What did they know, and when did they know it?
Long before Watergate made this question trendy, it was
being asked of the two Ohio brothers now acclaimed as the fathers of aviation.
The burden of answering it may have hastened the death of one. It dogged the
other for life.
The issue arose in 1909. The venue was a patent suit. The
defendant, plane-builder Glenn Curtiss, had been hauled into court by Orville
and Wilbur Wright, the Ohioans who six years earlier had invented the airplane.
Or had they?
Curtiss provided cause for doubt. He charged that the
"secret" of the Wrights' invention was, in fact, nothing more than a
basic aeronautic principle. Worse, he alleged that it had been discovered
years before the Wrights embarked on serious aviation careers.
It was a sensational charge, one that did not die there. The
claim haunted the brothers through a long series of lawsuits waged at home and
abroad. Time and again, they were pressed to prove their paternity of the idea
at the core of their invention—an idea that they called
Wing-warping was a novel flight-control system. It entailed
twisting the ends of wings in opposite directions at the same time. With it,
the Wrights' flyer managed to retain balance in air, execute turns on command,
and thus stage, in 1903, the first powered flight.
Not long afterward, the Wrights received patents on
wing-warping. However, Curtiss soon began using the technique in his own
airplanes, employing different mechanical means. The Wrights sued, crying
patent violation. Curtiss responded that, while the brothers could patent their
specific mechanical means of applying the wing-warping principle, they could
not patent the principle itself, particularly since they hadn't discovered it.
With the Wrights maintaining that they had made the
discovery, and Curtiss insisting they had not, resolution of the matter turned
on the question of when, where, and how the Wrights first hit on the basic idea
From the Birds
The simplest answer provided by the Wrights was that they
had learned about it from the birds. Wilbur Wright advanced this claim as early
as the spring of 1900, long before the lawsuit, in his first letter to Octave
Chanute, a French-born glider enthusiast.
Wilbur wrote: "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 wing tip is twisted upward and the left downward the
bird becomes an animated windmill and instantly begins to turn, a line from
its head to its tail being the axis."
Wilbur added that he planned to build an apparatus that
would add this torsion principle to a double-deck glider, one similar to the
type Chanute had used. Wilbur said that he already had tested the idea on a
kite and was sufficiently encouraged to lay plans for a trial using a full-size
Even earlier, in an 1899 letter that Wilbur wrote to the
Smithsonian Institution seeking information about flight, he had mentioned his
habit of observing birds.
Did the Wright brothers really get their idea of
wing-warping from the birds? Perhaps. Years later, however, Orville would
discount the value of such observations. He stated that he could think of
nothing original the brothers had learned in this way.
"Learning the secret of flight from birds is a good
deal like learning the secret of magic from a magician," he explained.
"After you know the trick and know what to look for, you see things that
you did not notice when you did not know exactly what to look for."
For some, this raises the question of whether the Wrights
learned "the trick" from others. In his 1899 Smithsonian letter,
Wilbur mentioned reading a work by Etienne Jules Marey that described the action
of birds' wings. Similar descriptions of the flight of birds are found in
pamphlets provided by the Smithsonian and in books that it suggested to the
Understanding the birds' secret of control was one thing.
Finding a practical means of applying that secret to a man-carrying flyer, however,
was quite another. On this key issue, the Wrights again claimed that they had
worked out a solution independently.
From their reading, the Wrights said, they had learned that
experimenters pursued one of two tracks. One group tried to build stable machines
that could be steered like autos. The other tried to compensate for wind
changes by shifting a pilot's body weight in flight. The "drivers"
found that their machines could remain balanced only in calm air. Their rivals
found that "body English" alone was insufficient for airborne
The Wrights decided to build a hybrid—an unstable machine
equipped with mechanical means of control. The answer was a system to duplicate
the birds' twisting of their wingtip s
After a false start, Wilbur hit on a solution by accident. A
customer had come to the Wrights' bicycle shop to buy an inner tube. Wilbur
pulled one from a pasteboard box. While the two chatted, Wilbur idly twisted
the box in his hands. Suddenly, he realized he was producing the kind of
torsion he wanted.
In 1898, the Wrights tried out the concept in the
double-decker kite Wilbur described to Chanute the following year. The kite
proved the principle. Over the next three years, they built a series of gliders
using the same wing-warping system. When the gliders tended to slew and
sideslip, the Wrights added fixed rear fins. When that failed to work, they
converted the fixed fins into a movable rudder connected to the wing-warping
In 1903, they built a flyable powered machine. Yet it and
two subsequent machines continued to display control problems. It was not
until 1905 that the Wrights separated warping and rudder controls so each could
move independently. Thus was born a machine with the basic ingredients of a
Satisfied that they had perfected a practical craft, the
Wrights stopped flying for more than two and a half years.
During part of the time, they waited for approval of their
patent. They had applied in March 1903, nine months before their historic first
flight. In May 1906, it was granted. Soon, the brothers were seeking customers;
by the summer of 1908, the Wrights were flying once more.
By then, however, they did not have the air to themselves.
Their success had rekindled enthusiasm among experimenters. The rival machines
varied in design, but the successful ones shared a common feature: some means
of changing the trailing edges of the wings so they would work in opposite
The first such machine to arouse the Wrights' concern was
made by Curtiss. A motorcyclist and engine builder, Curtiss had joined the
Aerial Experiment Association. In January 1908, the Wrights gave. AEA
information about their control system on the understanding that it would be
used for experimental work, not for production of commercial machines.
The association built three planes. The last, known as the
June Bug, was designed by Curtiss. The Wrights were miffed when Curtiss used it
to win a trophy from Scientific American Magazine for the first officially
recorded American flight of more than a kilometer. The Wrights themselves had
covered greater distances, at least since 1905, but no official observers had
Soon, Orville was warning Curtiss that the June Bug's use
of movable wing surfaces was covered by the Wrights' patents. He invited
Curtiss to seek a license. Curtiss ignored the warning and, in 1909, formed a
company with Augustus Herring to produce machines for sale. Their first was the
Gold Bug, sold to the Aeronautic Society of New York. They built a second, the
Golden Flyer, for Curtiss to fly in the Gordon Bennett trophy race in Reims,
France. On the eve of the race, the Wrights filed formal patent suits against
the Herring-Curtiss Co., Glenn Curtiss, and the Aeronautic Society of New
None of Curtiss's machines used the Wrights' wing-warping
system. Instead, they had small, movable surfaces mounted between the ends of
the upper and lower wings. As one of these ailerons was raised, that on the
opposite side automatically lowered. The effect of ailerons was the same as
that of wing-warping.
Curtiss did not claim to have invented ailerons. What's
more, the experimenter who did invent them conceded that he had been inspired
by the Wrights' success with wing-warping. Ironically, the man at the heart of
the aileron business was none other than the Wright's old friend and mentor,
Since Wilbur's first letter to Chanute, he and his brother
had kept in touch with the older man. Chanute encouraged them to share their results
with other experimenters. At first, the Wrights did so. As they neared success,
however, they grew more guarded about the information they disclosed.
It was one thing for the Wrights to keep their mouths shut,
but restraining the voluble Chanute was quite another matter. In April 1903,
months before the Wrights' first flight, Chanute gave a brief description of
their wing-warping idea in a speech before France's Aero Club.
The talk was covered by aviation journals, and the next
year, French experimenter Robert Esnault-Pelterie attempted to copy the Wright
glider. Deciding that twisting the wings would weaken its structure, he designed
a system in which the wings would remain rigid and smaller, separate surfaces
would move. He called them "horizontal rudders," but they soon became
known as ailerons (from the French word for wing, aile).
lt-Pelterie's machine didn't work well, but others
picked up on the idea of ailerons in their own aircraft. Among these inventors
When the Wrights sued Curtiss, Chanute vowed to remain
neutral, but he fed the Wrights' opposition its best arguments. In an August
1909 letter to Aeronautics Magazine, Chanute claimed that the Wrights' suit
would not only antagonize many, but might also "disclose some prior
patents which will invalidate their more important claims." Later, Chanute
wrote the editor again, giving specifics. He claimed that, after first making
contact with the Wrights, he provided them with a copy of an 1897 patent
granted Louis-Pierre Mouillard for a system that "clearly covers the
warping of wings."
Chanute had carried on a lengthy correspondence with the
French inventor, giving him encouragement and financial support. When Mouillard
had little success with his control system and showed no interest in seeking a
patent, Chanute himself applied for a US patent on it in Mouillard's name and
his own. It was granted in 1897, a few months before Mouillard died.
Chanute said that he had told the Wrights they were free to
use Mouillard's system because Mouillard was dead and his heirs had made no
claim to it. Years later, Orville said that he did not remember Chanute's offer
and that, in any event, the Wrights had not been interested, having already
developed their own wing-warping controls.
By October 1909, Chanute was talking not only to the press
but to the rival legal camp, suggesting other impediments to the Wrights'
claims. In a formal legal statement on the origins of wing-warping, he wrote:
"The bare idea of warping and twisting the wings is old, but there are
several ways of accomplishing it." He named others besides Mouillard who
had described the principle or actually developed systems for using it.
The Last Straw
The New York World quoted Chanute in a series of articles
questioning the Wrights' claim. The paper suggested that they had gotten most
of their ideas from Chanute himself.
For the Wrights, that was the last straw. Wilbur fired off a
scorching letter to Chanute, reminding him that Chanute had assured them as
early as 1901 that their system was an original.
In his reply, Chanute conceded that the Wrights' system. was
original, but added that "it does not follow that it covers the general
principle of warping or twisting wings; the proposals for doing this being ancient."
Chanute said that he thought he had called the Wrights'
attention to Mouillard's system. "If the courts will decide that the
purpose and results were entirely different and that you were the first to
conceive the twisting of the wings," he said, "so much the better for
you, but my judgment is that you will be restricted to the particular method
by which you do it."
Chanute added, "I am afraid, my friend, that your
usually sound judgment has been warped by the desire for great wealth."
This last barb doubtless was calculated to draw blood. The
Wrights' greatest booster was accusing them of greed. In his first letter to
Chanute, Wilbur had said, "I make no secret of my plans for the reason
that I believe no financial profit will accrue to the inventor of the first
flying machine, and that only those willing to give as well as to receive suggestions
can hope to link their names with the honor of its discovery."
Chanute aired a long-festering grievance. He said that he
resented the impression the Wrights had given that he had thrust himself on
them and had been of no real help in their work.
Wilbur's answer was equally bitter. If Chanute resented
being given too little credit for his contribution, he said, then the brothers
resented his giving the impression that they were no more than his pupils.
"As to inordinate desire for wealth," Wilbur
concluded, "you are the only person acquainted with us who has ever made
such an accusation. We believed that the physical and financial risks which
we took, and the value of the service to the world, justified sufficient compensation
to enable us to live modestly with enough surplus income to permit the
devotion of our future time to scientific experimenting instead of
The rift lasted for months. Finally, Wilbur wrote a
conciliatory note suggesting they mend their friendship and work out a
statement describing Chanute's contribution. Chanute said that he too was
eager to resume good relations. They never worked out the statement, however,
and Chanute died that November at seventy-eight.
A Partial Victory
By then, a New York circuit court had ruled that the
Mouillard system, which turned down one wing-tip at a time, was meant only to
turn the airplane. If Mouillard had tried to use it to maintain balance, the
court said, it would have disturbed the equilibrium rather than restored it. In
any case, the court said, it did not bear on the Wrights' claim.
The victory was partial. It did not involve the case against
Curtiss, but rather an injunction against Louis Paulhan, a French flyer whom
the Wrights had accused of infringing their patents by bringing European
machines into the US for exhibitions. Within a year, however, the Wrights had
won favorable rulings in French courts and were begin-fling to work out royalty
arrangements with European plane makers. "The French decision,"
Orville wrote to a friend, "virtually clinches our case in the American
His prediction was premature. The Curtiss case dragged on.
In 1910, the Wrights offered to end it if Curtiss would take out a license under
their patents and settle for past infringements. Curtiss demurred, and the
Wrights dropped the offer. By late 1911, they had won injunctions against
Curtiss, but no final judgment.
Meanwhile, the Wrights suffered a setback in the German
courts. German law held that disclosure of an invention before application for
a patent invalidates the patent. Again, it was Chanute who had created the
problem. When the court learned of his description of the Wrights' wing-warping
to the French Aero Club, it ruled that it was enough to compromise their
claim. German patents had not been sought until March 1904.
Back in the US, Curtiss appealed the injunction and, by
posting a bond, was able to continue to build planes. By May 1912, Wilbur was
seriously ill with typhoid fever. The long legal ordeal weighed heavily on him.
In a letter to a friend, he complained that competitors already were selling
machines at prices below those the Wrights were asking. If the case dragged on
much longer, he said, others would find new ways of evading their claims, even
in the event of a favorable judgment. Wilbur died a few weeks later. Orville
was convinced that the ordeal of the long court battles had helped to kill him.
Orville continued the patent fight alone and, for a time,
seemed to be winning. In January 1914, a federal appeals court in New York
rendered judgment in the Curtiss case, upholding the Wright patents. But, with
his business threatened, Curtiss tried to skirt the court order by modifying
his control system so that each aileron could be worked independently. Orville
brought another suit, and the whole process began anew.
Curtiss now looked for a new way to discredit the Wrights'
claim. A possibility, he decided, would be to prove that Samuel Langley's
"aerodrome," which did not use wing-warping, could fly. That machine
was designed by Langley while he was Secretary to the Smithsonian Institution.
It had been tested twice, a few weeks before the Wrights' successful flight of
1903. Both times, its wings collapsed before it was airborne. Langley, ridiculed
for his failure, died a few years later. He had been able to fly successful
steam-driven models as early as 1896, however, and supporters still believed
that his full-sized aerodrome would have worked.
Curtiss approached the Smithsonian with the idea of
restoring the Langley machine and attempting a flight. The Institution, eager
to redeem Langley's reputation, agreed.
Curtiss took the machine to his factory at Hammondsport, N.
Y., and not only restored it but rebuilt it. He strengthened the wings, changed
their curvature, added a new control system, and substituted a Curtiss engine
for Langley's original. The aerodrome collapsed again on its first trial, but
Curtiss continued to change it until he was able to coax it into the air for a
few short flights.
Without disclosing the craft's modifications, the
Smithsonian announced that Langley's machine had flown. The aerodrome was returned
to its original condition and displayed at the museum with a sign describing it
as "the first man-carrying aeroplane in the history of the world capable
of sustained free flight." That made Orville so angry that he sent the
original Wright flyer to a British museum, where it remained for years. He
agreed to bring it back only after the Smithsonian removed the sign and admitted
how much the aerodrome had been altered to make it fly.
Whether the aerodrome hoax would have worked for or against
Curtiss in court remains moot. Orville's new suit against Curtiss never came
to a judgment. In 1915, he sold the Wright Co. and patents to New York
capitalists. The new company continued the suit, but Curtiss managed to delay
until 1917, when a cross-licensing agreement eased all patent restrictions to
speed wartime production.
The Wrights had not made a fortune, but Orville did have
enough to live modestly and devote his time to experimenting. He became embroiled
in other suits, most claiming that someone else had flown first or had
developed a control system that predated the Wrights'. None succeeded.
Even today, however, writers plow the old ground, seeking
proof that the Wrights really weren't first. The Wrights may have borrowed more
than they liked to admit and may have given Chanute and others less credit than
they deserved. The fact remains that they were the first to put it all together
A World War II B-24
bombardier, Bruce D. Callander was recalled to active duty during the Korean
War. Between tours of active duty, he earned a B.A. in journalism at the
University of Michigan. In 1952, he joined Air Force Times, becoming Editor in
1972. His most recent article for AIR FORCE Magazine was "Enlisted Pilots"
in the June '89 issue.
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