Regular
readers of this blog may have
noticed a recurring interest in innovations in transportation and communications—the
things that have tended to tie together
our shrinking world. But sometimes I am stunned to discover an innovation years—decades—before I
ever suspected. Take the notion of powered flight—the ability to propel
and control some kind of aircraft over a distance by a mechanical
engine. I assumed that it would require some sort of internal combustion engine.
I never even considered the possibility of steam—the engines themselves were heavy and required quantities of water and fuel, not to
mention the inherit dangers of fire, heat, and flying cinders.
So
imagine my astonishment to discover that just such a flight occurred on September 24, 1854 and that powered flight was just one of several innovations.
That
year Henri Giffard was a 27 year old
French engineer. Two years earlier he had his first experience
with lighter than air craft when he collaborated with another engineer named
Jullien to build an airship with a propeller driven by clockwork. That craft had an elongated hydrogen
filled balloon with ends that tapered to points. But the clockwork
propeller could not generate enough
energy to move the balloon very far in perfectly still conditions—or for very long until the engine wound down. It was
also lacked any means of steering or
controlling the movement of the flight. But
the effort had showed that a propeller could indeed, propel if a reliable source of power could be found
to turn it.
In
1851 Giffard patented the “application
of steam in the airship travel” and a year later built a remarkable small engine weighing just 250 pounds
with a boiler and fuel—coke—that added another 150 Lbs. That was light enough that a gas envelope could be built capable of lifting it plus the weight of a single passenger/operator. Giffard
built the first ever true dirigible—a
term derived from a French word meaning steerable.
That meant an airship with a semi-rigid gas envelope as opposed to
an inflatable bag, that could move
under its own power, and that could be maneuvered.
The
engine was just one of Giffard’s innovations.
It produced 2,200 watts or three horsepower to
turn a three-bladed, rear mounted
pusher propeller. To put it in
perspective, that is about the same power as generated by a modern steam iron, but it was
enough. The engine was mounted on a platform along
with the operator which was suspended
from a long beam slung below the 144
foot long envelope. At the rear
of the beam was a moveable triangular
sail that acted as vertical rudder
enabling the aircraft to maneuver.
The trickiest problem was what to do with
the cinders that would inevitably escape the combustion
chamber and rise imperiling the
highly flammable hydrogen in the
envelope. Giffard devised a long exhaust tube that pointed
down and behind the engine
instead of a top mounted smokestack
common in steam engines. That directed
sparks down and away from the envelope and hopefully the forward movement of
the air ship would be fast enough to keep them from rising to the rigid
bag. All in all it was a remarkable
construction.
Giffard
took off from the Paris Hippodrome
and flew 17 miles to Elancourt, near
Trappes in three hours for an average speed of six miles per hour. Along
the way he made several turns and
even flew in short circles to prove
that his ship was controllable. The
original plan was to take on more fuel and water and return to Paris. But Giffard found that his engine was not
powerful enough to move the ship against even a light headwind.
The
Giffard Dirigible never flew again. Attempts to improve on it were stymied by the additional weight of
steam engines powerful enough for practical
use. The future of the Dirigible
had to wait until the development of light and practical engines. In 1872 Paul
Haenlein flew a hot air craft—a blimp—with an internal combustion
engine running on the coal gas used
to inflate the envelope. The La
France was launched for the French
Army by Charles Renard and Arthur Contantin Krebs in 1884
propelled by a battery powered electric
motor. In its maiden five mile flight it became the first airship ever to
complete a round trip.
A hydrogen-lift dirigible powered by the
first use of such an internal combustion engine had to wait until 1888 when Dr. Frederich Wölfert built an airship
powered by Daimler Motoren Gessellschaft
gasoline engines, 36 years after Giffard.
As
for the inventor, he had more innovation in him. In 1858 he invented the injector, a type of pump
that uses “the Venturi effect of a
converging/diverging nozzle to convert the pressure energy of a motive fluid to
velocity energy which creates a low pressure zone that draws in and entrains a
suction fluid.” Don’t ask me what that
means—it’s all engineering Greek to me, but trust me it was an important technological breakthrough and made
Giffard a very wealthy man.
In
fact, he became something of a national
hero for that and was made a Chevalier of the Légion d’ honneur
in 1866. And he was not done with
playing around with lighter-than-air-craft.
In 1876 he made a famous tethered
flight over Paris in a hydrogen balloon which was captured in a famous early photograph.
Despondent over declining health, Giffard committed suicide on April 14, 1882. He left his fortune to the people of France to be used for humanitarian and scientific causes. He was so esteemed by his countrymen that he is among the 72 great notables whose names are inscribed on the Eiffel Tower.
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