Today, a forgotten chapter in the history of
flight. The University of Houston's College of
Engineering presents this series about the machines
that make our civilization run, and the people
whose ingenuity created them.
I was hooked on airplanes in
the 1930s. I built models, and I created a vast
mental inventory. There were two kinds of flying
machines in those days: Ones that fate would permit
me to see -- like DC-3s, Piper Cubs, and blimps,
and those -- like flying wings and Japanese
Zeros -- which I
could only imagine. I knew then that I'd never see
a corporeal autogiro in flight. The
autogiro was a mythic creature -- my personal
unicorn among horses. It was then, and
still seems, destined to remain in an imagined
memory.
Instead of a wing, the autogiro had a large
propeller on top. A second, regular propeller drove
it forward. But the big overhead propeller
free-wheeled as the autogiro flew; it provided only
lift. An autogiro could take off and land in a very
short distance; but it couldn't rise vertically,
like a helicopter. If one lost power, it spun
safely back down to earth like a maple seed.
Bruce Charnov's new book, From Autogiro to
Gyroplane, tells the story of this odd
machine. It was developed by Spanish aerial pioneer
Juan de la Cierva. Cierva and his brother began
trying to build airplanes before
WW-I while he was a civil-engineering student in
Madrid. Juan de la Cierva built conventional
airplanes for several years before he began
thinking about the autogiro.
Finally one night at the opera Aida he
realized how to balance lift on advancing and
retreating blades of that overhead propeller. But
you find no propellers in Aida, so you
hear stories that he got the idea for the autogiro
from windmills in the opera Don Quixote.
In any case, two decades of autogiro development
followed. British and American companies built them
in a huge variety. Amelia Earhart tried to make the
first autogiro flight
across America in 1931. After many short hops,
she finally reached Oakland, only to learn that
someone else had set that record nine days earlier.
In the late 1930s, the more complex helicopter
appeared. It combined lift and thrust in
the overhead propeller. America created the
embryonic Vought-Sikorski
VS300, and Germany the Focke-Wulfe Fw-61.
After the war, helicopters moved to center stage,
and we heard almost nothing more about autogiros.
For twenty years, autogiros had seemed to promise
an airplane in every back yard. That didn't pan
out, but they finally did play a functional role as
WW-II scout planes. Then the helicopter appeared,
and autogiros vanished as though they had never
been.
Charnov finishes by telling about the new
technology of the Gyroplane. It's a
helicopter/autogiro composite. It, too, has both
forward and overhead propellers. But now the
overhead propeller can be driven or it can
free-wheel -- serving as a passive wing.
I said that the autogiro was my own unicorn among
horses -- an airplane which I shall always see
wearing the clothes of mythology. Well, I guess the
Gyroplane is the mortal spawn of a horse and a
unicorn. It is something I might one day actually
ride, after all.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
Charnov, B. H., From Autogiro to Gyroplane: The
Amazing Survival of an Aviation Technology.
(Foreword by John H. Lienhard.) Westport, CT: Praeger
Publishers, 2003.
The Cierva C-40 in three views
Image sources: The photo of Amelia
Earhart in an autogiro is from Charnov's book
(cited above), and it is used by courtesy of
Stephen Pitcairn, Pitcairn Aircraft Company
Archives. The Kellet Autogiro image is from a set
of airplane cards that were circulating in the late
1930s. The image of the Cierva C-40 and
the Fw-61 helicopter image are from the
Aeronautics Aircraft Spotters' Handbook,
New York: National Aeronautics Council, Inc., 1943,
and the VS300 image is courtesy of the
Vought-Sikorsky Archives.
The Engines of Our Ingenuity is
Copyright © 1988-2003 by John H.
Lienhard.
