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October 1990, Vol. 73, No.
10
Sikorsky's was the first practical helicopter, but a different
Russian and a younger Air Service got a chopper off the ground
in 1922
The Flying Octopus
By C. V. Glines
MOST aviation historians agree that Igor I. Sikorsky deserves
credit for designing, building, and flying the first practical
helicopter. His XR-4, the first rotary-winged aircraft accepted
by the Air Force, weighed 1,900 pounds and could lift 500 pounds
of payload. It first flew in January 1942 and was demonstrated
to Gen. Henry H. "Hap" Arnold the next July. General
Arnold liked what he saw. "The Army Air Force," said
he, "has taken flyers before with not so much gain promised."
One "flyer" to which General Arnold may have been
referring was an earlier helicopter venture. Sikorsky's helicopter
was not the first bought by the organization that would eventually
become the United States Air Force. World War I had stimulated
many to explore the possibility of true vertical flight. None
had solved the riddle of stability, but the potential of vertical
lift machines for military purposes continued to interest many.
Among these were a few officers of the Army Air Service who
had become intrigued with the writings of a Russian with a French
name: Dr. George de Bothezat. De Bothezat, a scientist who had
fled the Bolshevik Revolution, was a big, bearded man with a quick
wit and a violent temper. He was also an extreme egotist who once
boasted publicly, "I am the world's greatest mathematician
and scientist."
In Russia, de Bothezat had gained international renown for
his theories about vertical flight. He had earned degrees in five
countries and had published two acclaimed theses: "General
Theory of Blade Screws" and "Theory of Helicopter Stability."
Both found their way to the library of the Air Service Engineering
Division at McCook Field, near Dayton, Ohio.
In the early 1920s, McCook Field was the Air Service's engineering
and flight test center. Workers investigated, researched, and
developed any idea that might prove useful to the nation's young
air arm. Maj. Thurman H. Bane, chief of the Division, read de
Bothezat's treatises and felt that the theories had merit. He
asked his superiors for permission to contact de Bothezat and
invite him to Dayton. Permission was granted, and the Russian
emigre was delighted to accept.
After de Bothezat arrived in Dayton, Maj. Gen. Mason Patrick,
Chief of the Air Service, authorized a contract with him, without
open bidding, for the construction of a helicopter. This unusual
procedure was authorized because no other qualified bidders existed.
However, de Bothezat first had to produce a written proposal to
make the transaction legal.
Putting It on Paper
De Bothezat was exasperated by this bit of Army red tape, but
he nevertheless submitted an eighteen-page letter. "The helicopter
here disclosed," it stated, "is. . . to possess all
qualities of inherent stability and maneuverability which are
essential for the navigation of any vehicle of locomotion. The
helicopter considered is essentially composed of four lifting
blade screws identical in size and shape and disposed cross-wise."
The letter, accompanied by drawings and diagrams, further described
the principles of operation and structure of the craft. General
Patrick was impressed. In the 1921 budget, Congress appropriated
the astonishing sum of $200,000 for work on the project. De Bothezat
was hired as acting chief of the Engineering Division's Special
Research Section at an annual salary of $10,000. The government
specified that de Bothezat was to produce "drawings and data
to design, construct, and supervise flight tests of a helicopter."
In turn, the government was to provide engineering assistants,
materials, equipment, arid hangar space.
When the Engineering Division received the first set of drawings
and computations from de Bothezat, he was to receive $5,000. When
the machine was fully constructed, he would receive another $4,800.
If it actually left the ground, climbed to 300 feet, and returned
to its takeoff point without mishap, he would receive further
payments totaling $20,000. The craft was to be ready for flight
by January 1, 1922--that is, in seven months.
To keep the curious away and allow de Bothezat and his assistants
to work unmolested, the project was given "top secret"
status. Work began in a tin-roofed hangar. When the machine began
to take shape and outgrew the hangar, a wall of canvas was erected
outside to enclose it from view.
Engineers assigned to work with de Bothezat enjoyed the task,
despite the Russian's angry outbursts when things didn't go his
way. He hovered over their workbenches, watching them turn his
drawings into strangely shaped pieces of metal. He spent his waking
hours tinkering, figuring, and writing furiously.
The existence of a top secret project right under their noses
caused curious McCook test pilots to try to sneak a look at "the
thing." Some took to the air to spy on the "mad scientist."
At the end of routine test flights, they would swoop low and marvel
at the crazy collection of tubing and blades. De Bothezat would
shout curses in Russian and shake his fists, but the pilots merely
waved back. Several VIPs were allowed to view the machine, however.
These included former Secretary of War Newton D. Baker, Secretary
of Commerce Herbert Hoover, and Brig. Gen. Billy Mitchell.
Toward the end of 1921, de Bothezat realized he could not meet
the deadline and pleaded for more time. He got an extension, and
he and his assistants worked through the winter, spring, and summer,
inching toward the day of reckoning. By the fall of 1922, the
Air Service's first helicopter was near completion. On December
18, 1922, the machine was ready for the world to see.
Spectators quickly gathered around McCook Field as word of
the aircraft spread. It had snowed the day before, but it was
now sunny, with virtually no wind. Just after 9:00 a.m., the canvas
walls parted, and de Bothezat's crew pushed their pride and joy
to the center of the field.
Airborne Octopus
Several spectators gasped, snickered, and then broke into loud
guffaws. They saw a strange framework of tubes and wires built
into the shape of a giant cross, hung together with a spidery
network of pulleys, chains, and metal strands. Four giant, six-bladed
rotors were mounted on each end of the cross, and four other fans
served as stabilizers. To an onlooker, the machine was a nightmare
of steel and aluminum tubing, complicated gears, and guy wires.
It was immediately dubbed "The Flying Octopus."
Thurman Bane (by then a colonel) had decided that he would
serve as test pilot on the first flight. Taking his place in the
pilot's seat, he slowly primed the engine. and started it. The
huge contraption started to vibrate as the four giant rotors began
to turn slowly like horizontal windmills.
As Bane opened throttle, de Bothezat and his crew stood clear.
According to one McCook Field observer, "the movement seemed
graceful and there was no noise of friction in any part of the
machine. The craft began to lift itself a little--an inch, two,
three--until it was about three feet above ground. It hovered
at an altitude of two to six feet for one minute and forty-two
seconds. Hovering at this height, the helicopter drifted some
300 feet with the wind. Having drifted close to a fence, [Colonel]
Bane made a quick landing, which was done under complete control."
The powerplant in the "Octopus" was a 180-horsepower
Le Rhone engine, later replaced by a 220-horsepower British Bentley
Rotary, which rotated in a horizontal plane directly in front
of the pilot's lap. Brig. Gen. Harold R. Harris, one of the helicopter's
test pilots, once observed that "the Bentley Rotary was a
good engine except that it had a bad habit of throwing cylinders.
Fortunately, it never threw one while the tests were underway."
The controls were similar to those of the day's fixed-wing
aircraft. A stick and rudder pedals controlled the pitch of the
main blades, and an automobile-style steerwheel controlled the
pitch of the three-bladed rotors mounted above the engine. A small
hand throttle controlled the engine speed. There were so many
gears, idles, and wheels to operate, said one test pilot, that
not only looks like an octopus, it takes an octopus to fly it
"
For example, the test pilot noted, "if the engine failed,
the pilot had to reach forward to release the stop on the overall
pitch wheel [and] grasp another wheel to adjust the pitch of the
center stabilizing propellers so he could slow down the windmilling
blades. At the same time, the pilot had to maintain lateral, longitudinal,
and directional control with the stick. If he could do all this
as he was falling, a fast twist was still needed on the main pitch
control at the last minute to soften the landing."
General Harris recalled that "balancing the de Bothezat
job. . . was really a tightrope walk in four directions."
Weird, but Workable
Weird as the de Bothezat contraption looked, it made over 100
flights and accomplished all of its initial test objectives. On
January 23, 1923, it left the ground with two people aboard and
lifted a payload of 450 pounds to a height of four feet. The next
month, it set an endurance record of two minutes and forty-five
seconds. In April 1923, it lifted four men off the ground.
In the late spring of 1923, the government contracted with
de Bothezat for an improved version of the helicopter The Air
Service specified that he had to redesign the central part of
the machine to give it strength and reduce size of the main rotors
and make them less flexible. The changes, however, produced no
substantial improvements in the aircraft's performance. Reluctantly,
General Patrick ordered the project canceled.
In a long letter, Colonel Bane praised de Bothezat. "It
is my sincere belief," said the officer, "that your
helicopter is the biggest aeronautical achievement since the first
flight of the Wright brothers." No less a personage than
Thomas A. Edison, who had experimented with helicopters in the
1880s, told the Russian, "You certainly have made a great
advance; in fact, as far as I know, the first successful helicopter.
"
De Bothezat was keenly disappointed by the cancellation but
went on to other projects. In 1936, he built another experimental
model, which did not show marked improvement over the earlier
version. Even so, he appeared before the House Military Affairs
Committee that year to advocate continued helicopter research.
He predicted that the chopper "would give rise to an entirely
new method of warfare, battalions of swift and silently flying
machine guns, able to land at night behind [an] enemy's lines."
On February 1, 1940, de Bothezat died in Boston following an
emergency operation. He was fifty-eight. Long before then, de
Bothezat's "Flying Octopus" had been sent to the McCook
salvage yard. However, one rotor hub and four main blades have
been preserved and are in the National Air and Space Museum's
collection in Washington, D. C.
C. V. Glines is a regular contributor to this
magazine. A retired Air Force colonel, he is a free-lance writer
and the author of many books, most recently Attack on Yamamoto.
His last article for AIR FORCE Magazine, "Their Finest
Hour" appeared in the September 1990 issue.
Copyright Air
Force Association. All rights reserved
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