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WINGS IN A BICYCLE SHOP

Standing in front of the wrought-iron fence at 1127 West Third Street in Dayton, all you see today is a large, grassy lot that makes a gap in a row of late nineteenth-century commercial buildings. But here is where the airplane was born. It’s the site of the bicycle shop where the Wright brothers made their biggest breakthroughs in unlocking the secrets of flight. The original building, like the Wright family home at 7 Hawthorn, today stands in Henry Ford’s Greenfield Village in Dearborn, Michigan. But its foundation still lies largely intact beneath the surface.¹

This bicycle shop is the only one with a direct connection to the Wright brothers’ airplane work. But if Katharine Wright’s suspicion was correct in 1896, the 22 South Williams shop played an important indirect role.

In late August 1896, Orville fell seriously ill with typhoid fever and was bedridden for more than a month. Antibiotic treatments weren’t available in those days, so there was little to do but keep Orville comfortable, let the disease run its course and hope for the best. Wilbur and Katharine took turns staying by his side and reading to him—as much to pass the time as to entertain Orville, who was delirious through much of September.

On August 9, famous German aviation pioneer Otto Lilienthal crashed while flying his glider, an early version of a hang glider that he controlled by shifting his weight. He died the next day. With nearly two thousand glides in a variety of designs, Lilienthal was a guiding light in aeronautics, and his death was a serious blow to the quest for flight.

The site of the Wright brothers’ bicycle shop at 1127 West Third Street is preserved as a green space in the Wright-Dunbar neighborhood. Author’s photo.

Wilbur and Orville had read about Lilienthal’s work, and years later they both cited his death as the spark that ignited their desire to conquer the air. But exactly how the spark caught isn’t clear. Kelly wrote in The Wright Brothers that both men began researching the problem of flight “after Orville was well enough to hear about Lilienthal’s fatal accident.” Fred Howard was skeptical in his book Wilbur and Orville. “It makes a nice story,” he wrote, but he noted that U.S. papers had reported the accident well before Orville fell ill, so it’s possible they had begun talking about it already.

Crouch’s deep research for The Bishop’s Boys convinced him that Wilbur began thinking seriously about flight years before Orville; he wrote that Wilbur “brought [his brother] up to date about Lilienthal” while Orville was recuperating in October and discussed the accident with him then.

Wilbur’s own words favor Crouch’s version. He later said that news of Lilienthal’s death “aroused a passive interest which had existed from my childhood, and led me to take down from the shelves of our home library a book on Animal Mechanism by Prof. [Etienne Jules] Marey, which I had already read several times. From this I was led to read more modern works.” Orville, he added, “soon became equally interested.” The passage suggests Wilbur may have passed hours at Orville’s bedside reading and thinking about the subject, the passion to unlock the secrets of flight inflaming him as typhoid fever raged in his brother. Wilbur even alluded to his interest as a disease nearly four years later in the beginning of his first letter to Octave Chanute: “For some years I have been afflicted with the belief that flight is possible to man.”

So how does the bicycle shop at 22 South Williams figure in it? Katharine suspected the typhoid germs came from a well at the shop. Milton didn’t doubt it. “Let no one use the well water at the store henceforth,” he wrote in an August 31 letter to Katharine. If they were right, the polluted well at 22 South Williams laid Orville low and bound Wilbur to his bedside for weeks with little to do but contemplate Lilienthal’s death, read and think, incubating the fever for flight that eventually would afflict them both.

In later years, the Wright brothers traced their interest in aviation back to an incident in their childhood when they were living in Cedar Rapids. One evening, the bishop returned home from a trip with a novel gift for the boys: a rubber band–powered toy helicopter that flew into the air and fluttered against the ceiling. The toy fascinated eleven-year-old Wilbur and his seven-year-old brother Orville. “A toy so delicate lasted only a short time in the hands of small boys, but its memory was abiding,” Orville wrote in an article under both brothers’ names for the September 1908 issue of the Century. Wilbur made several versions of the toy, each one larger than the last.

By the close of the nineteenth century, years of spectacular and sometimes tragic failures by Lilienthal and others had convinced most people that flight was impossible. But the trail of failures made Wilbur and Orville all the more curious.

From his observations, Wilbur understood that humans couldn’t match the gymnastic feats of birds darting after insects, but he saw no reason why they couldn’t build machines that would allow them to move through the sky like the vultures he’d watched soaring along the Great Miami River. Had anyone disproved the idea? In 1899, he decided to find out.

“It is only a question of knowledge and skill just as in all acrobatic feats…I believe that simple flight at least is possible to man,” he wrote in a May 30, 1899 letter to the Smithsonian Institution. “I am about to begin a systematic study of the subject in preparation for practical work…I wish to avail myself of all that is already known and then if possible add my mite² to help on the future worker who will attain final success.” Assistant Secretary Richard Rathbun promptly sent Wilbur several pamphlets published by the Smithsonian and a list of other works on aeronautics. Wilbur soaked it all up.

The Wright Brothers Aviation Center at Dayton History’s Carillon Park includes the original Wright Flyer III and a replica bicycle shop (foreground). Author’s photo.

An important pioneer was Sir George Cayley. The English scholar recognized that lift and thrust were separate forces that could be addressed individually, permitting the use of fixed wings and propellers. In 1799, he drew a concept for a flying machine with cambered wings, or wings with curved upper surfaces. It also had a steerable tail that functioned as rudder and elevator, propellers for thrust and a place for a pilot. He was the first to test wing shapes with a whirling arm, the forerunner of the wind tunnel.

Another pioneer was Alphonse Pénaud, a nineteenth-century French marine engineer who pioneered the concept of achieving inherent side-to-side stability in a flying machine with slightly v-shaped, or dihedral, wings and fore-and-aft stability with a horizontal elevator mounted at an angle slightly more positive than the wings. One of his most important contributions was a toy airplane he called the planophore. Its main features included a single cambered wing, a long stick for a fuselage and a tail. It popularized Cayley’s concept and inspired countless young people to think about flight. A design he published in 1875 included such modern features as retractable landing gear, a control stick and a cockpit with a glass enclosure.

Louis Pierre Mouillard of France revisited soaring bird flight in his influential 1881 book L’Empire de l’Air. His own experiments had convinced him of the importance of using gliders to learn control before attempting powered flight.

Otto Lilienthal had a powerful influence on the Wright brothers. Like them, he was a thinker, a craftsman and an athlete. He applied his literary and laboratory research to actual experiments in gliders. Some of his glides exceeded 750 feet, farther than anyone had flown with wings. He left behind the results of his research, including a body of data on wing performance the Wright brothers would use to develop their first gliders. Historians consider his book Der Vogelflug als Grundlage der Fliegekunst (translated as Bird Flight as the Basis of Aviation) one of the classics of aeronautical literature.

Octave Chanute was a nationally known civil engineer who indulged his passion for aeronautics in his later years. He was the late nineteenth century’s Wikipedia of aeronautical information—collecting, organizing and freely sharing all that had been done to date in aeronautical research. He also designed gliders, supervised experiments and collaborated with other researchers. Historian Charles H. Gibbs-Smith ranked Chanute’s 1894 book Progress in Flying Machines second only to Lilienthal’s Vogelflug. Chanute’s double-deck wing design would strongly influence the Wright brothers in designing their own machines. The hundreds of letters he exchanged with them—mainly Wilbur—became invaluable records of their work.

Octave Chanute. George Grantham Bain Collection, Prints and Photographs Division, Library of Congress.

How soon Orville shared Wilbur’s passion for flight isn’t clear. Wilbur was always careful to share credit with his younger brother, but his letters about flight in 1899 and 1900 described his research as something he was doing alone. In later years, they nearly always described their work as something they did together.

That’s how they later described their digestion of the scientific literature. “The larger works gave us a good understanding of the nature of the flying problem, and the difficulties in past attempts to solve it, while Mouillard and Lilienthal, the great missionaries of the flying cause, infected us with their own unquenchable enthusiasm, and transformed idle curiosity into the active zeal of workers,” Orville wrote in the Century.

The Wright brothers found that experimenters had looked for ways to make a machine stable in flight—keeping it level from side to side and front to back. Turning received little attention; experimenters thought it merely required a rudder. One method for keeping the wings level from side to side—what experimenters called lateral stability—was to place the center of gravity well below the wings, figuring the weight would seek its lowest point. It did, but it also caused a pendulum motion. Another method was to shape the wings in a wide V, or dihedral. But this approach worked only in calm air, and any upset would cause side-to-side oscillation. A similar system was tried for front-to-back stability, with the center of gravity far forward and the tail acting as a counterbalance. But this resulted in a constant pitching motion, or undulation.

“We therefore resolved to try a fundamentally different principle. We would arrange the machine so that it would not tend to right itself,” Orville wrote in the Century. Instead of seeking passive stability, they would pursue active control “by some suitable contrivance.”

But what kind of contrivance? Lilienthal had controlled his gliders with the mass of his body, literally throwing his weight around beneath the wings to maintain stability. The Wright brothers immediately saw the flaw in this approach: weight shifting was limited by the mass of the operator, and its effectiveness would be diminished in bigger machines or stronger counterbalancing winds. “In order to meet the needs of large machines,” Orville wrote, “we 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.”

The Wright brothers’ solution for lateral control was a breakthrough concept that hurtled them beyond everyone else in aeronautics. Their idea was to increase the lift of one wing and reduce the lift of the other by adjusting the angle of their wingtips relative to the wind. The wing with more lift would rise while the wing with less lift would dip. With such a system, an operator could change the lateral balance as needed to counteract gusts. Instead of shifting his weight, an operator would simply work a control linked to both wingtips to roll the aircraft right or left. Today, pilots call it roll control.

This sculpture at Deeds Point in downtown Dayton portrays Orville twisting a bicycle inner tube box as Wilbur explains his wing warping idea. Author’s photo.

How to manipulate the wingtips wasn’t immediately obvious. At first the Wrights thought of rotating the wings in opposite directions on shafts connected by gears in the middle, but they quickly realized any device strong enough for the job would be too heavy. One day in the summer of 1899, Wilbur showed Orville how it could work. He took a cardboard box that had held bicycle inner tubes and twisted the ends in opposite directions. The upper and lower sides of the box remained parallel while the ends twisted up or down. This made it easy to imagine a stacked pair of wings, held apart by struts with flexible attachments, with a system of wires to twist the wingtips.

They quickly built a kite to test the idea. The kite featured a pair of sticks with lines connected to the front wingtips, which they could twist by working the sticks. Wilbur tested the kite while Orville was away on a camping trip and found that it worked perfectly.

Wilbur described this revolutionary idea on May 13, 1900, in his first letter to Chanute: “My observation of the flight of buzzards leads me to believe that they regain their lateral balance, when partly overturned by a gust of wind, by a torsion of the tips of the wings. If the rear edge of the right wingtip is twisted upward and the left downward the bird becomes an animated windmill” and quickly rights itself.

Chanute would coin a term for this method of twisting the wings. He called it “wing warping.” But his letters to Wilbur showed no sign that he grasped how manipulating the wingtips to change lift was fundamentally different from all previous attempts at lateral stability.

Fired with enthusiasm, Wilbur and Orville decided to build a glider that could carry one of them. But Dayton’s tree-covered hills, fitful winds and hard ground didn’t offer the conditions they needed for testing. They reviewed weather records and chose the Outer Banks of North Carolina, a place that offered steady wind and tall mounds of sand. The wind there, Wilbur wrote in a September 9, 1900 letter to their father from the coast, “is stronger than any place near home and almost constant so that it is not necessary to wait days or weeks for a suitable breeze.” Wilbur’s idea was to let the wind flowing up the dunes do the work. It would allow them to soar on an updraft over a single spot or glide downhill at low speeds relative to the ground. Either way, they wouldn’t have to risk crashing into the ground at high speed.

Wilbur set out for Kitty Hawk alone on September 6 and arrived on September 11. Orville joined him seventeen days later. Wilbur’s use of “I” instead of “we” in letters to their father clearly shows he thought of the project as his alone, not a collaboration. “It is my belief that flight is possible and while I am taking up the investigation for pleasure rather than profit, I think there is some slight possibility of achieving fame and fortune from it,” he wrote on September 3. In a September 23 letter from Kitty Hawk, Wilbur wrote, “I have my machine nearly finished.” He assured the bishop he would stay safe: “I do not intend to take dangerous chances. I have no wish to be hurt and [sic] because a fall would stop my experimenting which I would not like at all.” His words suggest he didn’t expect his brother to be at risk, and Orville didn’t begin gliding until 1902.

The 1900 glider had wings 17 feet long and 5 feet wide with a surface area of about 165 square feet. Ahead of the wings was an elevator, which the brothers called a “front rudder.” The glider’s large size reflected their confidence that their wing warping system freed them from the size limits dictated by weight shifting. The results they got from it convinced them they were on the right track. The wing-warping scheme worked, and the elevator showed they could control fore-and-aft balance, or pitch. The glider itself was rugged and easy to repair.

The 1900 glider flying as a kite at Kitty Hawk, North Carolina. Papers of Wilbur and Orville Wright, Prints and Photographs Division, Library of Congress.

Wilbur and Orville understood the basics of how a wing works. As it moves through the air, a wing’s curved upper surface causes the air to flow over the top faster than under the bottom. This results in a lower pressure over the wing than under it. The greater pressure under the wing supplies the lift. Increasing the angle of the wing to the wind increases its lift. This angle between the wing and the wind is what early experimenters called the angle of incidence; today’s aviators know it as the angle of attack.³

But there were subtle signs that flight might be trickier than it seemed. Flying the glider as a kite, the brothers measured its lift and drag and discovered both were lower than expected. It was their first hint that the data on which they had based their calculations was faulty.

They decided to return to Kitty Hawk the next year with a new glider that would allow them to experiment with their wing design. They had built it so they could easily change the camber of its wings. The 1901 glider was much bigger than the 1900 machine: each wing measured 22 by 7 feet, for a total surface area of 308 square feet. It was the biggest glider anyone had ever tried to fly. Its wings had twice the total area of Lilienthal’s glider and more than twice the area of the Chanute-Herring glider. It was another indication of their confidence in wing warping. “As the weight of the body is not moved in our plan of balancing, we think the large machine will not be much more difficult to control than a smaller one,” Wilbur wrote in a May 12, 1901 letter to Chanute.

On June 15, 1901, the Wright brothers hired Charles Taylor, a skilled machinist who had done some jobs for them. Taylor lived six blocks away at Calm and Gale Streets. His wife, Henrietta, was Charles Webbert’s niece. They left Taylor in charge of the shop when they went to Kitty Hawk. “So far as I can figure out, Wil and Orv hired me to worry about their bicycle business so they could concentrate on their flying studies and experiments,” Taylor wrote years later in an article for the December 25, 1948 issue of Collier’s Weekly magazine.

Charlie Taylor in 1911. Courtesy of Special Collections and Archives, Wright State University.

Wilbur and Orville returned to Kitty Hawk in July 1901. Wilbur’s first flights were disappointing. The glider’s elevator didn’t seem to control pitch as well as the 1900 glider’s, and its big wings generated much less lift than they had expected. They removed the top wing and flew it as a kite to gather data. The brothers were studying not just how much lift a wing creates with different camber but also how it performs at different angles to the wind. They studied how a spot called the center of pressure moves forward and backward on the wing, affecting the wing’s tendency to pitch up or down. They found the wing’s camber affects how the center of pressure moves. This makes a difference in how well the elevator can control the wing’s pitching. Retrussing the wings to reduce their camber solved the pitching problem.

Wilbur (left) and Orville fly the 1901 glider as a kite. Papers of Wilbur and Orville Wright, Prints and Photographs Division, Library of Congress.

Now it was time to try a turn. The Wright brothers understood that a vertical rudder wasn’t the way to turn an airplane—their 1900 and 1901 gliders didn’t even have them. The secret was to tilt the wings. When an airplane is tilted to one side, not all of its lift is vertical. Part of the lifting force pushes sideways in the direction of the tilt, and the airplane dutifully turns in that direction. By using the wing warping control to tilt the glider’s wings, Wilbur expected it to begin turning in a circle with the lower wings on the inside of the turn. That’s how it began, but then the glider suddenly made a yawing motion in the opposite direction. Startled, Wilbur leveled the wings and landed. He tried again and the same thing happened. This unexpected response “completely upsets our theories as to the causes which produce the turning to right or left,” Wilbur wrote to Chanute on August 22.

The experiments of 1901 shook their confidence in all they thought they knew about aviation—and in all the aeronautical literature they had assumed to be correct. “Having set out with absolute faith in the existing scientific data, we were driven to doubt one thing after another, till finally, after two years of experiment, we cast it all aside, and decided to rely entirely upon our own investigations,” Orville wrote in the Century.

Wilbur on the 1901 glider just after landing at Kitty Hawk. Note the skid marks in the foreground and background. Papers of Wilbur and Orville Wright, Prints and Photographs Division, Library of Congress.

Others might have given up, but the Wright brothers took the mysteries as a challenge. “We had taken up aeronautics merely as a sport. We reluctantly entered upon the scientific side of it. But we soon found the work so fascinating that we were drawn into it deeper and deeper,” Orville wrote.

One mystery was the lackluster performance of their wings. How big did a wing need to be to support a given weight in the air? What shape? How much lift and drag would it produce at different speeds? Other researchers had plowed this ground and developed formulas. Lilienthal had developed a coefficient of lift for the specific wing shape he had used on his glider and published a table of lift values for his wing at different angles of attack. Lilienthal was a highly respected pioneer. The Wright brothers relied on his work in designing their 1900 and 1901 gliders.

Now, Wilbur and Orville were suspicious. Drawing on their familiarity with bicycles, they found a clever way to test Lilienthal’s data with the materials at hand. They simply mounted two plates perpendicular to the rim of a bicycle wheel and then mounted the wheel horizontally on a bicycle in front of the handlebar. One plate was curved like Lilienthal’s wing; the other was flat and mounted at a ninety-degree angle to the curved one. As one of them pedaled the bike around their neighborhood, the air would flow past the curved plate and push against the flat plate. The wheel could turn freely, and it would rotate based on how much lift the curved plate generated in comparison to the force of the wind against the flat plate. With this simple instrument, they could roughly measure the lifting force at different angles of attack; according to Lilienthal’s table, the two plates should balance with the curved plate at a five-degree angle of attack. Instead, it required an angle of eighteen degrees—not even close.

The bicycle rig reinforced their suspicions, but they wanted more conclusive proof. The next step was a wind tunnel. At heart, a wind tunnel is a tube with air flowing through it and a way of measuring how the air stream acts on an object mounted inside it. Others had made them. Orville built one from an old starch box not more than eighteen inches long. He set a glass plate in the top for an observation window. They used their shop engine to drive a small fan that blew air through it. Orville used the same idea of a curved plate and a flat plate mounted on a balance, but it was more precise than a bicycle wheel. They used this tunnel for only one day, but it was enough. “I am now absolutely certain that Lilienthal’s table is very seriously in error,” Wilbur wrote to Chanute on October 6.⁴

But why was it wrong? Was the error in Lilienthal’s coefficient or somewhere else? The Wright brothers suspected a value that Lilienthal, Chanute and others had used in their formulas for lift and drag. In the mid-1700s, British engineer John Smeaton had developed a coefficient for determining the resistance of various fluids against a flat plate. The value Smeaton came up with for air was .005, and nobody questioned it for 150 years. By the beginning of the twentieth century, however, a number of people questioned his coefficient after testing it and getting different values. The Wright brothers were aware of the debate, but they had accepted Lilienthal’s judgment in sticking with Smeaton. Was it a mistake?

This replica of the Wright brothers’ 1901 wind tunnel is on display in the hangar-museum of Wright “B” Flyer, Inc. Author’s photo.

To find out, they took the lift measurements they had made at Kitty Hawk with their 1901 glider and worked the lift equation in reverse to find the value for Smeaton’s coefficient. They repeated the exercise using data from several glides. Instead of .005, they got an average value of .0033, close to the value other researchers had found.

The precision of their crude tunnel surprised Wilbur and Orville, and the results they got from a single day of tests were “so interesting” that the brothers decided to build a more elaborate tunnel and systematically gather data on a wide range of wing shapes.

The new tunnel was an open-ended wooden box about sixteen inches on a side and six feet long. The front end had a metal shroud that directed air through a set of crosshatched vanes to smooth the flow as it entered the tunnel. But the heart of the tunnel was its instrumentation: a pair of deceptively primitive-looking balances made from pieces of bicycle spokes and old hacksaw blades. In Visions of a Flying Machine: The Wright Brothers and the Process of Invention, historian Peter Jakab described them as “a mechanical representation of what the lift, and drag equations expressed mathematically.” One balance measured lift and the other measured drag. Each was ingeniously simple. The lift balance, for example, mechanically measured the coefficient of lift for a given surface at a given angle of attack and showed the value on a dial.⁵

The original 1901 wind tunnel airfoil and lift balance. Courtesy of Special Collections and Archives, Wright State University.

The wind tunnel turned 1127 West Third Street into an aeronautical laboratory. “It is perfectly marvelous to me how quickly you get results with your testing machine,” Chanute wrote on November 18. “You are evidently better equipped to test the endless variety of curved surfaces than anybody has ever been.”

Jakab and other aviation historians cite the Wright brothers’ wind tunnel work as an example of their systematic approach to the problem of flight. “Of all the experimenters who preceded them, none exhibited a more refined engineering style than Wilbur and Orville Wright,” Jakab wrote.

In October and early November, Wilbur and Orville ran preliminary tests on up to two hundred types of wing surfaces in various configurations. Their formal tests in late November included thirty-eight different model airfoils, some of them stacked two or three deep. The range of shapes also included airfoils of different aspect ratio—the ratio of a wing’s length to its chord, or the straight distance between the front and back edges. The tests gave the Wright brothers a guide to wing design that nobody else possessed—what Fred Howard in his biography Wilbur and Orville deemed “some of the most remarkable trade secrets of the century.”

People worldwide celebrate the Wright brothers for Orville’s first powered flight at Kitty Hawk, North Carolina, on December 17, 1903. An iconic photo that captures the moment of lift off no doubt contributes to the first flight’s fame. But their months of work in Dayton with the wind tunnel, painstakingly building models and recording data, was what made that moment achievable. The world, Kelly wrote, “is not fully aware of all the tedious, grueling scientific laboratory work they had to do before flight was possible.”

In the following months, Wilbur and Orville tended to their bicycle business while working on a new glider to test their new data. Some airplane work went on at 7 Hawthorn. The brothers commandeered the family sewing machine to make the new glider’s surfaces. “Will [as Katharine spelled Wilbur’s nickname] spins the sewing machine around by the hour while Orv squats around marking the places to sew,” Katharine wrote to their father on August 20, 1902. “There is no place in the house to live but I’ll be lonesome enough by this time next week and wish that I could have some of their racket around,” she added.

The next Wright machine was distinctly different from their previous gliders. The wings spanned thirty-two feet and measured five feet from front to back. Their total surface area was no greater than the 1901 glider’s, but their aspect ratio was about double. The new wing shape reflected the brothers’ wind tunnel work and their new understanding of the importance of aspect ratio in wing design. The 1902 glider also sported a tail boom with twin vertical fins for more directional stability. To a modern aviator’s eyes, it was the first Wright glider that looked like an airplane. Jakab called it “truly a thing of beauty.”

The bicycle business and the airplane work weren’t all that kept the Wright brothers busy during the spring and summer months of 1902. What Wilbur cryptically called “the church matter” demanded his time.

Back in 1889, the split between the Liberal and Radical factions of Bishop Wright’s church had left the Dayton publishing house, and nearly all other church property, in the hands of the New Constitution group. Bishop Wright, as publishing agent, had demanded they turn it over to his Old Constitution group. The Liberals had refused and filed for title to the property, which turned the dispute into a legal battle. The case dragged on for six years, when the Ohio Supreme Court finally decided in favor of the Liberals. In the meantime, Milton and his publications board built a new publishing arm in rented space in Dayton. Its main publication was the Christian Conservator.

But controversy grew even within the Radicals’ ranks. While the ongoing clashes between the factions kept Milton on the road, he grew suspicious that his successor as the elected publishing agent, Millard F. Keiter, was falsifying the publishing house’s financial records back in Dayton. Wilbur went over the books himself and found discrepancies. “We think there is something rotten somewhere,” he wrote to Milton on June 2, 1897. “He is either a liar, a thief, or an incompetent book keeper, or all three,” he added.

The publishing operation moved to Huntington, Indiana, that year, but the bishop remained suspicious. In 1901, the publishing board hired an accountant to audit the books; he reported funds were missing. The questions about Keiter’s accounting became a major issue at the church’s general conference that year, and Keiter wasn’t reelected. The auditor’s final report to the publishing board found an apparent shortage of $1,470. The controversy divided the publishing board, which met in Huntington from February 11 through February 14, 1902, before voting four to three to declare Keiter’s records correct.

Outraged at the apparent effort to sweep the affair under the rug, Milton launched a pamphlet campaign against Keiter. “Wilbur felt duty bound to give some help to his father,” Kelly wrote in his book Miracle at Kitty Hawk. Wilbur pored over the financial records and wrote a “blistering tract” for his father, one of several angry pamphlets the bishop distributed. The church controversy would continue until Milton eventually triumphed—and retired—in 1905.⁶

Side view of Dan Tate (left) and Wilbur flying the 1902 glider as a kite. Papers of Wilbur and Orville Wright, Prints and Photographs Division, Library of Congress.

But in July 1902, Wilbur felt torn between his duty to his father and his passion to fly. He wrote to Chanute on July 17 that the “church matter” might delay the brothers’ plans to return to Kitty Hawk. Even as they finished the glider, Wilbur wavered. “They are talking of going next Monday—though sometimes Will thinks he would like to stay and see what happens at Huntington next week,” Katharine wrote to Milton on August 20.

“They really ought to get away for awhile,” she added. “Will is thin and nervous and so is Orv. They will be all right when they get down in the sand where the salt breezes blow etc. They insist that, if you aren’t well enough to stay out on your trip, you must come down with them. They think that life at Kitty Hawk cures all ills, you know.”

The brothers returned to Kitty Hawk and spent the next several days restoring their old camp and building a new shed before assembling the glider. They finally carried it out to the smallest of the Kill Devil Hills for tests on September 19. They flew it as a kite first—an efficient way to gather basic data without risking their necks—then made about twenty-five glides. They made the first glides with the wing warping control locked so they could focus on mastering the new elevator and a redesigned elevator control.

Encouraged by the results, on September 23 they carried the glider to a one-hundred-foot-tall sand dune known as Big Kill Devil Hill for more ambitious tests. This was the first time since they had begun going to Kitty Hawk that Orville made untethered flights. On his third or fourth flight, Orville noticed the wings on one side rising. He tried to correct it by warping the wings to level them. Instead, the wings tipped higher. As Orville struggled to level the wings, he didn’t notice that the glider also was pitching up steeply. On the ground, Wilbur and Dan Tate, a local fisherman who often stopped by to help, watched it angling upward and shouted warnings, but the wind drowned their voices. The machine abruptly started sliding backward toward its low wing and plunged about twenty-five feet to the ground.

“The result was a heap of flying machine, cloth and sticks in a heap, with me in the center without a bruise or a scratch,” Orville wrote in his diary. The crash damaged their machine, and they knew the repairs would halt their flying for a few days. “In spite of this sad fact, we are tonight in a hilarious mood as a result of the encouraging performance of the machine,” Orville wrote.

It was the only serious damage the 1902 glider sustained. The warping wing design made the wings inherently flexible, but the Wrights also made the glider with crashes in mind. “It was built to withstand hard usage, and in nearly a thousand glides was injured but once,” Wilbur wrote in “Experiments and Observations in Soaring Flight,” a lecture printed in the August 1903 issue of the Journal of the Western Society of Engineers. They also tried to keep their flights close to the ground, often gliding for hundreds of feet while just a few feet or inches above the sand.

The Wright brothers had developed the concept of lateral control in Dayton, but only actual flying could reveal its true complexity. Kitty Hawk’s steady winds made it possible to fly at slow speeds over the ground, and the soft sand cushioned rough landings. These conditions allowed them to make hundreds of glides in 1902 without killing themselves. Glide by glide, they began learning how to fly.

The 1902 glider was the world’s first controllable airplane. Here Wilbur makes a right turn. Papers of Wilbur and Orville Wright, Prints and Photographs Division, Library of Congress.

The biggest puzzle they encountered was something they called “well-digging.” When a shift in the wind tipped the glider to one side, it would begin to slip sideways toward the low wings. This put more pressure on the down-facing side of the tail fin and caused it to swing the glider around the low wings. This slowed the low wings and accelerated the high ones, increasing their lift and causing them to tip up even more. If the pilot warped the wings to raise the low ones, the increased drag on the low wings did more to slow them than to raise them. The result was a corkscrewing motion that ended with the glider’s lowest wingtip digging a crater in the sand.

They had added the tail fins to solve the strange yawing motion Wilbur had experienced the previous year. Instead of solving the problem, the tail fin “made the machine absolutely dangerous,” Orville wrote in the Century. Was there any solution?

It came to Orville on the night of October 2 as he lay sleepless in one of the bunks they’d mounted just under the rafters: they needed to turn the fixed tailfin into a rudder. In a well-digging situation, the operator could turn the rudder to relieve the pressure on the low-wing side and increase pressure on the high-wing side, helping to rebalance the forces. Historians say it isn’t clear exactly how the brothers came up with this solution, but Orville noted the idea in his diary the next day. Eventually, they removed one of the two fins and made the other one adjustable. “After the adjustable rudder was installed not once did we encounter the difficulty we had experienced with the fixed vane,” Wilbur said later.⁷

The rudder was also what they needed to solve the yawing problem. Just as Wilbur had figured, the glider started to turn when he tilted it by warping the wings to increase the lift on one side and reduce it on the other. But the wings with more lift also had more drag. This slowed the higher wings, forcing the glider’s nose to swing away from the direction of the turn. This strange behavior is what pilots today call adverse yaw. What Orville discovered was that an airplane did need a rudder—not to make a turn but to coordinate it. The rudder allowed Wilbur and Orville to balance the opposing forces of lift and drag in a turn. With a rudder, the 1902 Wright glider became the first machine truly capable of controlled flight.⁸

The success of the 1902 glider convinced the Wright brothers they were ready to build a powered machine. They returned to Dayton on October 31, and by the end of the year, they were testing propellers and working on an engine.

After all the work of figuring out how to design wings, they assumed designing a propeller—really just a rotating wing—would be a small detail. They would only need to apply their tables to the formulas marine engineers used to design marine screws—or so they thought. They discovered marine engineers had no theory for marine screw performance that could help them predict propeller performance. They would either have to work by trial and error or come up with their own theory. As Orville wrote in the Century:

The 1903 flyer prior to Wilbur’s flight attempt on December 14. The group includes four men from the Kill Devil Hills Lifesaving Station, two small boys and a dog. Papers of Wilbur and Orville Wright, Prints and Photographs Division, Library of Congress.

What at first seemed a simple problem became more complex the longer we studied it. With the machine moving forward, the air flying backward, the propellers turning sidewise, and nothing standing still, it seemed impossible to find a starting-point from which to trace the various simultaneous reactions. Contemplation of it was confusing. After long arguments, we often found ourselves in the ludicrous position of each having been converted to the other’s side, with no more agreement than when the discussion began.⁹

Wilbur and Orville persevered, eventually developing propellers that were much more efficient than any earlier designs. But they still lacked an engine to turn them. They needed one that could deliver eight or nine horsepower and weigh no more than 180 pounds. They couldn’t find any commercial engines that met their needs, so they directed Taylor to make one.

Front view of the 1903 Wright Flyer motor. Courtesy of Special Collections and Archives, Wright State University.

“We didn’t make any drawings. One of us would sketch out the part we were talking about on a piece of scratch paper and I’d spike the sketch over my bench,” Taylor wrote in his Collier’s Weekly article. “It took me six weeks to make that engine. The only metal-working machines we had were a lathe and a drill press, run by belts from the stationary gas engine.”

Taylor made the crankshaft by tracing the outline on a block of machine steel, drilling holes along the outline with the drill press and then chiseling off the excess hunks of metal like a sculptor. He put the rough part in a lathe and turned it down to the correct size and smoothness. “It weighed nineteen pounds finished and she balanced up perfectly, too,” he boasted in his article.

A local foundry made castings for the aluminum crankcase and iron cylinder barrels, pistons and rings. Taylor bored cylinder holes in the crankcase with the lathe. The 1903 engine didn’t use spark plugs but what Taylor called “make or break” electrical contact points inside the combustion chamber that were operated by shafts and cams geared to the main camshaft. A battery was connected to the engine for starting, but once started, a magneto supplied the spark and the battery was removed. Fuel flowed by gravity from a one-gallon fuel tank mounted on a wing strut. Instead of mixing with air in a carburetor, the fuel flowed into a shallow chamber in the manifold next to the cylinders, where the heat quickly vaporized it. They started the engine by priming each cylinder with a few drops of gasoline. Cooling water circulated through thin jackets around the cylinders to a radiator.

They tested the new engine for the first time on February 12, but the engine body and frame broke the next day in another test. They ordered a new casting and had the new engine running by May.

The 1903 Wright Flyer reflected its bicycle-shop roots. Its drive system used chains and sprocket wheels to turn the twin propellers. The single-rail launching track also reflected bicycle locomotion. The track was a series of wooden beams, set on edge and capped with a metal strip. The flyer rode down the track on a truck, essentially a wooden platform on a pair of inline rollers. The rollers were modified bicycle hubs; enlarged flanges straddled the track, acting as guides.

While they made the parts for the 1903 Flyer in Dayton, they didn’t fully assemble it there because the bicycle shop was too small. Waiting until they were on the Outer Banks to assemble and ground-run the machine took extra time and effort. They learned the hard way that the propeller shafts were too weak. One broke during a power test on November 5. Wilbur and Orville shipped the shaft back to Taylor for repair, but it broke again on November 28. Orville had to return to Dayton to assist Taylor in building new ones. He left Dayton with new shafts on December 9 and arrived back in Kitty Hawk on December 11.

Wilbur in the damaged 1903 Flyer, moments after his unsuccessful flight attempt on December 14, 1917. Courtesy of Special Collections and Archives, Wright State University.

They set up the track on the slope of Big Kill Devil Hill on December 14. They tossed a coin to see who would make the first flight attempt. Wilbur won. The flyer took off, but it stalled after three and a half seconds and settled to the ground 105 feet downhill from its takeoff point. They didn’t count it as a flight. They tried again on December 17, this time on flat ground. Now it was Orville’s turn.

Orville described the historic flight without emotion in his diary:

On slipping the rope the machine started off increasing in speed to probably 7 or 8 miles. The machine lifted from the truck just as it was entering on the fourth rail. Mr. Daniels took a picture just as it left the tracks. I found the control of the front rudder quite difficult on account of its being balanced too near the center and thus had a tendency to turn itself when started so that the rudder was turned too far on one side and then too far on the other. As a result the machine would rise suddenly to about 10 ft. and then as suddenly, on turning the rudder, dart for the ground. A sudden dart when out about 100 feet from the end of the tracks ended the flight.¹⁰

John T. Daniels’s iconic photo of Orville Wright making the first powered flight on December 17, 1903. Courtesy of Special Collections and Archives, Wright State University.

The flight covered 120 feet in twelve seconds, but given a 45-foot-per-second headwind, Orville calculated the flight was equivalent to 540 feet in calm air. “The flight lasted only 12 seconds,” Kelly wrote in The Wright Brothers, “but it was nevertheless the first in the history of the world in which a machine carrying a man had raised itself by its own power into the air in full flight, had sailed forward without reduction of speed, and had finally landed at a point as high as that from which it started.”

Orville sent a telegram from the lifesaving station at Kitty Hawk to their father back in Dayton, relayed through a telegraph office in Norfolk, Virginia. The Norfolk telegraph operator—against Orville’s instructions—leaked it to a reporter at the Norfolk Virginian-Pilot. Most journalists had little understanding of flight. Some had heard of the powered blimp the Brazilian Alberto Santos-Dumont was flying to great acclaim in France. But the notion that wings could lift a flying machine was often beyond their grasp. The Norfolk reporter invented grossly inaccurate details to explain the flight, such as a six-bladed propeller mounted under the aircraft to push it up. The newspaper splashed the story across its front page and offered it to others; a few papers across the country reprinted it, including the Dayton Herald.

But the widespread belief that the Dayton press ignored or badly misrepresented the facts is false. The December 18 Dayton Journal and the evening edition of the Dayton Daily News got nearly all the facts right. Their identical wording suggests they used a press release from the Wright family. “The Wright Flyer is a true flying machine. It has no gas bag or balloon attachments of any kind, but is supported by a pair of aero-curves or wings,” both papers reported. They continued, “The machine is driven by a pair of aerial screw propellers placed just behind the main wings. The power is supplied by a gasoline engine designed and built by the Messrs. Wright in their own shop.”

The Daily News noted that earlier reports based on the dispatch from Norfolk were inaccurate. But the magnitude of the achievement was lost on the copyeditor who wrote the headline: “Dayton boys emulate great Santos-Dumont.”

This wasn’t even the first time the Dayton papers reported on the Wright brothers’ work. The Saturday magazine section of the January 25, 1902 Daily News reprinted Wilbur’s 1901 lecture to the Western Society of Engineers, accompanied by illustrations derived from photos of their glider experiments.

The brothers soon heard from Augustus Herring, another experimenter who had worked with Chanute. Herring had visited their Kitty Hawk camp with Chanute in 1902. Herring claimed he had independently found a solution to powered flight and suggested forming a partnership with the Wright brothers that would include a one-third interest for him. He also claimed to be the originator of Chanute’s biplane glider and said he had been offered money for his rights to interference suits against the Wrights. They ignored his letter.¹¹

The public and newspaper editors greeted word of the Wright brothers’ achievement with a mixture of indifference, skepticism and utter confusion. No wonder; the list of people who had attacked the problem and failed read like a who’s who of famous inventors, from Leonardo da Vinci to Thomas Edison. Nine years earlier, machine-gun inventor Hiram Maxim’s four-ton, steam-powered beast had struggled to rise a few inches from its railroad-like track before crashing. Lilienthal, of course, had died. Most recent was Samuel Pierpont Langley’s tandem-wing Aerodrome, funded by $50,000 of taxpayer money under an army contract. His spectacular failure had come just as the Wright brothers were achieving success. On October 7 and again on December 8 in 1903, Langley had tried to catapult the gangly contraption from a boat in the Potomac River with assistant Charles Manly at the controls. Each time, the Aerodrome had folded up and dropped into the water. Renowned astronomer and mathematician Simon Newcomb said attempting to fly was like “squaring the circle.” The press ridiculed Langley for even trying.¹²