AMERICA’S SECOND PLANE
In 1909, Glenn H. Curtiss, in a plane of his own design, again won the Scientific American award, by flying 24.7 miles over a closed course. The plane he flew was built on order for the New York Aëronautical Society. This was the first airplane order ever received by an American aircraft manufacturer.
On July 25, 1909, a Frenchman, Louis Bleriot, flew his monoplane twenty-five miles to cross the English Channel. Immediately there was furor in Europe and golden prizes were posted for new airplane developments and designs. The first big air race, the James Gordon Bennett Cup race, was held at Rheims, France, in 1909. Glenn Curtiss flew his machine against the pick of foreign pilots including Bleriot, whom he beat by six seconds to win the Cup. His speed was forty-six miles an hour.
Glenn Curtiss had the benefit of the aëronautical research of the Wright Brothers to aid him in designing his first airplanes, but he could not use the wing warping method of control invented by them. This was thoroughly protected by patents. As a result, Curtiss was forced to work out a new system of lateral controls. He developed the aileron method of control for use in turns or circular flight. He did this by mounting small winglike planes on the rear struts of the plane, between the upper and lower wings. These ailerons were hinged to swing up or down and were attached by cables to a yoke which encircled the pilot’s shoulders. The banking of the plane was produced by the movement of the flier as he leaned against the yoke, pushing it in the direction of the desired bank. Vertical motion was achieved by a fore and aft pressure on the control column by the flier. The wheel on the control column was attached to the vertical rudder by cables. Right or left steering was produced by turning the wheel in the desired direction. To make a climbing turn to the right, the flier would lean against the yoke, pushing to the right. At the same time he would turn his wheel gently to the right and pull the control slightly toward himself. Curtiss’ method of control led the way to the modern type of wing aileron and the general system of control was basically the same as that in use today.
POWER FOR THE AIRPLANE
Going back to the four forces that govern the flight of a plane, we find thrust pulling the plane forward. Thrust is the force that keeps the plane in the air; without it the airplane could not leave the ground for sustained flight. Thrust is created by the propeller. The propeller blades function in the same manner as the wings. Just as the wing of a plane bites into the air to cause lift, the propeller blades, patterned after wing camber, bite into the air to create thrust. Their action on the air is similar to a screw biting its way into wood.
The propeller is whirled by the engine. Without the engine to whirl it the propeller is useless, for without thrust we would have no lift. That makes the engine the governing factor in flight. Weight also is a serious force in flight, and the Wrights and Curtiss found from the beginning that the four-cycle gasoline engine would give greater power for its weight than would a steam or electric engine.
The principle of the airplane engine is the same as the one used in the automobile engine. However, weight always has been a problem to aircraft designers. The automobile engine always has been too heavy for use in a plane. When the Wrights built their first plane, automobile engines weighed 25 to 35 pounds per horsepower. The Wrights built one that weighed 13 pounds per horsepower and produced 12 horsepower. They used this engine in 1903 to power their first plane. Since that time all practical airplanes have been powered with gasoline engines, designed specifically for use in heavier-than-air machines. Since the first flight, engineers constantly have strived to produce engines with greater power and less weight per horsepower. How well they have succeeded is proved by the progress of the airplane.