Thus the two main planes and the adjustable plane in front with stays, struts, etc., made up the first Wright glider.

The Wright brothers took their machine to Kitty Hawk, N. C., in October, 1900, presumably for their vacation. They went there because the Government Weather Bureau told them that the winds blew stronger and steadier there than at any other point in the United States. Also it was lonely enough to suit the Wrights' desire for privacy. It was their plan to fly the contrivance like a boy does a huge box kite, and it looked something like one. A man, however, was to be aboard and operate the levers. According to the Wright brothers' story the winds were not high enough to lift the heavy kite with a man aboard, but it was flown without the operator and the levers worked from the ground by ropes.

A new machine the next year showed little difference of design, but the surface of the planes was greater. Still the flier failed to lift an operator. At this time the Wright brothers were working with Octave Chanute, the Chicago inventor, engineer and scientist whom they had invited to Kitty Hawk to advise them. After many discussions with Chanute they decided that they would learn the laws of aviation by their own experience and lay aside for a time the scientific data on the subject.

They began coasting down the air from the tops of sand dunes, and after the first few glides were able to slide three hundred feet through the air against a wind blowing twenty-seven miles an hour. The reason their glider flights were made against the wind was because the wind passing swiftly under the planes had the same effect as if the machine was moving forward at a good clip, for the faster the machine moves, or the faster the air passes under it, the easier it remains aloft. In other words, no one part of the air was called upon to support the planes for any length of time, but each part supported the planes for a very short time. For instance, if you are skating on thin ice you run much less danger of breaking through if you skate very fast, because no one part of the ice is called upon to support you for long.

In 1902 the Wright brothers were approaching their goal. Slowly and with rare patience they were accumulating and tabulating all the different things different kinds of planes would do under different circumstances. In the fall of that year they made about one thousand gliding flights, several of which carried them six hundred feet or more. Others were made in high winds and showed the inventors that their control devices were all right.

The next year, 1903, which always will be remembered as the banner one in the history of aviation, the brothers, confident that they were about to succeed in their long search for the secret of the birds, continued their soaring or gliding. Several times they remained aloft more than a minute, above one spot, supported by a high, steady wind passing under their planes.

"Little wonder," wrote the Wright brothers a few years, later, "that our unscientific assistant should think the only thing needed to keep it indefinitely in the air would be a coat of feathers to make it light."

What the inventors did to keep their biplane glider in the air indefinitely, however, was to add several hundred pounds to the weight in the shape of a sixteen-horsepower gasoline motor. The total weight of the machine when ready to fly was 750 pounds. Every phase of the problem had been worked out in detail—all the calculations gone over and proved both by figures and by actual test. The planes, rudders, and propellers had been designed by mathematical calculations and practical tests.