Wright Brothers – History of Flight

Articles relating to the history of the first flight.

Da Vinci’s Aerodynamics

by Dr. Richard Stimson

in History of Flight

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.

Learning to Fly in 1912

by Dr. Richard Stimson

in History of Flight

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 Parachute

by Dr. Richard Stimson

in History of Flight

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.

The ancestors of ancient birds may have resembled the Wright brother’s 1903 biwing airplane. So wrote scientist Sankar Chatterjee of Texas Tech University. A new study of the bones of a 125 million-year-old Chinese dinosaur suggests that they had upper and lower set of wings much like the biplanes of the Wright brothers.

The dinosaur called Microraptor gui used a two-level wing configuration that permitted the small 2-pound creature to glide from tree to tree. The 6-inch dinosaur had feathers on its legs that it folded under its body in flight, creating two staggered wing sections one slightly behind the other.

It appears that the dinosaur was tree-dwelling and took advantage of gravity to glide from tree to tree.

The Wrights observed birds to learn insights about flight. They concluded that control, particularly the roll component, was the key to man-flight. Birds mastered roll by twisting their wings. And like birds, a pilot could twist the wings of an airplane using a technique they named wing warping.

The Wrights used the biwing structure as a practical design for wing warping. Wilbur got the idea while twisting a bicycle tube box talking to a customer in their bicycle shop.

The dinosaur called “Microraptor gui” used a two-level wing configuration that permitted the small 2-pound creature to glide from tree to tree. The 6-inch dinosaur had feathers on its legs that it folded under its body in flight, creating two staggered wing sections one slightly behind the other.

It appears that the dinosaur was tree-dwelling and took advantage of gravity to glide from tree to tree.

The Wrights observed birds to learn insights about flight. They concluded that control, particularly the roll component, was the key to man-flight. Birds mastered roll by twisting their wings. And like birds, a pilot could twist the wings of an airplane using a technique they named wing warping.

The Wrights used the biwing structure as a practical design for wing warping. Wilbur got the idea while twisting a bicycle tube box talking to a customer in their bicycle shop.

The Brazilian inventor and aviation pioneer Alberto Santos-Dumont is popular this year in the United States. A replica of his 1906 airplane, the 14-bis, visited the Oshkosh AirVenture 2006.

In September, a replica of Dumont’s 1907 Demoiselle make public flights at the Dayton-Wright Brothers airport in Miamisburg, Ohio south of Dayton.

In 1904 after visiting the U.S. and learning of the Wright brothers success, Santos-Dumont returned to Paris to build his own machine. He originally moved to France to study engineering in the late 1800s.

In 1906 he created his 14-bis machine so named because it was first tested under his Airship (balloon) No. 14. On September 13, 1906 he achieved a “hop” flight of 23 ft in 7 seconds.

After repairs to the machine resulting from a crash landing on the previous flight, and the addition of a 50-hp engine, he flew 198 feet in seven seconds on Oct. 23. This flight won the Aero club of France’s Archdeacon Prize. The flight was recognized by the French as the first self-propelled heavier-than-air machine to take off in public and was greeted with enormous enthusiasm and coverage in the newspapers.

Then on Nov. 12, the bis-14 was fitted with primitive ailerons and achieved several flights, the longest being 722 feet in the time of 21 seconds at an altitude of 20 feet.

The machine, however, was impractical and Santos-Dumont flew it only one more time.

Octave Chanute wrote to the Wright brothers telling them about Santos-Dumont flights. Wilbur responded in 1906 with the following remarks: “When we see men laboring year after year on points we overcame in a few weeks, we do not believe there is one chance in a hundred that anyone will have a machine of the least practical usefulness within five years.”

In 1910 the Wrights brought suit against Santos-Dumont for infringement on the Wright’s French patents.

Santos-Dumont’s next machine was the 1907 Demoiselle (meaning dragonfly). It was the world’s first light plane. The pilot sat below the wing just to the rear of the engine. The engine powered a two-blade wooden propeller rotating just ahead of the leading edge of the wing.

Flight demonstrations of a replica of this machine were conducted during its stay in Dayton.

Santos-Dumont was born in Brazil on July 20, 1873 to a family made wealthy by the coffee business. He had multiple sclerosis that caused him to retire from flying in 1910. He returned to Brazil and committed suicide on July 23, 1932.

Santos-Dumont was a popular man as an aerial showman even though he contributed little to aeronautical engineering. When the hometown Dayton Herald carried the story of “first flight” on Dec 17, 1903, it carried the headline: Dayton Boys Emulate Great Santos-Dumont. The Herald made the mistake of comparing balloon flights with the first flight of a flying machine.

In 2007 Amanda Wright Lane, great-grandniece of Wilbur and Orville Wright visited with Mario Villares, grandnephew of Santos-Dumont in Brazil. Lane said that she admires Santo-Dumont’s passion for flight. She said that he saw flying in so many ways.