The Wright Stuff

Lilienthal in 1891 designed and flew what was considered by many to be the first successful glider. Refining his design - the basis of modern hang gliders - through a series of gliders, he made more than 2,000 flights over five years. He died August 10, 1896, from injuries suffered when one of them crashed. But his writings, and news of his efforts, piqued the interest of two men in Dayton, Ohio; indeed, Lilienthal's successes - and failures - provided tremendous inspiration to Orville and Wilbur Wright.

Years of effort culminated at 10:35 on the morning of December 17, 1903, when Orville lay prone on the original Wright Flyer, as a 27-mph wind blew sand into his face. The four-cylinder, 12-horsepower engine running properly, Orville released the wire holding the Flyer to its launching track and began moving forward - and upward. "The course of the flight up and down was exceedingly erratic partly due to the irregularity of the air, and partly to the lack of experience in handling this machine," he later wrote. "A sudden dart when a little over 120 feet from the point at which it rose into the air - ended the flight." The flight lasted only 12 seconds, but those 12 seconds marked the first successful flight of a powered, heavier-than-air craft, and defined the following century.

Two sons of Milton Wright, a bishop in the Church of the United Brethren in Christ, and his wife Susan, Orville and Wilbur - at ages 9 and 13, respectively - were fascinated when their father returned from a trip with a toy flying machine constructed of bamboo, cork, and paper, and powered by rubber bands. Employing mechanical abilities they likely picked up from their mother, they built versions of their own. Later, in 1888, Wilbur helped Orville in his efforts to design a printing press. Orville became a successful printer and newspaper publisher; after their mother died in 1889, Wilbur became one of his editors.

A few years later, new commercial presses had increased competition for printing - and the modern bicycle was beginning to show up in the United States. Orville bought one for $160 in 1892; both brothers became excellent riders, and Orville raced. By the end of that year the Wrights had opened a business selling and repairing bicycles, then began to design their own. They spent the cold, snowy Dayton winters improving their designs.

Meanwhile, Lilienthal's hang gliding in Germany intrigued Wilbur. As he nursed Orville through a bout with typhoid fever, they discussed the gliding accident that led to Lilienthal's death in 1896. By 1899 the Wrights were researching the existing information about flight. Many early experimenters had focused on flapping wings, like a bird's. The brothers quickly recognized the limitations of Lilienthal's weight-shift method of control, and the stability benefits provided by wing dihedral, used in aircraft designs today. Obtaining stable control became their focus.

A horizontal stabilizer, which the Wrights called a horizontal rudder, placed in front of the main wings as a canard to control pitch, became a fixture of their designs. Wilbur conceived the idea of helical twisting of the wings, better known as wing warping, to control roll; the concept later matured into today's ailerons. (The Wrights are credited with the concept of three axes of flight, but it wasn't until 1902 that they added a vertical rudder to control yaw - interconnected with wing warping, it did not require separate control inputs from the pilot.)

The Wrights built a kite to validate their wing-warping idea, which was inspired by watching a hawk fly through turbulent air, and began the process of teaching themselves to fly. The next year they built a biplane glider with warping wings and flew it at Kitty Hawk, North Carolina - chosen because of its consistent winds, open space, and soft sand.

Kitty Hawk is on North Carolina's Outer Banks - a string of barrier islands separating the Albemarle Sound from the Atlantic Ocean. A wonderful summer vacation destination today, travel to the islands was difficult in the early 1900s, and the autumn winds were accompanied by falling temperatures. When the Wrights returned in 1901 with a larger glider, they set up camp a few miles away at Kill Devil Hills and built a simple structure. But they were extremely disappointed with the performance of the 1901 glider - it didn't seem to produce enough lift, and the forward-mounted elevator didn't adequately control pitch.

Returning to Dayton, the brothers finally concluded that Lilienthal's data, on which they had based many of their calculations, were incorrect. They built a wind tunnel, which greatly increased their understanding of how a wing works. The effort resulted in the 1902 glider, flown first as a kite before making hundreds of successful manned glides from Kill Devil Hill.

Realizing that a propeller was simply a wing traveling in a spiral course, the Wrights spent the summer of 1903 designing propellers and building the Flyer. So confident were they in the aircraft's performance that in March 1903, nine months before the first powered flight, the Wrights applied for a patent on their work. It was crated and shipped from Dayton to Kill Devil Hills in September, but problems with the propeller shafts caused delays in the first flight. Finally, on December 14, the aircraft was ready - but because winds were light, the launching track was laid on the 9-degree slope of Big Kill Devil Hill. Wilbur took off, climbed a few feet, stalled, and landed 3.5 seconds later near the foot of the hill, causing minor damage. Repairs were completed late on December 16, and the next day dawned cold and windy. When 10 a.m. arrived and the wind had not calmed, they decided to attempt a flight. It was Orville's turn, and his 12-second flight landed in the history books.

Wilbur flew next, also staying up 12 seconds, but going 175 feet. On his second flight Orville traveled 200 feet in 15 seconds. By noon Wilbur had flown again, covering 852 feet in 59 seconds. The Flyer's pitch control was overly sensitive, but the Wrights had accomplished their goal. Then a sudden wind gust tumbled the Flyer, destroying the aircraft.

The brothers continued their efforts, however, and considered the third Wright Flyer built, in 1905, to be the first practical airplane. The size of the elevator was increased, and it was moved farther ahead of the wings. In addition, the rudder was disconnected from the wing-warping mechanism, providing the pilot with independent control around all three axes. Ironically, it was not until flight demonstrations by the Wrights in 1908 that the world really could appreciate their accomplishments.

Both brothers recognized that they were pioneer pilots, as well as inventors. "If you are looking for perfect safety, you will do well to sit on a fence and watch the birds; but if you really wish to learn, you must mount a machine and become acquainted with its tricks by actual trial," Wilbur said, later observing, "Carelessness and overconfidence are usually more dangerous than deliberately accepted risks." In a 1901 address he said, "Practice is the key to the secret of flying."

Three axes of control. Efficient propellers. Gliders that could be considered the first flight-training devices. What other legacies did the Wrights leave?

They used two propellers to act against a greater amount of air, and because "having the propellers turn in opposite directions, the gyroscopic action of one would neutralize that of the other," Orville wrote. Counterrotating propellers, with the descending blade closer to the fuselage's centerline, became popular on multiengine aircraft after World War II because they improve safety if one engine fails - but the Wrights introduced the concept at the birth of powered flight.

And now, 100 years later, wing warping - physical deflection of wing surfaces - is in the spotlight again. In a project sponsored by NASA, the Air Force, and Boeing, an F/A-18A jet fighter modified with warping wings made its first flight in November 2002. Called the active aeroelastic wing, it is designed to enhance aircraft performance by using lighter-weight flexible wings. Additional actuators and thinner wing skins will allow the outer wing panels to twist up to 5 degrees. Engineers hope to see similar roll performance with smaller control surface deflection when compared to production F-18s.

The legacy of every powered airplane flying today goes back to the original Wright Flyer, which two bicycle mechanics from Ohio first flew in gusting winds of up to nearly 30 mph - because they wanted to. Think about that the next blustery day you're at the airport, watching the windsock dance and trying to decide whether you want to go up - in an aircraft much more stable, powerful, and comfortable than anything the Wrights ever built.

Mike Collins is editor of AOPA Flight Training.