CAN you remember the first time you saw an airplane streak across the blue sky? You probably can't. You've probably seen so many kinds of aircraft - jets, helicopters, and even space shuttles - that it's hard to imagine a time when humans couldn't circle the earth or visit the moon in flying machines.
In December of 1903, however, when Wilbur and Orville Wright announced that they had flown the world's first engine-powered machine over the beaches of Kitty Hawk, N.C., few people believed them. Humans will fly, people laughed, when the law of gravity is repealed. The New York Times had speculated just two months earlier that a flying machine would be invented someday ... but only if mathematicians and engineers worked for the next one to 10 million years.
The Wright brothers were neither mathematicians nor engineers. They were bicycle mechanics from Dayton, Ohio, who had been interested in flying since they were children.
It all began in 1877 when Wilbur was 11 and Orville was 7. That year their father, Milton Wright, brought them a gift from one of his business trips. It was a small helicopter made of bamboo paddles and rubber bands. The brothers called it "the bat," and played with it until it broke. Then they took it apart and built endless copies of it. Eventually they moved on to other toys, but they never forgot the flying machine.
A few years later another invention, the bicycle, captured their imagination. In the 1890s bicycles with two equal-sized wheels and air-filled tires were new and popular. Wilbur and Orville became avid cyclists. Then they opened a bicycle-repair shop. Business flourished, and soon they were producing and selling bicycles of their own.
In the winter of 1899, when cold weather brought the end of bicycle season, the brothers resumed their interest in flying machines. After reading everything he could find, Wilbur concluded that many of the problems of flight had been solved. Scientists already knew that the most effective wing shape was something like a long teardrop turned on its side. Experiments had shown that air flowing around such a shape created an upward push, called "lift."
Wilbur also knew that the question of how to power a flying machine was nearly answered: He could borrow ideas from the motors being developed for automobiles. That left the question of control. How could someone control a machine when it was moving through the air?
In the air, a vehicle can roll over into a sideways spin. If a gust of wind lifts the tail too high, the nose can pitch downward into a nose dive. And a crosswind can send the machine twirling around its axis like a top.
How did birds deal with these problems? The Wright brothers noticed that when a bird wanted to turn, it twisted the top of one wing upward and dipped the lower edge of the other wing downward. Leaning into the downward wing, the bird could make a perfectly controlled banking turn. But how could the brothers get an aircraft with rigid wooden-frame wings to twist like that?
Wilbur Wright found the answer in an empty inner-tube box. Standing in his shop one day, he fiddled absent-mindedly with the long narrow box, twisting the ends in opposite directions, forward and back, back and forward. Suddenly, as he looked down at his hands, he understood how to twist the wings of an aircraft.
To test his idea, the Wright brothers built a kite with double wings that could be twisted from the ground through a mechanism of sticks and cords. The kite was a spectacular success, as they could easily manipulate it to turn and swoop and dive.
Next they built a glider, large enough to carry a person, using the same principles of control that they had used in their kite. Since gliders are powered only by the wind, the Wright brothers needed to find a windy place to test the aircraft.
Kitty Hawk, N.C., a tiny fishing village on the Atlantic Ocean, was the perfect location. It was windy all year round, there were few people to get in the way, and there was lots of soft sand for sudden landings. The Wright brothers shipped their glider in pieces to Kitty Hawk in September 1900, and they followed by train, traveling three days from Dayton.
For two months the brothers tested their glider. Their control system worked perfectly. Encouraged, they returned to their bicycle shop in Dayton and spent the winter building a larger glider. This time they added something called an "elevator" (a horizontal front rudder), which helped to lift or lower the front of the glider.
The brothers returned to Kitty Hawk the following July. This time their tests were frustrating. The glider often spun completely out of control. And one day it whirled into a damaging crash, leaving Wilbur bruised and cut. Discouraged to the point of giving up, the brothers returned to Dayton. On their way home, Wilbur told Orville he didn't think "man would fly in a thousand years."
Back in their bicycle shop, the brothers went over their research. They began to question the calculations they had found in books. What if the numbers were incorrect? Then they decided to go back to the very beginning: the shape of the wing.
They spent the winter of 1902 building and testing model wings of every configuration. With meticulous attention to detail, they gradually collected new information, and from it they gained new understanding. Small changes to the wing design could make big changes in the aircraft's ability to fly.
The Wrights began building a new glider that looked more like a modern airplane. It had a narrow 32-foot wingspan, and this time the brothers added a tail. They took it to Kitty Hawk the following summer for testing. The glider exceeded all their hopes: It flew almost perfectly.
"Our new machine is a very great improvement over anything we had built before and over anything anyone has built," Wilbur wrote in a letter to his father.
But there was one problem. Every once in a while, when they tried to level off after a turn, the glider spun out of control. The tail had been added to help balance the aircraft during turns, and most of the time it did. But occasionally it didn't. Why?
After a spinning crash one day, Orville discovered the problem. Until then, the tail had been fixed rigidly in place. Sometimes, Orville reasoned, the tail needed to change positions. The brothers modified the tail so that it could be moved by the pilot. This time the glider flew perfectly.
When they left Kitty Hawk that summer, they were ready to design an aircraft with an engine.
From their research they knew their engine would have to be lightweight and produce a lot of power. Orville and a friend began building one in the bicycle shop. (It weighed 750 pounds with the pilot.) Next came propellers. After lengthy study, the Wright brothers constructed propellers that were different from any previous designs.
THAT fall they took their new flying machine, named the Wright Flyer after one of their bicycle models, to Kitty Hawk. On Dec. 14, 1903, they were ready for a test flight, but the wind was not strong enough. They decided to try a downhill launch.
Confident that the test would make history, the brothers flipped a coin to decide who would fly the craft. Wilbur won. He lay down in the pilot's position on the lower wing. The Flyer shot down the hill, then lifted briefly into the air. Wilbur tried to pull the machine up, but he pulled too hard. The machine stalled, fell backward, and crashed into the sand. It took two days to repair the damage to the left wing.
On Thursday, Dec. 17, they decided to try again. This time they would launch from flat ground. It was Orville's turn at the controls. He shook hands with Wilbur and slid into position. The engine coughed and clanked. The propellers clattered. Slowly the machine moved down the beach. The Flyer was heading into a freezing 27-mile-per-hour wind. Wilbur ran alongside, holding a wing to balance the flyer.
After 40 feet, Wilbur let go. Orville lifted up on the controls. The Wright Flyer was in the air! At 30 m.p.h., it flew only 120 feet and remained in the air for 12 seconds before nosing back into the sand.
But the Wright brothers knew they had succeeded. They were the first people in history to fly an engine-powered machine.
They took turns making three more test flights that day. The longest was 852 feet in 59 seconds. Then a sudden gust of wind rolled the Flyer over on the beach and damaged it. That was the end of the flights at Kitty Hawk.
The Wright brothers returned to Dayton and continued to test and improve their aircraft. They received patents for many parts of their invention, and in 1909 they formed an airplane-manufacturing company.
By the time Wilbur died in 1912 at the age of 45, the Wright brothers were famous throughout the world as inventors of the airplane. Orville lived until 1948, long enough to see almost all human endeavor changed by his invention.
Had he lived just 21 years longer, Orville would have witnessed the dawn of the space age: In 1969 the first human to walk on the moon, American astronaut Neil Armstrong, carried with him a piece of the cloth that had once covered the wings of the Wright Flyer. `Kidspace' is a place on The Home Forum pages where kids can find stories that will spark imaginations, entertain with a tall tale, explain how things work, or describe a real-life event. These articles appear twice a month, usually on Tuesdays.