Wright Brothers – History of Flight

“The desire to fly,” wrote Wilbur Wright, “is an idea handed down to us by our ancestors who, in their grueling travels across trackless lands in prehistoric times, looked enviously on the birds soaring freely through space, at full speed, above all obstacles, on the infinite highway of the air.”

Daedalus and Icarus

One of the earliest tales of flying comes from the Greek myth that tells of Daedalus and his son, Icarus. They sought to escape imprisonment by King Minos on the island of Crete by flying from captivity using wings made of feathers held together by wax. Daedalus warned his son not to fly too close to the sun, but he ignored his father’s warning and the wax in his wings melted and he plunged into the sea and drowned.

Leonardo da Vinci

Early attempts to fly were made by trying to mimic the birds by flapping wings. Human arms are too weak to flap wings for long so machines were designed to aid arms or legs to perform flapping. Such machines are known as “ornithopters.”

Some of the earliest ornithopter designs were made by Leonardo da Vinci from the early 1480s until almost his death in 1519. Leonardo sketched many different designs in his notebooks based on his scientific studies on the mechanism by which a bird flies. As far as is known, he never built any of his machines. It is just as well because his designs lacked in aerodynamic qualities.

Although he was not successful in designing a successful flying machine, his heritage for those to follow was in his approach of using the scientific method. The inscription, “There Shall Be Wings” on the Wright Memorial at Kitty Hawk, N.C. is a quotation from da Vinci.

Sir George Cayley

Cayley, a baronet and engineer who lived on an estate in Yorkshire, England, was the first to advance the concept of the modern airplane. “The whole problem,” Cayley wrote, “is confined within these limits – to make a surface support a given weight by application of power to the resistance of air.”

He published three articles during 1809-10 on his aeronautical research entitled “Aerial Navigation” in which he correctly concluded that (1) lift is generated by a region of low pressure on the upper surface of the wing and (2) cambered wings generate lift more efficiently than a flat surface.

He used his findings to design a model glider in 1804 with an up-angled front fixed wing and a stabilizing tail.

A serious deficiency of his design was the use of “flappers” as the means of propulsion. This feature was useless.

In 1853, at the age of 80, he built a full-size glider that carried his reluctant coachman in a flight across a small valley.

William Henson

Henson, a contemporary of Cayley tried to use Cayley’s ideas to design a practical airplane propelled by a steam engine. It was known as the “Aerial Steam Carriage” and he received a patent for it in 1842. His design was the first to provide for the use of airscrews to power a fixed-wing monoplane. His structural design and bracing system anticipated modern design.

His design employed a separate tail and elevator and cambered wings with a 20-foot wing span. He added two vertical fan wheels back of the fixed wings that were powered by a lightweight steam engine to propel the machine through the air. A small model was built of the machine and tested without success.

John Stringfellow

Stringfellow, another contemporary, built an improved model in 1848. He launched it by running it down a sloping wire for 33 feet and then released it with the engine running. Allegedly, the model demonstrated true powered flight by climbing a little before it hit a wall.

The steam engine was simply too heavy for the power it produced. Powered flight would have to wait until the invention of a compact gas engine. The Smithsonian has in its possession a Stringfellow small one-horsepower steam engine.

Alphonse Penaud

Penaud, a Frenchman, was the first to use twisted rubber bands as motive power in a model helicopter. The helicopter would rise easily to the ceiling when operated and became a popular toy for children, including the Wright Brothers.

In 1876, he patented an airplane design that was remarkably similar to modern aircraft. The design included a “joy-stick” for the purpose of controlling horizontal and vertical rudders, a feature that anticipated the control system used by the Wright Brothers. Failing to obtain the financing to build his aircraft, he became depressed and committed suicide at the young age of 30.

Francis Wenham

Wenham, another Englishman, designed, built and used the first wind tunnel in 1871. His tunnel consisted of a long wooden box with a steam-driven fan at one end.

His studies demonstrated that a cambered wing was more effective for lift than a flat wing and that a wing’s leading edge provided most of the lift. As a result, a long narrow wing would create more lift than a short stubby one.

He further advocated the use of several wings on top of each other and obtained the first patent on a flying machine that used superposed planes. From his work he became known as the “father of the biplane,” a design used by the Wrights.

Horatio Phillips

Phillips was the second Englishman to build and use a crude wind tunnel to explore the curvature of wing airfoil shapes. He used steam to observe the movement of air along various surfaces. He wrote, “The particles of air struck by the convex upper surface…are deflected upward…thereby causing a partial vacuum over the greater portion of the upper surface.”

In 1892, Phillips designed a machine with 50 wing slats called a “multiplane.” It looked like a flying Venetian blind. It managed to fly for a short hop, but didn’t impress anyone.

He received a number of patents on his wing shapes in 1884 and 1891.

Otto Lilienthal

Lilienthal designed and flew the first successful gliders in history. They resembled today’s hang gliders.

He started his flying experiments about 1867 as a young boy in Germany. With the help of his brother, Gustav, he built a series of small gliders and successfully flew controlled flights with them.

In his home he built a whirling arm device that he used to collect the amount of pressure on a wing that would be obtained at various angles of incidence. In 1889 he published a classic in aeronautical literature, “Birdflight as the Basis of Aviation.” The Wright Brothers used data from the book in designing their 1900 and 1901 gliders.

Subsequently, the Wrights found inaccuracies in the data and based their successful 1902 glider and the 1903 Wright Flyer on data they derived from their own wind tunnel experiments

During the period 1891-1896, Lilienthal made over 2,500 successful glider flights. He would support himself on his forearms and control the glider by swinging his legs to shift its center of gravity. He believed that success in gliding was a necessary prerequisite before considering adding an engine for powered flight. The Wright Brothers took this advice to heart.

While gliding on August 9, 1896, Lilienthal was hit by a sudden gust of wind that tossed his glider upward to an altitude of 50 feet at an acute angle. Lilienthal immediately threw his weight forward and tried to bring the nose down. It was too late. The glider stalled, its left wing dipped sharply and plunged to the ground. He died the next day of a broken spine at the age of 48.

The incident was read with interest by the Wright Brothers and is credited with awaking their interest in the solving the riddle of successful flight by man. Wilbur called Lilienthal “the greatest of the precursors.”

Octave Chanute

Chanute, a well to do businessman, civil engineer and railroad bridge builder, was well beyond middle age when he became interested in aviation. He conducted flights with multi-wing gliders on the shores of Lake Michigan in 1896 searching for a design that would provide automatic stability. The experiments convinced him that it was possible to develop an inherently stable airplane.

He carried on correspondence with airplane experimenters all over the world and was soon regarded as an expert on the history of aviation. In 1894 he published, “Progress in Flying Machines.” It was considered the reference book for anyone interested in flight.

The Wright Brothers became aware of the book after Wilbur’s inquiry to the Smithsonian in May 1899. Wilbur wrote, “I have been interested in the problem of mechanical and human flight ever since as a boy I constructed a number of bats of various sizes after the style of Cayley’s and Penaud’s machines.” Wilbur continued, “I am an enthusiast, but not a crank in the sense that I have some pet theories as to the proper construction of a flying machine. I wish to avail myself of all that is already known and then if possible add my mite to help on the future worker who will attain final success.”

Wilbur wrote Chanute on May 13, 1900 to introduce himself saying, “For some years I have been inflicted with the belief that flight is possible to man.” It was the beginning of a ten-year close relationship between Chanute and Wilbur. Chanute was forty-five years older than Wilbur was, but the age difference was not apparent in the several hundred letters between the two. Chanute also visited the Wrights at their home in Dayton and at Kitty Hawk during their glider experiments.

Wright Brothers

After the Wrights completed their review of the literature, they were struck by the realization that there was really little known about the subject of flying. Orville wrote, “So many attempts to solve the flying problems started with the same idea and stopped at the same point. Most of them resulted in little or no advance over what had been done before.  To my mind Sir George Cayley was the first of the important pioneers. Leonardo da Vinci was a wonderful genius, but I cannot think of anything he contributed to the art of human flight.”

Wilbur and Orville were particularly surprised to find that no one had successfully solved the basic problem of flight control. From the beginning of their research, the Wrights knew they had to control rolling and not just pitching as their contemporaries had emphasized.

Orville wrote, “When we went to Kitty Hawk in 1900 we thought the fore-and-aft balance the difficult problem of equilibrium. We got this idea from reading Lilienthal, Chanute, and others. They gave very little space in their writings to lateral equilibrium.”

Many of the aviation pioneers had been injured and even died because of control problems. The Wrights did not think that controlling flight by body movements or a self-stabilizing design was going to lead to a solution.

Wilbur, while watching buzzards fly along the banks of the Miami River in Dayton, noticed that the birds regained their lateral balance by a slight twisting of their wing tips. That idea lead to the Wrights’ concept of wing-warping (twisting the wings).

They experimented with the idea using Chanute-type gliders at Kitty Hawk and found hat the idea worked.

The twisting of the wings along with the coordinated movement of the tail solved the control problem of flight and enabled the Wright Brothers to fly the first successful powered, heavier than air, manned, airplane.

The Wrights acknowledged those who went before them, but they owed them little, for their success came from their own painstaking work. It was they who had tested each idea derived from their own scientific imagination and invented the means to test. They replaced the trial and error approach of their predecessors with the scientific method and in so doing founded the profession of modern aeronautical engineering.

Earlier experimenters had failed because their machines were not aeronautically sound, but they did keep the dream of man’s quest to fly alive. It took the genius of the Wright Brothers to fulfill that dream.

Leonardo da Vinci, one of the most creative genius of the Renaissance, had an enduring infatuation with flying during the period between 1488 to 1514, a time when Columbus discovered America. His obsession drove him to write a collection of manuscripts with over 500 sketches on the topic. Many of his ideas were a precursor of the modern airplane.

His most famous flying machine designs were ornithopters, or machines that were to be powered by man by flapping bat-like wings like a bird.

In one of his best known designs, a man lies face down on the body of the machine and flaps the wings by pumping the stirrups with his legs much like modern pedal powered airplanes.

Just as the Wright Brothers, da Vinci based his ideas on the study of bird flight. He observed that: “A bird is an instrument working according to mathematical law, an instrument which is within the capacity of man to reproduce with all its movements.”

Implicit in his statement is that da Vinci was searching for the governing laws upon which bird flight is made possible. Knowing these laws, he could then use them to design a machine.

He was the first person to understand the mechanics of bird flight. From his observations he came to realize that the up-and-down flapping of the bird’s wings did not contribute much to lift. What the flapping did do was provide thrust for propulsion.

Da Vinci was the first to consider the scientific concept of lift, the force that enables a flying machine to fly.

His initial concept of lift was wrong. He thought that a high-pressure, high-density region of air was formed under a lifting surface that in turn exerted an upward force on that surface.

Later in life he changed his ideas on lift to the correct modern concept that lift is created primarily because the pressure over the top of a wing is less that the pressure on the bottom of the wing as air flows over it.

He invented the first barometer and anemometer to use in his studies.

Da Vinci also concluded correctly that a flying machine could have fixed wings and have a separate mechanism for propulsion, a thoroughly modern idea.

Additionally, He understood the phenomenon of drag, the resistance that a body incurs when moving through air. He postulated that both lift and drag were proportional to the surface area of the body and velocity of the wind over the body.

He was partially correct on the relationships. The velocity function is actually “velocity squared.”

He further understood that streamlining the shape of a body would reduce drag. In this regard he said that the streamlined shape of fish aids them in maneuvering in water.

His sketches of various flow patterns of airflow around a body represent the first qualitative understanding of experimental aerodynamics.

Da Vinci was the first to recognize that when studying the flow of air over a body, it didn’t make any difference whether the body was moving through still air or whether the air was moving over a stationary body as long as the relative velocity was the same in both cases. This insight provided the basis for the use of wind tunnels as a tool in the of study aerodynamics.

Safety of the pilot was a concern of da Vinci. He invented the first parachute using the model of a kite. The kite is an old technology, having been invented in China around 1000 BC.

It is obvious that da Vinci made significant contributions to the state of the art of aerodynamics. Unfortunately, after his death in 1519, his contributions were not available for use by others until the nineteenth and twentieth centuries. By that time it was too late to add to what others had discovered.

The problem was that he never published his work nor constructed or flew any of his machines. All of his ideas were in his notes and these were difficult to interpret because he wrote in a reverse mirror-like fashion. After his death the notes were dispersed and essentially became lost from view. Most people know of him for his famous paintings of the Last Supper and the Mona Lisa.

Sir George Cayley did not rediscover da Vinci’s ideas on lift and drag and the concept of a fixed-wing airplane until three centuries later in 1809. Cayley did not have the benefit of da Vinci’s notes.

By the time the Wright Brothers began construction of their 1900 glider, they had researched the available aerodynamic data of the day. It is not known whether they had in their extensive library any information on da Vinci.

The work of their predecessors did not furnish the Wrights with many answers but it did help them focus on the problems to be solved.

The Wrights, using a wind tunnel they constructed, contributed to the advancement of engineering knowledge on calculating lift and drag and design of airfoils.

Their most revolutionary contribution was the concept of wing warping for lateral control of a flying machine. Wilbur’s inspiration for this idea came from watching birds; much as da Vinci had done centuries before.

The Wright brothers owned a flying school at Nassau Boulevard, Long Island, New York. This is a true story of James, who was undergoing pilot training at the school. His instructor was Kellum, who was a former star pilot for the Wrights’.

James and Kellum arrived at the flying field early in the morning to begin the day’s training. They started early because the morning air is calmer and thus easier to fly in. Also, there were fewer spectators and therefore less danger of running them down when they ran onto the field, as they were apt to do.

James jumped into the pilot’s seat, grasped the controls rather theatrically and shouted to the mechanicians, “All right, start her up!”

Two men in blue overalls took hold of the wooden propellers.

Others grasped the tail of the machine and dug their heels in the grass with the evident intent of holding it a captive.

The instructor, Kellum, put his hands to his mouth and shouted:

“Remember James, don’t leave the ground? Just cross the field and shut off your engine at the other end.” He then nodded his head to the figures in overalls.

Instantly they twisted the propellers, casually at first, as if expecting no result. Then they whirled them harder, and a feeble coughing emanated from the engine.

Harder, and harder, and the cough grew into a grumble, a snarl; an angry roaring. Then the motor began to explode freely and the two propellers slashed through the air.

Now, the machine was trembling — an inanimate thing, suddenly given life, swaying slightly, eager to spring forward.

Behind the propellers the grass was blown flat; the men were clinging to the tail, pulling as one does in a tug of war.

The explosions increased in volume; a bluish smoke drifted between the planes.

The instructor waved his hands to signal the men to release their hold and some of them fell face forward as the machine jumped across the grass.

Down the field it hopped, gathering speed with every turn of the propellers.

Kellum explained, “That is what we call grass cutting. After they teach a fledgling the principles of the aeroplane and his mechanical knowledge is perfect, they let him drive over the grass.”

“The purpose of grass cutting is to give the student the instinct for control and to accustom him to the feel of the machine. Before the student acquires these things any attempt to fly would be dangerous and foolhardy.”

“The student spends days at this and later weeks at simply lifting a few feet and coming down. James, for instance, would no more attempt to leave than a spectator would.”

“Some day soon I will tell him he is equipped to fly and then he will, but not before.”

Kellum looked to see what had become of James, the grass cutter, and was shocked to observe that the biplane was headed for a fence. The motor was roaring and James was apparently making no attempt to shut it off.

Kellum exclaimed, “Oh! He is going up!”

Vividly against the spreading gold of the eastern sky you could make out the silhouette of the aeroplane as it rose from the ground. Farther and farther it went. Soon, all you could see was a black dot in the sky apparently headed for Garden City.

Then James tipped his wings one above the other and the machine banked and turned level with the horizon, and turning again came flying back toward the airfield.

Louder and louder grew the droning of the engine and all of the sudden he was over the airfield.

Kellum shouted: “Come down! Come down!” He forgot that he couldn’t be heard over the noise of the engine.

The machine turned and swooped down the field, crossing the horizon as it had done before and soaring back toward the airfield. Again the circuit was completed.

James’s mastery of the biplane was perfect; the turns were wonderfully executed; a level keel was kept.

The mechanicians were talking excitedly and gesticulating, marveling at the superb driving.

Kellum was not so happy. He knew that James was unfitted to be swooping above the field. Only kind Providence must be guiding the machine. It was a serious breach of the discipline of the school. Other students seeing James’s success, might venture into the air and possibly kill themselves

“We will have to expel James.”

James had turned and he was waving frantically with his left hand as if it was a sign of triumph as he flew overhead and down the field.

Suddenly one of the mechanicians darted to his side. “Hurry!” He shouted. “Run down the field. He’s trying to tell us that he wants to come down, and he wants us over there to stop him.”

Already the figures in blue were swarming over the grass. The biplane was descending.

“Shut off your motor!” somebody yelled. The cylinders continued rumbling, however, swooping down, the machine dashed across the grass. The mechanicians threw themselves on the tail and with their weight managed to bring the machine to a halt.

Still the engine was roaring and the propellers hacking.

“Shut off the engine! Shut off!” yelled Kellum.

Then one of the mechanicians reached in and moved the throttle, and the mad whirling of the propellers ceased.

James rose stiffly in his seat, and, stepping out, he sank to the ground exhausted.

People were congratulating him for his wonderful flight when Kellum, scowling, shouldered himself through the crowd. “What did you go up for?”

“I couldn’t stop the motor when I got to the other end of the field,” said James weakly. “I broke the throttle cord. If I hadn’t gone up, I would have smashed into the fence. It was my only chance.”

“Nonsense!” said Kellum, “If you’d simply pressed your foot against the brake it would have cut of the magneto and the engine would have stopped!”

James looked at him in wide-mouthed amazement. “So I could,” he grinned, sheepishly. “I never thought of that.”

Whereupon Kellum cast his hands overhead in a gesture of helplessness.

Such was one event at the flying school.

Student pilots paid $500 tuition. But that was just the beginning. Any item broken, including a whole machine had to be paid for by the student. The machines were valued at $5,000. Students also had to pay their own medical bills, if injured.

The instructors were often paid as much as $200 a week. They also received a special fee every time they left the ground in an airplane.

Reference: Harper’s Weekly, 1912.

The Wright brothers didn’t use parachutes although parachutes existed long before the Wright brothers introduced the airplane to the world. Leonardo da Vinci designed a parachute centuries ago and dare devils jumped out of balloons with parachutes in more recent years.

The introduction of the parachute to airplane pilots occurred during WW I when it became apparent that lives could be saved. German pilots were the first to use them. The Germans designed a chute that could be harnessed on the pilot’s back and could be deployed safely after bailing out of an airplane airplane. The pilot was saved to fly again.

The Americans had chutes but were poorly designed and often became tangled with the airplane while exiting.

General William Mitchell, commander of the U.S. Air Corps in France, observing the success of the Germans, was influential in establishing a parachute center at the Air Force’s Engineering Center at McCook Field in Dayton, Ohio in 1918.

Earlier, Captain Albert Berry was the first pilot to make a successful jump from a moving airplane in March 1912 at an U.S. Army Base located just outside St. Louis. He jumped at 1,500 feet while flying at 55 mph. His chute opened after a fall of 500 feet.

The parachute he used was too bulky to be strapped to his back, instead it was carried in an iron cone fastened to the airplane’s undercarriage. Two ropes connected to a trapeze-like bar hung out of the mouth of the cone. Two leg loops were provided at the end of the bar.

Berry had to climb down the fuselage to the axle while steadying himself with the trapeze bar, slide a belt around his waist and then cut himself away. All this time the pilot had to fly the biplane as level as he could. One rapid movement in any direction would be fatal to Berry.

Despite the difficulty involved, Berry reached the ground safely.

Nine days later he decided to repeat the feat, this time before the public. This time the airplane flew lower at 800 feet to assure that the crowd had a good view of him.

All did not go well this time and the lower altitude almost cost Berry his life. The parachute somehow got below him and was seconds away from becoming tangled in the canopy. Fortunately, he was able to right the chute with enough time to reach the ground safely. Berry decided that was enough parachuting for him and he never tried it again.

On December 17, 2006 the First Flight Society enshrined Albert Berry in the Wright Brothers Memorial visitor’s center in Kitty Hawk, NC.

Berry’s two jumps were admirable, but not practical. The Army Air Corps needed something that didn’t require a circus act for pilots to use in an emergency.

As noted earlier, the Engineering Division at McCook Field was given the job and they developed a parachute that was lightweight while retaining great strength. It was made of Japanese silk, attached to a harness of linen webbing with dimensions 24 feet high and 19 1/2 feet in diameter in the open position.

With hinges attached, the weight of the parachute was 17 1/2 pounds yet it withstood a tensile strain of approximately 10,000 pounds. Metal fittings were of drop forged nickel steel, subjected to a pull test of 2,500 pounds each before assembly into the harness. These strengths were designed to withstand the forces met when a pilot is forced to leave his airplane going at a high speed.

On October 19, 1922 Lt. Harold Harris was the first pilot to jump from a disabled airplane with a manually operated parachute that saved his life. At the time he was flying a test flight over Dayton, Ohio.

His Loening W-2A fighter plane had been outfitted with new ailerons that were supposed to be more aerodynamic with improved maneuverability. He was participating in a mock dogfight when his ailerons whipped up and down, tearing the wing’s fabric surfaces and sending his plane plunging toward the earth.

The windblast scooped Harris out of the cockpit. He was able to manually activate his parachute and save his life. The parachute had been tested under experimental conditions, but never before in an actual emergency situation.

After Harris’ jump the Army required airmen to wear parachutes on all flights.

References: “Albert Berry’s Leap of Fate,” Aviation History, March 2007

“A Little Journey to the Home of the Engineering Div. Army Air Service, McCook Field,” undated.