Chapter 6
Problem Solving To Success
While the printing and bicycle businesses took up much of Wilbur and
Orville's time, they were constantly searching for new projects to
undertake. A new interest began to materialize when Otto Lilienthal's
death in a glider accident captured the brothers' attention in August
1896, and they began to consider pursuing aeronautics. The events
leading up to this began when Wilbur wrote his father that "Orville is
complaining some for a day or two, but is taking quinine and I think
will be all right in a few days." [1]
Wilbur's prediction proved false, and a few days later Orville developed
typhoid fever. Hearing of Orville's sickness, the Bishop responded to
Katharine:
I am sorry that Orville is sick, and sorry that I am away when he
is sick. While I hope it may prove but a mild attack, I have grave
apprehensions that it may prove a severe seigt [sic]. Inform me by mail,
and by telegraph, if the latter is necessary. Put him in the best room
for air and comfort, sponge him off gently & quickly with the least
exposure and follow with mild frictions.
Believing that Orville contracted typhoid from the well water at the
bicycle shop at 22 South Williams Street, Milton further advised
Katharine to let no one else use the water from that well and to boil
and then cool in ice all of the water that they drank. In addition, he
counseled them to be "temperate in articles eaten," as well as being
regular. [2]
The family consulted Dr. Spitler who had treated both Wilbur and
Susan earlier. He had little to recommend; the fever would have to run
its course. Katharine delayed her return to Oberlin College to stay in
Dayton to assist Wilbur in caring for Orville. Milton also cared for his
son after he returned to Dayton on September 4. Orville spent much of
the month of September in delirium, and a trained nurse was hired to
alleviate the burden on the rest of the family. It was not until six
weeks later that Orville was able to sit up in bed and eat some tapioca,
his first solid food. [3]
During Orville's illness, Katharine and Wilbur often read the
newspaper to him. Since Orville was unconscious, this was more often
than not, a way to pass the time while nursing Orville. It was in one of
these times that Wilbur read about Lilienthal's death in a gliding
accident. Lilienthal's experiments had come to the attention of Wilbur
and Orville in July 1890 when the news service they subscribed to for
their paper, The Evening Item, included an article on him. Finding the
information of interest, the Wrights included a short piece on
Lilienthal in their July 26 issue. Then in 1895, a brief newspaper
article on Lilienthal attracted the Wrights' attention, and they
attempted to learn more about his aeronautical experiments. With this in
mind, after Orville's recovery, Wilbur mentioned Lilienthal's death to
him. Always interested in scientific subjects, the Wrights began to
ponder the question of human flight and a possible solution. [4]
To expand their knowledge, the brothers went to the Dayton Public
Library to review books on aviation, and over the next few years Wilbur
and Orville read everything they could find on the subject. It was not
until 1899 that the Wright brothers began actively researching
aeronautics during the off season of the bicycle business. According to
Orville, the brothers' fascination with flight was renewed when they
read a book on ornithology. The book made them wonder why birds could
fly and why man could not fly with something built on a larger scale
which emulated a bird's features. [5]
The first active step Wilbur and Orville took in pursuing the
question of human flight was a letter to the Smithsonian Institution
requesting available information on aeronautical studies. On May 30,
1899, Wilbur wrote requesting papers published by the Smithsonian
Institution or others available in English, for he was, "about to begin
a systematic study of the subject in preparation for practical work to
which I expect to devote what time I can spare from my regular
business." Wilbur further illuminated, "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." [6]
Richard Rathbun, Assistant Secretary of the Smithsonian Institution,
sent a response to Wilbur on June 2. In his letter, Rathbun included a
list of three works related to "aerial navigation" available from the
Smithsonian Institution and enclosed four Smithsonian Institution
reports. The three works available from the Smithsonian Institution were
Progress in Flying Machines by Octave Chanute, Experiments in
Aerodynamics by Samuel P. Langley, and The Aeronautical
Annual for 1895, 1896, and 1897 edited by James Means. The pamphlets
enclosed in Rathbun's response were reprinted from articles originally
published in the Smithsonian Annual Report and included: "Empire
of the Air," by Louis-Pierre Mouillard; "The Problem of Flying and
Practical Experiments in Soaring," by Lilienthal; "The Story of
Experiments in Mechanical Flight," by Langley; and "On Soaring Flight,"
by E.C. Huffaker. Thanking Rathbun for the pamphlets, Wilbur also
ordered a copy of Langley's work which cost one dollar and discussed the
laws governing the resistance of plane surfaces. [7]
LILIENTHAL GLIDING IN ONE OF HIS GLIDERS, USING HIS WEIGHT TO SHIFT THE BALANCE
OF THE GLIDER.
(Courtesy of National Air and Space Museum)
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It is noteworthy that in Wilbur's correspondence with the Smithsonian
Institution he referred only to his own personal interest in aviation.
Nowhere did he refer to his brother Orville, but solely discussed his
own belief that flight was possible. While in later years, the brothers
stated that the initial interest in aviation was a mutual and joint
effort, the idea appears to have been Wilbur's. While Wilbur initially
pursued this new project, Orville soon became an active participant. The
brothers' synergistic partnership over the next few years was one of the
factors that enabled the Wright brothers to successfully complete the
first free, controlled, and sustained flight in a power-driven,
heavier-than-air machine. Two schools of aviation research became
apparent to Wilbur as he reviewed the available material on aeronautical
history and theory. The first was represented by Otto Lilienthal and
Octave Chanute who studied soaring flight. Born in the Pomeranian
village of Anklam on May 24, 1848, Otto Lilienthal and his younger
brother Gustav were fascinated at an early age with the storks native to
the region. By the ages of fourteen and thirteen, respectively, the
brothers constructed an unsuccessful fixed wing glider. The failure did
not deter the brothers, and through the years, they constructed and
experimented with other gliders. [8]
By 1880, Otto was an established engineer who owned a business that
produced engines, boilers, marine signals, and mining equipment. In
addition, he continued his childhood fascination with flight, although
he now attacked the problem with scientific methodology. In 1878,
Lilienthal established a workshop in his home from which he conducted
research on air pressure and lift. Believing serious research was needed
on the principles of flight instead of guesswork guiding the
construction of flying machines, Lilienthal focused his attention on
preliminary research. The result of his research identified the
superiority of a cambered, or curved, wing. In addition, he developed an
air pressure table to assist experimenters in determining the wing area
needed to support a given weight at a particular speed. [9]
With the results of this research, Lilienthal began experimenting
with gliders in 1891. These experiments attracted the attention of
American journalists and led to the widespread publicity that Lilienthal
received in the United States. It was one of the resulting newspaper
articles that attracted the Wright brothers' attention. Lilienthal's
flights ranged in length from 300 to over 750 feet using sixteen
different gliders. In all of these gliders, the pilot was supported
vertically in the center section between the wings. He controlled and
stabilized the glider by swinging his body in different directions to
shift the center of gravity. Lilienthal suffered a fatal accident in
1896 when his glider stalled in mid-air, and he plunged fifty feet to
the ground. He survived until the next day when he died in a German
hospital. [10]
Like Lilienthal, Octave Chanute focused on studying soaring flight.
Chanute was born in France in 1832, and immigrated to the United States
with his parents in 1838. A successful and highly respected civil
engineer, Chanute worked for various railroad companies. He began his
career in Albany, New York, and subsequently moved westward, eventually
settling in Kansas City and then Chicago. During an 1875 trip to Europe,
Chanute discovered that many of his European counterparts considered the
airplane a possibility. The idea captured Chanute's imagination, and he
began taking an interest in aeronautical research. In 1885, Chanute
began conducting a survey of all aviation research and literature. He
compiled his research, in 1891, into a series of articles reporting the
results of aeronautical research and directing a path for future study.
These articles were published in 1894 in a book titled Progress in
Flying Machines. Along with Lilienthal's work, Progress in Flying
Machines became a mandatory source for aviation experimenters. [11]
OCTAVE CHANUTE
(Courtesy of National Air and Space Museum)
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As a result of his survey, Chanute recommended that engineers should
become involved in aeronautical research. He determined that experiments
would greatly benefit from engineering knowledge. In addition, because
he felt that experimentation with gliders was necessary, Chanute
designed and built a number of gliders for testing. Since he was
sixty-four years old when he began experimenting in 1896, Chanute hired
Augustus M. Herring and William Avery to pilot the gliders during the
experiments conducted on the south shore of Lake Michigan, near Chicago.
These two also assisted with glider design. [12]
One of the gliders was a biplane glider that he designed and built
with the assistance of Augustus Herring. The biplane glider's wings were
based on the Pratt-truss system and the pilot was situated by supporting
himself by his arms and hanging below the wing, similar to the
Lilienthal glider. This glider became the most influential aircraft of
the era prior to the Wrights' entry into aeronautics. To date, the
Chanute-Herring biplane glider was the most stable and successful flying
machine built, gliding up to several hundred feet, but they lacked the
essential element of control. This biplane glider design influenced the
form of the Wright brothers' future gliders and airplanes. [13]
The second school of research, represented by Samuel P. Langley,
focused on powered flight. Langley was born in Roxbury, Massachusetts,
in 1834. He first trained as a civil engineer and architectural
draftsman. Eventually he turned his attention to astronomy, and in 1887,
when he was asked to serve as the assistant secretary of the Smithsonian
Institution, Langley was one of the most well-regarded astronomers in
the United States. He became interested in powered flight in 1886 at an
aeronautical lecture in Buffalo. The meeting was held under the auspices
of the American Association for the Advancement of Sciences and had been
arranged by Chanute. By 1896 Langley produced his first successful
model, the steam driven Aerodrome No. 5. Langley named his models
Aerodromes after the Greek term aerodromoi meaning air runners. On May
6, Aerodrome No. 5 flew two flights which unquestionably proved that a
large power-driven model could fly. [14]
After his successful tests with Aerodrome No. 5, Langley intended to
stop his public experiments and let other enthusiasts continue the quest
to achieve flight. But, in 1899, after lobbying efforts by Langley and
his friends, the United States granted Langley $25,000, with the
potential of another $25,000, to build an aerodrome for military
purposes. All of the Langley aerodromes built to fulfill the contract
were based on the concepts used in the successful 1896 machine, for
Langley believed that he only needed to enlarge the earlier model to
successfully carry a man. [15]
Wilbur gave his attention to the former school of research, "partly
from impatience at the wasteful extravagance of mounting delicate and
costly machinery on wings which no one knew how to manage, and partly,
no doubt, from the extraordinary charm and enthusiasm with which the
apostles of soaring flight set forth the beauties of sailing through the
air on fixed wings, deriving the motive power from the wind itself."
Having chosen a research methodology, Wilbur still needed to further
define his experiments and research. [16]
The three general aeronautical research issues were wings to lift the
machine into the air, a power source to propel the machine, and a means
of controlling the machine. The groundwork in the first two areas was
already addressed by Lilienthal, Chanute, and Langley. Wilbur felt the
available equations and data would provide enough information for him to
design his own wings. While he would inevitably encounter further
aerodynamic problems, Wilbur believed the groundwork conducted by other
aeronautical research was a sufficient base from which to start. As for
a power source, Langley's steam engines used to power his Aerodromes
could not run a full-scale model, but they did prove that it was
possible to build an engine that would propel a flying machine into the
air. Wilbur was convinced technology needed to power a full-scale
aircraft would be available when it was needed. This assumption was
based on the amount of research the automobile industry was directing
toward producing a lighter and more powerful internal combustion engine.
[17]
That left the question of controlling an airplane. This was a complex
issue, for an airplane was the first vehicle that required control of
three axes of motion: pitch, roll, and yaw. Pitch, revolving around a
horizontal line running from wing tip to wing tip, moves an airplane's
nose up or down to initiate a climb. Roll, which determines the lateral
altitude of an airplane, revolves around a longitudinal horizontal line
running through the center of an airplane from nose to tail, and is used
when one wing tip is raised and the other lowered. Yaw, revolving around
a vertical line running from top to bottom through the center of the
machine, moves the nose to the right or left in a flat turn and
determines the direction of the flight path. These components are easily
described as the vertical for changing altitude, the lateral for banking
or rolling back to level, and the level or horizontal for turning. In
attempt to control yaw and pitch, basic devices were established by
aeronautical researchers before 1860. Techniques for turning on a level
plane (yaw) by using a form of a ship's rudder were proposed by
balloonists in the eighteenth century, and ideas to alter the rudder to
a horizontal device, called an elevator, were later incorporated to
control the pitch, or rise and descent, of airships. [18]
CAYLEY'S SILVER DISK SHOWING HIS CONCEPTION OF THE ELEMENTS OF AN AIRPLANE.
(Courtesy of National Air and Space Museum)
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In regards to human flight, Sir George Cayley, born in Scarborough,
England, in 1773, reached a critical turning point in the field in terms
of control. In 1799 Cayley proposed an airplane configuration, based on
his research, which was vastly similar to today's airplanes and one of
the most important of his original designs. Inherent in Cayley's design
was the observation that the system of thrust and the system of lift
needed to be separate, meaning that a flying machine needed both fixed
wings and a form of propulsion. Cayley's concept was a break from the
traditional idea that moving wings would propel a man through the air.
This design and the idea of providing separate systems for thrust and
lift was a major step forward in aeronautical research, and many
individuals in following years based their experiments and research on
this concept. This includes Cayley who based the design of his basic
glider model of 1804 on these ideas. The glider, the first modern
configuration airplane, incorporated a fixed plane with an adjustable
rudder and elevator to control both the yaw and pitch. [19]
Alphonse Pénaud also envisioned, independently of Cayley, the use of
a horizontal tail as a means to control longitudinal stability. He was a
French naval engineer who, because of a debilitating hip disease, had
been confined to a wheelchair as a child. In 1871 he built and flew a
small, rubberband-powered, monoplane glider. Pénaud designed the glider
with a dihedral angle in the wings which led to inherent stability by
increasing lift on a wing tipping downward causing the plane to level
again. This work with inherent stability was Pénaud's most important
contribution to aeronautics. As Peter Jakab described, "Pénaud correctly
theorized and demonstrated the fundamentally important concept of
aircraft stability that Cayley exhibited, but did not fully understand,
in his original 1799 conception of the airplane and later gliders." [20]
Roll was another matter. Few experimenters had dealt with this aspect
of control and prior to the Wright brothers there was no concept of
lateral control. Researchers needed to break away from the notion that
machines operated on one plane, or surface, and the need to achieve
inherent stability. If a machine maintained inherent stability, it would
only operate on one plane, moving along a straight and level course
without any involvement from the pilot. There were various explanations
and theories that supported the researchers' quest to achieve inherent
lateral stability. Many were convinced that atmospheric gusts and
currents shifted rapidly thus defeating the ability of human reflexes to
respond, and that what was needed was a stabilizer that could sense
these changes and respond accordingly. In addition, few experiments
focused on a finished airplane with complete control. Most felt that the
first step in human flight was the need to demonstrate a straight flight
with a pilot. [21]
Once he determined that he would focus on soaring flight and a means
of control, Wilbur needed to define how he would conduct experiments. At
the end of the nineteenth century, based on the results of earlier
research, there were three approaches as to the best way to conduct
aeronautical experiments. The first was to start with the construction
of experimental models. The second was the experimentation of full-size
gliders before moving to powered aircraft. The third theory, based on
the advancements of research, argued that there was sufficient existing
research for a full-scale, piloted airplane to be built with little
preceding work. The researchers who contributed to the growing
understanding of aeronautics in this time each adhered to one of these
theories for experimentation. [22]
PENAUD'S 1871 RUBBER-BAND-POWERED MODEL GLIDER.
(Courtesy of National Air and Space Museum)
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Cayley first demonstrated the value of using models for experiments
with his 1804 glider, and this form of experimentation was further pursued
by Pénaud. Cayley also played an important role in defining the
necessity of the use of gliders, the second of the three theories of
aeronautic experimentation. He conducted trials with his first full-size
glider in 1849 and again in
1853 with a different glider. The most famous experimenter who made
flights with unpowered aircraft in the later half of the nineteenth century
was Otto Lilienthal.
Sir Hiram Maxim, an American expatriate living in England who had
achieved fame as the inventor of the machine gun, was one of the most
prominent proponents of the third theory. His research focused on lift
and thrust, not control, and he believed the only significant remainder
in tackling human flight was the invention of the lightweight engine to
power an aircraft. In an effort to prove this, Maxim constructed a large,
four-ton biplane that he equipped with two 180 horsepower steam engines
to each power an eighteen foot propeller. The airplane traveled along
rails, and during a test on July 31, 1894, it lifted several inches from the
rail, broke from the guard rails, and crashed. With this trial, Maxim
showed that with enough power a plane could be lifted into the air for
a brief time, but he proved nothing new. Lacking all essential elements,
except power, needed for a practical flight, his biplane experiment contributed
little to the aeronautical field. [23]
Another experimenter who, like Maxim, constructed full-sized, powered
aircraft with little previous work with models or gliders was Clément
Ader. Ader was a French electrical engineer who was a leader in the
development of the telephone. Interested in aeronautics, Ader built and
attempted to fly a full-size, steam-powered machine he named the Éole.
Like Maxim, Ader gave little thought to controlling his aircraft once it
was airborne. In October, 1890, the Éole made a short hop of 185 feet at
an altitude of eight inches with no stability. While Ader was
technically the first man to leave the ground in a powered flying
machine, he did not achieve free, controlled, and sustained flight. For
this reason, his experiments, while noteworthy, did not influence the
course of aviation. Both Ader and Maxim's aircraft were lifted through
the use of a strong power source, but their experiments demonstrated
that much remained to be done in researching human flight. Their
uncontrollable machines even further proved that there was still much to
be understood regarding aerodynamic problems. [24]
In order to research aerodynamics and control, Wilbur chose to follow
Lilienthal's example and experiment with gliders. The problem with this
form of research was that there was little or no margin for error while
operating a glider. Prior to actual glider experiments, an understanding
of the problem and a potential solution were needed. Following this
method, Wilbur observed birds in order to better understand control.
This was not the first time in his life that Wilbur had observed birds
for answers to the question of flight. Between 1897 and 1899, Wilbur and
Orville often visited The Pinnacles, south of Dayton, to observe the
flight of birds. In 1899, while observing buzzards in flight, Wilbur
noticed that the birds twisted the tips of their wings as they flew
through the air as a means of balancing themselves in roll. [25]
At this time Orville was not an equal partner with Wilbur in his
pursuit of human flight, but he was involved in the project. Often the
brothers would examine the literature detailing the results and theories
discovered by previous experimenters. While Wilbur was the driving force
in the project, Orville often participated in discussions and shared
ideas on aeronautics with his brother. One example of Orville's level of
participation was his suggestion to achieve lateral control. He made a
rough sketch of a wing with a stationary section at the center and two
adjustable sections on either end. By moving a lever attached to the
adjustable sections, one wing section would rotate in one direction
while the other wing would turn in the opposite direction. Inherent in
this design was the problem that the system needed to be strong, but
also light enough for use. [26]
Several weeks later, in July 1899, Wilbur happened upon a workable
solution. Previous aeronautical researchers used dihedral angles on the
wings to maintain a longitudinal axis on a straight flight, for they
erroneously believed that flying an aircraft would be an easy matter of
maneuvering the machine on a level plane of air. Understanding that a
flying machine needed balancing in three-dimensional space, Wilbur
noticed, when observing birds in flight, that soaring birds made subtle
changes in their wings to maintain their lateral equilibrium, and he
became convinced this was the key to solving lateral control. One
evening, while working in the bicycle shop alone, Wilbur sold an
inner-tube to a customer. While speaking with the customer, Wilbur
picked up the inner-tube box and began idly twisting it. He noticed that
as he twisted each end of the box, the top and bottom surfaces remained
parallel but the surfaces at each end were at a different angle. That
was the answer; instead of treating each wing as a separate unit, he
could twist the entire wing structure in either direction to emulate a
bird's wings. [27]
This idea of Wilbur's was the first that increased the lift on one
wing while simultaneously decreasing lift on the other wing as a way to
achieve lateral control. This was to be achieved by incorporating a
complete helical twist along the entire wing structure in either
direction. Based on how the wings twisted to bring one wing to a greater
angle than the other, the Wright brothers named the process wing
warping. A major component of the Wrights' contribution to aviation,
this function is fulfilled by ailerons in modern day airplanes. [28]
When he conceived of wing warping, Wilbur was operating the bicycle
shop while Orville spent the day taking his sister and her friend from
Oberlin College, Harriet Silliman, on a tour of Dayton. Harriet was
visiting Katharine and staying at the Wright home on Hawthorne Street,
and when the three returned home, Wilbur demonstrated his discovery to
Orville. Within days the brothers began constructing a model to test the
wing warping theory. [29]
The Wright brothers decided upon a biplane configuration for the
model based on several facts. First Wilbur's wing warping theory, based
upon the twisting inner-tube box, logically suggested biplane wings.
Also, their review of aeronautical literature revealed the successful
multi-wing designs of various experimenters, the most significant being
the Chanute-Herring biplane glider of 1896. The Pratt-truss system used
on the glider was, as Peter Jakab suggested in his history of the Wright
brothers:
a perfect solution to the dilemma presented by their wing warping
concept of maintaining the structural rigidity of a wing that could at
the same time be easily flexed for lateral control. By removing the
fore-and-aft diagonal wire-bracing of a Chanute-type biplane, but
retaining the span-wise trussing, the airframe would take on precisely
the same characteristics as the cardboard box with its ends
removed.
The wing warping could then be accomplished by pulling on wires
attached to the outer edges of the wings, instead of designing a
mechanism to maneuver the system. [30]
The biplane model convinced Wilbur that his theory of twisting the
wings was possible, and he began to construct a biplane kite with a wing
span of five feet and a chord of thirteen inches. The pine framework of
the kite was covered with fabric sealed with shellac to make it
airtight. The two wings were trussed together with six struts and wires
crisscrossed between the wings from side to side, but not from front to
rear. The kite included a rear elevator that was attached to the middle
of the rear center strut. Wilbur controlled the kite with two sticks,
one held upright in each hand. Four lengths of line attached to the top
and bottom of each leading edge wing tip strut crossed each other as
they ran from the top and bottom of the sticks. By maneuvering the
sticks, the kite could either rise upwards or roll off to one side. The
kite piqued the curiosity of Wilbur's nephew Milton, and on July 7,
Milton stopped by to see the "flying machine" under construction. [31]
On July 24, Orville, Katharine, Harriet, and a few of their friends,
including Katharine's good friend, Agnes Osborn, departed on a
chaperoned camping trip. Wilbur did not join the camping trip, choosing
instead to stay home to operate the bicycle store and test the kite.
Sometime after everyone departed for the camping trip, Wilbur flew the
kite at Chadwick's hill, a field near Summit and West First Streets.
This was a popular kite flying field for school boys and one of them,
Frederick W. Fansher, remembered in later years one of the Wright
brothers appearing with a peculiar looking box kite. Finding the kite
unique, the boys quit flying their own kites to watch Wilbur's
experiment which was successful. On Sunday, August 6, Wilbur visited the
camp and reported the results of the kite to Orville. [32]
As Orville remembered, Wilbur found, "It responded promptly to the
warping of the surfaces, always lifting the wing that had the larger
angle.... We felt that the model had demonstrated the efficiency of our
system of control." The performance of the kite demonstrated that the
wing warping system was more successful than any of the other control
methods employed by other aviation researchers. The only question
remaining was whether it would work in a full-sized model. Based on the
success of the kite, the brothers decided to take the next step in their
research and construct a full-scale glider. [33]
While committed to continuing their experiments, the Wright brothers
were forced to delay any actions for several months. Through the fall of
1899 and winter of 1900, the brothers were busy assembling their next
year's stock of Wright bicycles. During this period, Wilbur made the
time to search for a location for the planned glider experiments. On
November 27, 1899, he wrote to the Instrument Division of the U.S.
Weather Bureau requesting "if possible a report of the wind velocities
of Chicago or vicinity for the months of August, Sept., Oct., and
November." One of his main criteria for a testing ground was a minimum
wind speed of fifteen to twenty miles per hour. The response from the
U.S. Weather Bureau included a report for August and September that
included average hourly wind velocities at all weather stations in the
United States. [34]
While the records from the U.S. Weather Bureau showed that Chicago
was the windiest city, Wilbur had already rejected that location. The
vast publicity paid to Chanute's experiments in 1896 confirmed to Wilbur
that he needed a remote site. Reviewing the report, Wilbur discovered
that the sixth highest average wind in the United States was recorded at
Kitty Hawk, North Carolina. While he had never heard of the town, Wilbur
decided that its merits as a testing ground warranted further
investigation. [35]
With his busy schedule readying the bicycle shop for the spring,
Wilbur did not immediately respond to the data he received from the U.S.
Weather Bureau. It was not until May 1900, that Wilbur began to make
preparations for his planned experiments. His first act was to write
Octave Chanute. In his letter, Wilbur wrote, "For some years I have been
afflicted with the belief that flight is possible to man. My disease has
increased in severity and I feel that it will soon cost me an increased
amount of money if not my life." He went on to explain his beliefs as to
why flight was possible and his ideas for glider experiments. Wilbur
planned to erect a tower from which to test a man carrying kite, and he
welcomed Chanute's thoughts on the system. Wilbur concluded by asking if
Chanute could recommend a location for experiments between September and
January, for those were the months that Wilbur would be able to leave
the bicycle business. [36]
Chanute's response on May 17 set in motion a correspondence between
the two that would last until Chanute's death in 1910. Chanute became
both a mentor and a friend to the Wright brothers, and he offered
guidance to the Wright brothers throughout their experiments. In his
response, Chanute relayed to Wilbur that he believed his idea for a
tower would be hindered by the necessary restraining ropes which often
created hazards. Chanute himself preferred "preliminary learning on a
sand hill and trying ambitious feats over water." As for suitable
locations to conduct his experiments, Chanute recommended San Diego,
California, and St. James City, Florida. While these two sites had
sufficient steady winds, they lacked "sand hills." Maybe, Chanute felt,
better locations could be found along the coasts of South Carolina or
Georgia. [37]
After receiving Chanute's advice about potential testing grounds,
Wilbur wrote to the U.S. Weather Bureau office at Kitty Hawk, which the
report from the U.S. Weather Bureau showed had sufficient wind. Joseph
J. Dosher, the only bureau employee there, sent a short response
describing the beach near his station as a mile wide and clear of any
obstructions. The winds in September and October blew from the north and
northeast. While Wilbur could board in the village, housing would be a
problem. Dosher suggested that Wilbur would need to bring a tent and
camp. [38]
In addition, Dosher passed Wilbur's letter onto William J. Tate. Tate
responded further to Wilbur's inquiry and highlighted the virtues of
Kitty Hawk for aeronautical experimenters. Tate closed his letter with
the assurance that he would do anything needed by Wilbur to facilitate
his experiments. With Tate's generosity and friendliness along with the
prerequisite constant winds, Wilbur chose Kitty Hawk as the site for his
experiments. [39]
THE WRIGHT CYCLE COMPANY, 1127 WEST THIRD STREET.
(Courtesy of Dayton and Montgomery County Public Library)
|
With the location selected, Wilbur began to construct a glider. This
work, as with the earlier kite, took place in the upstairs of the
bicycle shop at 1127 West Third Street. On August 10, Wilbur informed
Chanute that it was his intention "to begin shortly the construction of
a fullsize glider. Hitherto I have used pine in the frames, but for the
large machine I wish to use spruce, a wood not obtainable in Dayton
yards." In response, Chanute informed Wilbur of the Keith Lumber Company
in Chicago, but he believed that Wilbur could also purchase spruce in
Cincinnati. Instead of continuing to search for spruce, Wilbur decided
to take a chance that he would be able to purchase spruce for the spars
in Norfolk, Virginia. At home in Dayton, he cut, steamed, and shaped ash
ribs for the wings along with approximately fifty additional pieces for
the glider. He also obtained parts not available in Kitty Hawk such as
metal fasteners and steel wire for trussing the wings. Wilbur also cut
and sewed yards of sateen fabric to cover the finished wings. The
remainder of the construction and assembly occurred in Kitty Hawk. [40]
With the preparations complete, Wilbur could no longer delay
informing his father, who was away from Dayton on church business, of
his plans. On September 3, a day before he planned to leave for Kitty
Hawk, Wilbur sent Milton a letter explaining his intent to experiment
with the glider:
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 a
slight possibility of achieving fame and fortune from it. It is almost
the only great problem which has not been pursued by a multitude of
investigators, and therefore carried to a point where further progress
is very difficult. I am certain I can reach a point much in advance of
any previous workers in this field even if complete success is not
attained just at the present. At any rate I shall have an outing of
several weeks and see a part of the world I have not before visited.
[41]
Two days later Katharine informed Milton that she, Orville, and
Wilbur were in "an uproar getting Will off." [42]
If the bishop had any fears as to Wilbur's experiments, Katharine
attempted to alleviate them by mentioning that she did not "think he
will be reckless." In her opinion, the trip would be good for him. She
also shared the information that, if it could be arranged, Orville
planned to join Wilbur in Kitty Hawk after the glider was assembled.
Katharine remembered, in later years, that after hearing the initial
news of his son's pursuit, Milton was always supportive of Wilbur and
Orville's experiments. [43]
As tentatively planned, Orville left on September 24 to join Wilbur
in Kitty Hawk. At this point, Orville became an equal partner in the
aeronautical experiments. No longer did Wilbur dominate the project.
Orville hired Harry Dillon for $4.50 per week to mind the bicycle shop
while the brothers were in Kitty Hawk. Their other employee, Cord Ruse,
continued to come in as needed for bicycle repair work, while Lorin and
Katharine managed the shop and balanced the accounts. This arrangement
did not work long, for on October 13 Orville received a telegram from
Katharine announcing the dismissal of Dillon. Orville was not surprised,
mentioning that he did not expect Dillon would do and that the shop
would have to make due with only Ruse. While they were gone, if
Katharine needed sundries for the bicycle shop, Orville informed her
that a catalog from E.H. Hall Company in Rochester, New York, was in the
store. If anything was needed immediately, Forrer & Scherffer, 22
East Second Street, offered reasonable prices to the Wright brothers.
[44]
Wilbur and Orville remained in Kitty Hawk less than one month. The
newly assembled biplane glider had a wing span of seventeen feet, five
inches, with a five-foot chord and a wing camber of 1 in 23. The total
surface measured roughly 177 feet, including twelve square feet for the
forward rudder, or elevator. The forward rudder was a horizontal surface
mounted in front of the wings, and it was designed to keep the wing's
center of lifting pressure and the glider's center of gravity balanced.
The Wrights' solution, based on the work of Alphonse Pénaud, was the use
of a rudder placed ahead of the wing, known as a canard configuration.
The pilot would lie prone on the bottom wing in order to decrease drag.
The Wright brothers' first glider was the most advanced heavier-than-air
flying machine created to that time, and it was based on their knowledge
of previous experimenters' work and their understanding of aerodynamics
and control. [45]
During their experiments at Kitty Hawk, the brothers flew the glider
both as a kite and as a man-carrying glider with Wilbur as the sole
pilot during the manned experiments. Testing the glider was often
frustrating. During the trials, the brothers discovered that stronger
winds than they had calculated were needed to lift the glider, and even
stronger winds were needed to lift the glider and a pilot. Since winds
of this strength were not plentiful, the Wrights were forced to operate
the glider as a kite for most of their experiments. On the few occasions
when the brothers conducted experiments with a man aboard the glider,
they were content with their system of control. To their delight, they
discovered that the elevator maintained balance while the wing warping
system made five to ten-second glides possible. While in Kitty Hawk, the
brothers only flew the machine with a man aboard for barely ten minutes
and had less than two minutes of actual gliding time. [46]
When they flew the glider as a kite, Wilbur and Orville carefully
measured the lift and drag generated by the glider, the velocity of the
wind, and the angles of the ropes that held the machine. The
measurements indicated that the drag was much less than they anticipated
and the same with the lift. In constructing the 1900 glider, the Wright
brothers used the data recorded by Lilienthal and the standard lift
equations. But the actual results were disappointingly far from the
calculations. The glider should have been able to lift its own weight
and a pilot in winds of about twentyone miles per hour with an angle of
attack of three degrees. The actual performance needed winds of over
twenty-five miles per hour and an angle of attack of almost twenty
degrees. These results caused Wilbur and Orville to begin questioning
the data they relied upon to design their glider. [47]
In addition to raising some disturbing problems, the 1900 experiments
yielded some positive information for the Wright brothers' further
research on human flight. First and foremost, they discovered that their
system of longitudinal and lateral control was a success. The full-size
glider confirmed the success of the wing warping system demonstrated on
the 1899 kite. In addition, the moveable forward rudder performed as he
brothers hoped by limiting the travel of the center of pressure and
allowing the pilot to control the aircraft in pitch. While the short
glides produced sufficient information for Wilbur and Orville to analyze
their control system, they also reinforced the brothers' belief that
they had to practice flying to better understand aeronautics. [48]
While Wilbur and Orville were in Kitty Hawk, Katharine remained in
Dayton. The brothers' trip coincided with the beginning of the school
year, and Katharine was a teacher at Steele High School. Katharine began
teaching at the school in 1899, and in 1900 she taught all of the Latin
classes. These included two beginning, one second year, and two classes
from the previous year. A former student of Katharine's, Samuel Finn,
remembered that, when he or another student did not have his lessons
prepared, one of them would "raise his hand and ask her whether she
thought that powered flight was practical. And she became so enthused
that she would talk the rest of the period and consequently we did not
have to recite." [49]
In the beginning of 1900, fourteen year old Carrie Kayler was hired
to assist with the household work since teaching took up most of
Katharine's time. Carrie had previously worked for Lorin's family after
their daughter Leontine was born in 1898. Feeling that Carrie still
needed training and guidance, Katharine still focused much of her
attention on household matters. By October 1901, Katharine reported to
her father that, "Carrie has improved a good bit under my constant
superintendence." When her two brothers and father were out of town in
the fall of 1900, Katharine opted to stay with her friend, Agnes Osborn.
Since no one was living in the house at 7 Hawthorne Street, Carrie
assisted Netta, Lorin's wife. As soon as Milton returned to Dayton, both
Katharine and Carrie returned to 7 Hawthorne Street. [50]
The brothers departed Kitty Hawk on October 23, and immediately upon
their return to Dayton, Wilbur wrote Chanute to inform him of the
experiments. In his response, Chanute asked for Wilbur's permission to
include information on their experiments in an article he was preparing
for Cassier's Magazine. Wilbur responded, "It is not our intent to make
a close secret of our machine, but at the same time, inasmuch as we have
not yet had opportunity to test the full possibilities of our methods,
we wish to be the first to give them such test," but he did provide
Chanute with several paragraphs of information that he could include in
the article. Wilbur also spent some time in the winter of 1900-1901
drafting articles for publication. The two articles he prepared were
published in July 1901. "The Angle of Incidence" appeared in the
Aeronautical Journal and "The Horizontal Position During Guiding Flight"
was published by Illustrierte Aeronautische Mitteilungen, the
aeronautical journal in Germany. [51]
Based upon the success of the 1900 glider, the brothers began
constructing a larger glider for a 1901 trip to Kitty Hawk to conduct
further experiments. With the results of their 1900 glider tests, the
Wright brothers reached the point where their work was no longer based
on the results of others' research, and any progress would be the result
of their own work and experiments. In preparing for their 1901 trials,
foremost in their minds was how to accurately determine wind velocity
needed to analyze the gliders' performance. Wilbur asked Chanute for
advice on an anemometer, an instrument used for measuring wind force and
speed, for field use. Chanute responded that he owned two, and the
brothers could borrow one. Since the brothers had already expended the
amount they budgeted for the 1901 experiments, Wilbur informed Chanute
that he and Orville would most likely take Chanute up on his offer. He
also extended an invitation for Chanute to visit their camp at Kitty
Hawk. While Chanute did not mention a visit to Kitty Hawk in his
following letter, he did notify Wilbur that he might be able to stop in
Dayton to visit during one of his trips east. What day would be the best
to meet with the brothers? [52]
Wilbur's response to Chanute's inquiry illustrated much about the
Wright brothers' schedule:
During the months of March, April, May, and June our time is very
closely occupied, as our business requires our attention from twelve to
fourteen hours daily. After July 4th the tension is considerably relaxed
and after September 1st we are almost free for four months. If your trip
falls within the months of May or June, we could make your visit much
more pleasant and satisfactory if you could arrange to stop off and
spend Sunday with us at our home. We are entirely free all day Sunday.
We would make most of a visit at any time but during the busy season
would be more or less liable to interruptions on business days. [53]
Chanute arrived in Dayton on Wednesday, June 26. The only record of
this meeting was relayed by Carrie Kayler Grumbach in later years.
Katharine left instructions with Carrie to serve melon for dessert.
While preparing the melon, if Carrie found one melon to be better than
the others, she was to serve Chanute a piece from that one. As she cut
the melons, Carrie discovered one was barely ripe and not fit for
consumption. She decided to serve smaller pieces of the preferable melon
to all the guests. Katharine disagreed with Carrie's decision and for a
while Carrie wondered if she would ever be forgiven. [54]
Despite Wilbur's warning that a weekday meeting would most likely be
interrupted by the bicycle business, the meeting with Chanute went
smoothly and without interruptions. This was due to the fact that the
Wright brothers had hired Charles E. Taylor on June 15, 1901, to assist
at the shop, and they were now able to get away from the store for short
periods of time, leaving the store under Charlie's supervision. Charlie
Taylor was a thirty-three year old machinist, and his wife, Henrietta
Webbert, was the sister of Charles Webbert, the Wright's landlord. The
Taylor family moved from Kearney, Nebraska, to Dayton in 1894, and
Charlie worked at Stoddard Manufacturing for a short time before opening
a machine shop that was located five blocks from the Wright brothers'
bicycle shop. [55]
Charles Webbert introduced the Wrights to Taylor when he owned the
machine shop, and they hired him for work they could not complete
themselves. Two of the projects that Taylor assisted the Wright brothers
with were the development of the oil retaining wheel hub they designed
for the Wright bicycles as well as the original coaster brakes for the
Van Cleve bicycles. Charlie later sold the shop and began working for
the Dayton Electric Company as a supervisor, but he found that he missed
working with tools. Wilbur and Orville offered him a job at the bicycle
shop for thirty cents an hour or eighteen dollars a week. This was five
cents more per hour than he earned at the electric company, and he
gladly accepted their offer. [56]
The bicycle shop was open from Monday through Saturday and closed on
Sundays. It stayed open late on Saturday nights, so the Wrights could
take care of their customers who worked all week and were unable to get
to the shop until the end of their work week. When Charlie began working
for the Wrights, he would open the shop each day at seven in the
morning. The brothers would arrive sometime between eight and nine
o'clock. All three of them would go home for lunch, but at different
times so the store was never closed. The workday ended at six o'clock
when the shop closed. [57]
The Wrights were often busy pursuing their aeronautical research, and
Charlie saw to the customers and bicycle repairs. The brothers spent
much of their time working upstairs in the bicycle shop where there was
a small office and a workroom. Charlie worked in the workroom located in
the back room on the first floor. [58]
As with their 1900 glider, the Wrights designed and constructed the
parts for their 1901 glider prior to departing for Kitty Hawk. In a
letter to Chanute in May 1901, the brothers stated the glider would "be
built on exactly the same general plan as our last year's machine but
will be larger and of improved construction in its details." This
statement illustrates an important component of the Wrights'
aeronautical research. Unlike earlier experimenters, the Wright brothers
used each glider as a starting point for their next. Previous
aeronautical researchers switched between various designs, never being
consistent and building upon their previous work. Wilbur and Orville
started with the design of the 1899 kite and built upon that for the
1900 glider, and then used the information to design the 1901 glider.
[59]
The 1901 glider had twice the lifting surface of their previous
glider, and was the largest glider anyone ever attempted to fly. The
increased size was intended to improve the lift capability, a problem
that they faced during their first year of experiments. A biplane
design, the glider had a span of twenty-two feet and a seven-foot chord
with a total wind area of 290 square feet, an increase from the 165
square foot glider of the previous year. The wing camber was increased
from the 1 in 23 used in the 1900 glider to 1 in 12. The front rudder
was eighteen square feet, and the total weight of the glider was
ninety-eight pounds. [60]
When Wilbur and Orville left for Kitty Hawk on July 7, they left
Charlie in charge of the bicycle shop. With a dependable and trusted
employee to oversee their business, the brothers were able to leave
during the busy season, several months earlier than they originally
planned. This year while the brothers experimented with their glider at
Kitty Hawk, they had several visitors at their camp. Chanute visited the
camp from August 4 through 11, and he also recommended two others to
assist the Wrights. Edward C. Huffacker, who was building a glider for
Chanute, arrived in Kitty Hawk on July 18 and stayed until August 18.
George A. Spratt arrived on July 25 and stayed until August 16. Chanute
recommended Spratt to the Wright brothers because of his interest in
aeronautics and his medical training which would be advantageous in the
remote area where the Wrights were experimenting. [61]
While in Kitty Hawk, the Wright brothers conducted between fifty and
one hundred glides and kite tests with their new glider. The glides
ranged in distance from twenty feet to almost 400 feet, many measuring
more than 300 feet in length. At first, Wilbur, who completed all the
flying, experienced problems with the glider. After several trials where
the pilot kept moving to the rear of the wing, Wilbur finally completed
an undulating flight of around 300 feet. The cause of the problem was
the thin ribs between the spars that were flexible enough to bow at
midpoint causing the center of pressure to move and nose the aircraft
into the ground. As soon as the brothers reduced the camber and
flexibility of the ribs, the glider's performance improved.
With the glider's improved performance, Wilbur attempted to use the
wing warping system to make an intentional turn. When he began the turn,
the glider operated as he predicted, but halfway into the turn the
glider unexpectedly reversed direction. Caught unaware by this
occurrence, Wilbur immediately straightened the glider and landed. This
experience was Wilbur's first with what is now referred to as adverse
yaw, and, as Wilbur discovered, this occurs when the different drag
forces on the two wings cause the aircraft to turn in the opposite
direction intended. This new problem increased the Wrights' frustration
with the glider. After solving the initial problem with pitch, now the
lateral control system did not reliably function. [62]
While the witnesses were impressed with the glider, Wilbur and
Orville were disappointed. As with the 1900 glider, the 1901 glider did
not perform as well as their calculations indicated it should, and the
performance of the glider seemed to create more questions than it
solved. The poor performance of lift reaffirmed the Wright brothers'
suspicions that the lift tables they used to construct the machine were
incorrect. While on the way home from Kitty Hawk, Wilbur reflected on
all the questions raised during the 1901 trials and the remaining work
needed to achieve human flight and predicted that man would never fly in
the brothers' lifetimes. [63]
After returning to Dayton, Wilbur received a request from Chanute to
present a paper on the brothers' experiments at the Western Society of
Engineers meeting in Chicago on September 18. Katharine shared with her
father that, "Will was about to refuse but I nagged him into going. He
will get acquainted with some scientific men and it may do him a lot of
good." Finally accepting Chanute's offer, the family had quite "a picnic
getting Will off to Chicago. Orv offered all his clothes so off went
'Ullam' arrayed in Orv's shirt, collars, cuffs, cuff-links, and
over-coat. We discovered that to some extent 'clothes do make the man'
for you never saw Will look so 'swell'." [64]
While Wilbur and Orville focused most of their attention on
aeronautical research and experiments, Milton was once again becoming
involved in a church controversy. The problem began in 1893 when Milton
resigned as the Old Constitution publishing agent to focus more of his
attention on the legal matters in regards to the disposition of the
church property between the Radical and Liberal branches of the church.
In order to keep the business in the family, Milton nominated Wilbur as
his successor. How-ever, in the election Wilbur lost to Millard F.
Keiter, a preacher in the Old Constitution.
Keiter served as the publishing agent from 1893 to 1901, and he was
confident of being reelected in the April 1901 election. A month prior
to that election, George D. Crane, an accountant from Fort Wayne,
Indiana, appeared in Dayton to audit the account books of the publishing
house. The publishing board, led by Milton, questioned a number of
Keiter's business affairs and transactions, and they instigated Crane's
audit. Milton's fears were confirmed when the audit disclosed a shortage
of almost $6,800 in the accounts. At the General Conference in April,
Keiter was removed from office and succeeded by W.H. Clay. Since a
consensus could not be reached at the General Conference, a special
committee of five was appointed to investigate the matter. [65]
1901 GLIDER BEING LAUNCHED IN KITTY HAWK, NORTH CAROLINA.
(Courtesy of Wright State University, Special Collections and Archives)
|
While the Wright brothers supported their father in "the publishing
house controversy," they also focused much of their spare time on the
flying machine. Katharine reported to her father, "We don't hear
anything but flying machine and engine from morning till night. I'll be
glad when school begins so I can escape." The one exception to flying
machine research that attracted the brothers' attention was the
construction of a one-cylinder illuminating gas engine, mentioned by
Katharine, for use in the bicycle shop. Wilbur and Orville planned to
power their newly purchased drill press and band saw using an overhead
line shaft powered by an engine. Instead of purchasing an engine, the
Wright brothers decided to build one. With the assistance of Charlie
Taylor, who had a minimal knowledge of engines, the brothers set to
work. Katharine reported to her father in October, "Orv's engine is
being made and, as usual, he is very enthusiastic over it. I hope he can
make it go." Katharine's concern was moot; the engine was successful.
[66]
After returning to Dayton, based on the performance of their 1901
glider, Wilbur and Orville began questioning the lift and drag data they
drew from Lilienthal's published work. "We had taken up aëronautics
merely as a sport," Orville reported. "[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." The first step in proving their
theory that the formulas for calculating lift and drag were incorrect
was to actually confirm there was an error. [67]
Lilienthal's tables included the lift and drag coefficients for the
specific wing shape that he used on his gliders. Inherent in the formula
Lilienthal used to determine these coefficients was Smeaton's
coefficient. John Smeaton was a mid-eighteenth century British engineer
who determined that the general relationship of pressure and velocity to
air was a constant 0.005, known as Smeaton's coefficient. This figure
became a standard value that was used without question for nearly 150
years. While the brothers considered the possibility of an error in
Lilienthal's figures, one explanation, they concluded, was that the
widely accepted Smeaton's coefficient was in error. [68]
Wilbur and Orville designed a mechanical analogue for Lilienthal's
tables to prove that a problem existed. Peter Jakab, in his study of the
brothers' process of invention, described the theory behind the
test:
They would first record the actual angle of attack at which the
lift of the curved surface balanced the opposing pressure generated by
the wind hitting the flat plat. They would then calculate what that
angle should be based on the values in Lilienthal's table. From a
comparison of the two results the Wrights would be able to evaluate the
accuracy of Lilienthal's coefficients. [69]
To do this, the brothers recreated the situation represented in the
tables by mounting a bicycle wheel on its side with a cambered
Lilienthal airfoil fixed to the front of the rim.
If Lilienthal was correct, the wheel would remain stationery when
placed in a strong wind. If he was wrong, the air pressure would cause
the wheel to turn. When they could not get enough wind to turn the
wheel, the Wrights mounted the apparatus horizontally over the
handlebars of a bicycle and rode furiously up and down the street. The
wind caused the wheel to turn, proving an error existed in Lilienthal's
coefficients. But was this error in Lilienthal's work or Smeaton's
coefficient as they predicted? [70]
To verify the results, Wilbur and Orville constructed their first
wind tunnel. Invented by Francis Herbert Wenham and John Browning in
1871, the wind tunnel provided an atmosphere to test reactions of
objects to an artificially induced flow of air. This invention provided
a new means to study aerodynamic wing design, but early wind tunnel
experiments produced little useable aerodynamic information. What data
they yielded on flat and curved wing surfaces was not used, for there
was little knowledge how to apply this information in designing flying
machines. The Wright brothers were the first to use a wind tunnel "to
systematically collect specific data on a wide range of prospective wing
shapes to be used in conjunction with the established lift and drag
equations." In fact, they were the first to use a wind tunnel to obtain
information in a form that could be assimilated into the design of an
airplane. [71]
The Wrights' wind tunnel was of simple construction, consisting of a
wooden trough with a small fan at one end driven by the overhead shaft
used to power the equipment in the bicycle shop. The wind tunnel
measured eighteen inches long and had a glass window on the top to
observe the interior during the tests. Wilbur and Orville placed what
they called a balancing vane inside the wind tunnel for the test. The
balancing vane consisted of a vertical rod with two surfaces, one curved
and one flat, mounted on it. Similar in theory to their test using the
bicycle, this test was more precise. The results confirmed the results
of the first test and the existence of an error in the tables. [72]
After identifying the error, nothing was left for the brothers except
to systematically check all of the coefficients in the Lilienthal table.
First, they decided to take a closer look at Smeaton's coefficient. By
comparing figures for the coefficient published by the U.S. Weather
Bureau with their own estimates based on their gliding experiments, the
Wrights determined that 0.0033 instead of 0.005 should be used as the
coefficient used in the formula to determine lift and drag. [73]
By mid-October 1901, Wilbur and Orville finished their second wind
tunnel. Larger than the first, the second wind tunnel was six feet long,
sixteen inches square on the inside, and had a glass viewing window on
the top. A metal hood at one end shielded a two-blade fan that was
driven at a speed of 4,000 rpm. The brothers planned to use the wind
tunnel to test models of wings at every angle of attack. As Peter Jakab
described, "they were designed to measure values related to the actual
aerodynamic forces acting on the model surface in terms that could be
substituted directly into the equation [for lift and drag]." For wings,
Wilbur and Orville used a variety of shapes and sizes to determine the
most efficient lifting surface. The Wrights also constructed three metal
balances designed to balance lift against drag during the tests. The
wing models and balances were constructed of bicycle spokes and hacksaw
blades, and they enabled the brothers to measure what was occurring as
the wind flowed around the wing models placed on the balance. In his
first involvement in the Wright brothers' aeronautical experiments,
Charlie Taylor ground down some old hacksaw blades for the brothers to
use to create the wing models. [74]
Wilbur and Orville began testing thirty-eight model surfaces to
determine specific information regarding wing design. For instance, how
far apart should the wings be on a biplane? Should the upper and lower
wings on a biplane have the same camber? Were two or three wings better?
These experiments lasted for approximately three weeks during the month
of December. Using the results for the wind tunnel tests along with
measurements for lift, drag, and velocity that they made with their
gliders at Kitty Hawk, Wilbur and Orville ultimately created the correct
information needed for the lift and drag of various wing shapes.
According to Wright biographer Fred Howard, these tests were the most
beneficial aeronautical experiments ever conducted with so few materials
and at such a low expense. [75]
While the Wright brothers focused on their aeronautical research,
another significant event of the year was the continuation of their
father's involvement in the Keiter Affair. The hearing recommended by
the General Conference in regards to Milton's claims against Keiter was
held in February 1902. At that time, Keiter convinced four of the seven
board members that the accountant was in error and that any mistakes
were the result of carelessness rather than an attempt to defraud the
church. Milton was one of the three board members who did not accept
this explanation, and he asked Wilbur to look at the books.
While Wilbur was not an accountant or a bookkeeper, he was meticulous
and had experience keeping the books of his and Orville's businesses. In
his review, Wilbur compared the books with the annual reports of the
printing house, and he discovered there were failures to report receipts
and many other errors. Specifically, Wilbur uncovered that Keiter used
some of the funds to purchase personal clothing, pay his own insurance
premiums, and buy construction materials for his own home.
As in the controversy that resulted in the split of the Church of the
United Brethren in Christ, Milton launched a campaign against Keiter by
outlining his arguments in pamphlets. Wilbur, as before, assisted his
father in compiling three pamphlets, and much of Wilbur's spare time was
spent on these projects. One of the reports included a detailed report
of Wilbur's findings in the account books. Wilbur's involvement in the
controversy dictated that further aeronautics would have to wait until
his father no longer needed his support. [76]
The importance of family to the brothers was illustrated by the fact
the even though they were too busy with their bicycle business and
assisting their father to continue their aeronautical experiments,
Wilbur and Orville still had time to visit with Lorin's family and
entertain their nieces and nephews. In addition to sharing Sunday dinner
at 7 Hawthorne Street, the family members often saw each other during
the week. In October, Ivonette and Milton were invited to a birthday
party, and Leontine felt left out of the festivities. In order to
appease her, Orville shared some candy with her and created a party all
her own on his lap. [77]
In adulthood, Ivonette shared fond memories of her two famous uncles
from this time period:
Orville never seemed to tire of playing with us. If he ran out of
games he would make candy. If he happened to be busy with something
else, he would make caramel, which was easier to make and the kind
children couldn't eat fast. If he had time, he made fudge with a long
thermometer to test how long it should be boiled.
Ivonette remembered that Wilbur also enjoyed playing with the
children, although not for as long as Uncle Orv. If Wilbur was tired of
visiting with whichever niece or nephew was sitting on his lap, "he
would straighten out his long legs and we would slide off. That was a
signal for us to find something else to do." Sometimes during evening
visits, Wilbur and Orville would entertain Lorin's children with a
shadowgraph show. There were always two characters who were portrayed:
Sam Bonebrake, who was tall and thin, and Jim Higgenbottom, who was
short and fat and had a high squeaky voice. The brothers would spend
hours at the bicycle shop constructing the metal figures for the show.
[78]
One of the holidays that the Wright brothers' nieces and nephews
fondly remembered was Valentine's Day. Lorin's children would make
Valentine's Day cards for their relatives who lived at 7 Hawthorne
Street. Then they would quietly sneak onto the porch to drop off the
cards, and then stomp away loudly. The stomping would attract the
attention of those inside, so they would come out onto the porch and
find the cards. Leontine recalled:
Uncle Orville couldn't restrain himself from adding to the
excitement of this occasion. Maybe he just guessed when we were coming
but I think my father was in on the game and somehow let it be known
that we were on our way. No matter how well laid our plans Uncle Orville
would burst out of the door just as we were making our escape.
While Leontine and Lorin's other children devised many ideas to
prevent their Uncle from seeing them, there were only a few times that
they were successful. [79]
Visits to 7 Hawthorne Street were not without discipline. When the
children needed punishing, their grandfather Milton would lock them in a
closet under the stairs until they were ready to behave. This punishment
was not as severe as it sounds, for the closet had a window and was
stocked with books and magazines. In another method, according to
Ivonette, "He would put us on the floor, turn a chair over us, then sit
on it so we couldn't get up. When he thought our dignity had a jolt, he
would let us out." Good table manners were essential, and if Lorin and
Netta were not with them, the children's bad manners were corrected with
the statement, "I believe we have a Goop with us today." This comment
was based on The Goop Tales, Alphabetically Told, by Gelett
Burgess which humorously described the various faults good children
should avoid. [80]
While the Wright family continued life as normal, Wilbur and Orville
continued to puzzle over their flying machine. Despite the successful
data obtained from their wind tunnel experiments and the brothers
confidence in the results, Wilbur and Orville chose not to construct a
powered machine in 1902 but another glider. One of their reasons for
building a glider was the need to solve the lateral control problems, or
adverse yaw, Wilbur experienced in the 1901 glider. The completed 1902
glider had a slightly larger surface than the 1901 glider, with a wing
area of 305 square feet. Wilbur and Orville started with the design of
the 1901 glider and incorporated the results from their wind tunnel
tests. The tests indicated that the most efficient wing for adequate
lift would be a camber between 1/24 and 1/30, depending upon how the
wings were rigged, with a five foot chord. The wings on the 1902 glider
had a thirty-two foot wingspan compared to the twenty-two feet of the
1901 glider. In addition, to address the problem of lateral control, a
two-surface fixed vertical rudder was added to the rear of the machine.
[81]
During July and August 1902, the Wright household at 7 Hawthorne
Street was full of frantic activity as Wilbur and Orville prepared once
again to travel to Kitty Hawk. On August 20, Katharine relayed to
Milton, "The flying machine is in process of making now. Will spins the
sewing machine around by the hour while Orv squats around marking the
places to sew. 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." Katharine went on further to tell her father,
"They really need to get away for a while. Will is thin and nervous and
so is Orv." Kitty Hawk would be a good remedy for the brothers, "They
think that life at Kitty Hawk cures all ills, you know." [82]
While the brothers prepared to depart for Kitty Hawk, they had some
reservations. Wilbur especially felt that he should stay in Dayton to
assist his father with the Keiter affair. Wilbur's concern stemmed from
the fact that while Milton continued his fight against Keiter, the
general opinion of the church's ruling body was against him. Feeling
that they did not want to bring the controversy into the public realm,
the rulers were content with having dismissed Keiter from his post in
the publishing house. Milton desired further action against Keiter;
specifically he wanted criminal charges filed against him. Sensing the
backlash against Milton, Keiter filed disciplinary charges against him
in May 1902. The charges accused Milton of libel, insubordination, and
breach of the guidance of the church which urged all members to settle
their differences out of court. Believing the charges were without any
legal basis, Milton ignored them. [83]
The presiding elders of Milton's circuit, the Fairmont Circuit,
appointed a special commission to investigate Keiter's charges and
Milton's conduct. In response, the commission scheduled a hearing at the
annual conference meeting on August 28. Milton, as bishop, rescheduled
the meeting until October claiming the need to complete some other
pressing business. The notice was ignored, and the hearing convened. The
hearing resulted with a verdict of guilty on all three charges, and
Milton was ordered to confess his error and apologize to the members of
the conference. If this was not carried out within sixty days, he would
face indefinite suspension. Believing in his opinion and actions, Milton
ignored the decision and proceeded with business as usual. [84]
Wilbur and Orville were not in Dayton when the hearing results were
announced. Although they considered staying in Dayton to support their
father, the brothers eventually left for Kitty Hawk. They departed on
August 25 and stayed until October 28. As in the previous year,
throughout their stay, the brothers had many guests. The first visitor
was their brother Lorin; followed by George A. Spratt, who had visited
the previous year; and Octave Chanute, who brought his assistant, August
M. Herring. [85]
During their stay, the brothers made 700 to 1,000 glides that proved
the glider was a success from the beginning. In the first two days of
the glider experiments, Wilbur and Orville made over fifty glides with
their machine. As they had in previous years, the brothers first flew
the glider as a kite. These trials showed the new wing configuration
improved the lift to drag ratio, the problems with longitudinal control
were reduced, and the new fixed vertical rudder counteracted the adverse
yaw. The next step was to fly the kite as a glider. This was the first
year that, in addition to Wilbur, Orville also piloted the glider. In
order to give themselves an opportunity to become familiar with the
controls, they secured either the wing warping or forward elevator
controls. As with the earlier flights, the glides showed the
improvements over the 1901 glider. [86]
While the 1902 glider solved some of the problems experienced with
the earlier gliders, a new problem arose. The glider responded to
crosswinds, and in some instances, these winds tipped one wing of the
glider towards the ground. In an attempt to solve this problem, the
brothers altered the wings so the tips were approximately four inches
lower than before, creating a negative dihedral. This solution caused
greater problems with lateral control than experienced in the 1901
glider. On September 23, Orville piloted the glider with both controls
free. At one point he activated the wing warping by shifting in the hip
cradle to raise a dropping wing. Preoccupied with the wings, Orville
lost track of the elevator, and the airplane crashed nose first into the
sand. Orville survived the accident, but the damage to the machine took
several days to repair. [87]
Once the glider was repaired, Wilbur and Orville resumed their
experiments. During the last flight of 1901, Wilbur experienced a new
problem when he neglected the forward rudder during a turn and the
glider dove to the ground. This reoccurred when Orville started flying
the repaired glider. The brothers termed this phenomenon "well-digging,"
and it is now known as a tailspin. Their phrase was based on how the
glider slid out of control, falling from the sky, with one wing tip
landing in the sand first. The depression made from the wing made the
Wrights think of a well. [88]
It was evident to Wilbur and Orville that the new vertical rudder, or
tail, played a role in the occurrences of well-digging. Orville shared
his remembrance of how he happened upon the solution with Fred
Kelly:
But even after it was evident that the tail had something to do
with the machine's peculiar behavior, neither brother was prepared to
explain why. Then one night Orville drank more than his customary amount
of coffee. Instead of going to sleep as usual the moment he got into
bed, he lay awake for several hours. Those extra cups of coffee may have
been important for the future of practical flight for, as he tossed
about, he figured out the explanation of the phenomenon caused by the
tail.
During those hours, Orville concluded that making the vertical tail
moveable would solve the problem. By moving the tail when a tailspin
began, the pressure that caused the glider to pivot about the low wing
could be avoided. [89]
Wilbur agreed with Orville's assessment but added a suggestion.
Hesitant to add another control to manage, Wilbur suggested controlling
the tail and the wing warping with the same system. This would still
have the positive effect of a moveable vertical rudder, but avoid
further demands on the pilot. Enthusiastic about the idea, the brothers
attached the wires controlling the tail to the wing warping system.
These alterations to the 1902 glider created a three dimensional system
of control. The forward elevator controlled the glider in the pitch
axis, the wing warping in the roll axis, and the moveable rudder in yaw.
In this final form, the 1902 glider was the first fully controllable
aircraft. The 1902 experiments were a success. [90]
While Wilbur and Orville were in Kitty Hawk, they once again left
Charlie Taylor in charge of the bicycle shop. Katharine did not get
along well with Charlie, and she often informed her brothers of the
difficulties she experienced. In a September 4 letter, she stated, "The
business is about to go up the spout to hear Charles Taylor talk."
Katharine did not believe any of Charlie's complaints were credible, but
she did have a problem. The brothers left for Kitty Hawk without leaving
any checks. She did not, "enjoy going to the store after money. Mr.
Taylor knows too much to suit me. I ought to learn something about the
store business. I despise to be at the mercy of the 'hired man'." A
month later, when Katharine once again apprised her brothers of the
situation, she and Charlie were no longer talking. "I simply can't stand
Charles Taylor so I steer clear of the store. I have been in twice to
telephone but we never said a word to each other!" [91]
With the success of the 1902 experiments, Wilbur and Orville felt
that they were in a position to attempt powered flight. In later years,
Orville described the 1902 glider experiments as demonstrating "the
efficiency of our system of maintaining equilibrium, and also the
accuracy of the laboratory work upon which the design of the glider was
based." Prior to any other research after the experiments, the ever
cautious brothers constructed another wind tunnel to confirm the
accuracy of their 1901 wind tunnel test. With the results verified, the
brothers began working on propellers and an engine for their flying
machine. [92]
Originally, the Wrights thought of using the theory of screw
propellers developed by maritime engineers and then applying their
formulas to make the propellers suitable for air. After researching ship
propellers, they discovered that these propellers were not based upon
any theory and provided none of the information the brothers sought. The
brothers spent weeks discussing alternative propeller theories and
attempting to solve the problem of creating a propeller for their
airplane. [93]
Charlie Taylor was a witness to many of these discussions, and he
recalled, "Both boys had tempers.... They would shout at one another
something terrible. I don't think they really got mad, but they sure got
awfully hot." Orville remembered that these arguments often had the
effect of each convincing the other of their point. "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 discussions began." [94]
Instead of being a hindrance, Charlie felt that these arguments were
part of the reason the Wright brothers succeeded. Through this process,
Wilbur and Orville developed approaches to a problem, and without each
other and these discussions, Charlie felt that neither of the Wright
brothers would have made strides towards solving the problem of human
flight. It was their partnership and how Wilbur and Orville worked
together, such as arguing over theories, which contributed towards their
success. [95]
One of the Wright brothers' future students, Benjamin Foulois,
noticed how well Wilbur and Orville complemented each other. He found
that Orville was the more talkative of the two, but that was not saying
much. Both brothers were quiet, but Orville was the one who would answer
when you spoke to the two of them. Wilbur would either nod in agreement
or add an incomplete sentence to Orville's response. They never answered
a question without first thinking through their reply, and sometimes
they took so long to answer that Foulois thought they were not going to
acknowledge his question. [96]
Finally, after many discussions, Wilbur and Orville began to
establish a rationale for developing an airplane propeller. The first
step in the process was the realization that a propeller functioned as
an airplane wing moving in a spiral course. The spin provided thrust to
move the plane. By March 1903, after many experiments using the wind
tunnel, the theory became clear. The brothers then designed a
transmission system for their airplane, and it evolved from their
experience in the bicycle business. They linked twin pusher propellers
to the engine with a set of bicycle chains. [97]
Immediately after returning to Dayton, Wilbur sent inquiries to
gasoline engine manufacturers about prices and delivery times for an
engine weighing no more than 180 pounds with an output of eight to nine
horsepower. No positive responses were received, and the brothers were
forced to confront the construction of an engine themselves. While the
brothers worked on the plane's structure, they asked Charlie Taylor if
he could make an engine. While he had only worked on a gasoline engine
and never built one, Charlie said he would "get busy and make one."
Wilbur, Orville, and Charlie had gained experience in 1901 constructing
the illuminating gas engine to operate the line shaft in the bicycle
shop, and with the limited knowledge the three of them possessed, the
Wrights were confident they could build an engine for the airplane. [98]
Wilbur, Orville, and Charlie did not make any drawings for the
engine. They would discuss each part and sometimes make a sketch.
Charlie would then use the sketch, usually drawn on a piece of scratch
paper, to fashion the component. By constructing the engine themselves,
Charlie was limited to the machinery for metal working already in the
bicycle shop. Therefore, he built the engine using only a lathe and
drill press operated by belts propelled by a stationary gas engine. [99]
Besides the two prerequisites Wilbur listed in his inquiries to the
engine manufacturers, an airplane engine needed one other requirement.
That was to run smoothly so no strain was placed on the transmission
chains. In order to decrease the weight of the engine, the Wrights chose
to cast the crankcase from aluminum. In the final engine, the motor
block was made of cast aluminum and the cylinders of cast iron. The
engine was water cooled with a separate radiator and a water jacket cast
into the block. The fuel would be gravity fed from a can mounted several
feet above the engine on a strut. [100]
Charlie began working on the engine in December 1902 in his spare
time from repairing bicycles. First he built a "skeleton model" to
observe how each part would function. Charlie found that "Orv and Will
were pretty thorough that way,they wouldn't take anything for granted
but worked everything out to a practical solution without too much
haste." After working through the design, Charlie started constructing a
fourcylinder engine. [101] By February
12, 1903, the engine was ready for the first test. During a test the
following day, the motor body and frame broke. Charlie had the rebuilt
engine in operation by May. [102]
Since they felt they were nearing success with powered flight, Wilbur
and Orville applied for a patent on March 23, 1903. They did not include
a power source in their patent application, for they were applying for a
patent on their flying machine, not the source of its power. What they
sought to patent and protect were the basic principles they incorporated
into the 1902 glider such as the wing warping system, complete with
rudder. [103]
LANGLEY'S GREAT AERODROME AFTER TAKE-OFF ON DECEMBER 8, 1903.
(Courtesy of National Air and Space Museum)
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The U.S. Patent Office quickly responded to the Wrights' application
indicating that they found that their application included inadequate
drawings and a vague description. For many years the patent office had
been receiving a steady flow of patent applications for various types of
flying machines. It was decided, in order to dismiss many of these
claims, that an applicant needed to prove that their machine could fly.
While the Wrights knew their machine could fly, they could not convince
the officials. Resubmitting the application, Wilbur attempted to clarify
the language. He even went so far as to send a cardboard box to describe
the wing warping technique. Once again the claim was rejected. In his
response, the reviewer suggested to the brothers that they employ a
patent attorney to assist with their application. After considering his
suggestion, Wilbur and Orville decided to wait until they successfully
flew a powered aircraft before further pursuing a patent. [104]
On September 23, 1903, Wilbur and Orville left for Kitty Hawk to test
their power-driven machine. The machine was almost complete, but it was
never fully assembled in Dayton since there was insufficient space in
the bicycle shop. Charlie Taylor remembered that when the center section
was assembled it blocked the passage between the shop and the workroom
on the first floor. In order to serve customers, they had to walk out
the side door of the workroom and around to the main door of the store.
While Wilbur and Orville were intent on completing the flyer and leaving
for Kitty Hawk, they always made time for the customers. The bicycle
shop was their main source of income to fund their experiments, and they
could not ignore the bicycle business and focus only on their
aeronautical experiments. [105]
Since they could not weigh the assembled flyer, the brothers weighed
the individual parts to estimate the overall weight of the machine at
675 pounds. While the machine weighed more than they had estimated, the
engine also produced more horsepower than needed, so Wilbur and Orville
believed there would be no difficulty. [106]
Vowing to stay at Kitty Hawk until they achieved success, the Wright
brothers encountered a few problems. On November 5, when the machine was
almost fully assembled, a propeller shaft broke. Wilbur and Orville
shipped the parts to Charlie Taylor in Dayton for repair, and the
repaired shafts arrived back in Kitty Hawk on November 20. On November
28 the propeller shaft broke once again. Requiring replacements, Orville
returned to Dayton on December 3 to assist Charlie with the
construction. Orville departed once again for Kitty Hawk on December 9
with an improved propeller shaft. [107]
While the Wrights were preparing for another trial flight in Kitty
Hawk, Samuel Langley was also ready to test his man-carrying, powered
machine. His pilot, Charles Matthews Manly, assisted in the construction
of a very light petrol powered engine to drive the machine. Manly tested
the aerodrome twice, once on October 7 and again on December 8. In both
instances the Aerodrome was launched from a houseboat moored in the
Potomac River, and each time the model plunged into the river
immediately after it was launched. As a result of these two tests, the
United States government withdrew its financial support of Langley's
research, and Langley abandoned the project with the belief that years
of research was still needed for success. [108]
ORVILLE WRIGHT TAKES OFF AT 10:35AM IN THE FIRST FREE,
CONTROLLED, AND SUSTAINED FLIGHT IN A POWER-DRIVEN, HEAVIER-THAN-AIR MACHINE.
(Courtesy of Wright State University, Special Collections and Archives)
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Without knowledge of Langley's failed tests, on December 14, Wilbur
and Orville made their first and unsuccessful attempt with the powered
machine. With Wilbur as the operator, the engine stalled 32 seconds into
the flight. Wilbur landed safely 105 feet beyond the starting position.
Even if this had been a successful flight, it would not have been the
world's first free, controlled, and sustained flight in a power-driven,
heavier-thanair machine, for the plane took off pointing down a gentle
slope to aid in generating the necessary speed for takeoff.
Tests resumed on December 17. The first trial, with Orville as pilot,
was a success. At 10:35 a.m. Orville flew a distance of 120 feet in
twelve seconds at a speed between seven and eight miles per hour. The
first free, controlled, and sustained flight in a power-driven,
heavier-thanair machine was documented with a photograph taken with the
Wrights' camera by John T. Daniel of the Kill Devil Life Saving Station.
The brothers conducted three more successful flights that day. The
longest flight was made by Wilbur who flew a distance of 852 feet in
fifty-nine seconds. Following this flight, a sudden gust of wind damaged
the machine beyond repair. [109]
Upon their success, Orville sent a telegram to their father. With
this telegram, the world was made aware of the Wright brothers' success
following four years of dedicated research. The inventive process used
by Wilbur and Orville enabled them to achieve human flight, and the
entire four years of research cost the brothers less than one thousand
dollars. From their initial concept of the need to experiment with
gliders to their focus on controlling a flying machine, the Wright
brothers brought a unique and new outlook to aeronautical research.
Their work with a wind tunnel established errors in the accepted data
tables and enabled them to achieve sufficient lift. The wing warping
system devised by the brothers along with the use of an elevator and
rudder solved the problem of three dimensional control. It was these
efforts and the brothers' synergistic working relationship that brought
them success. [110]
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