in the spotlight
A Brief History of
Dirigible Flight
George Denniston, EAA 1004872
One of the earliest pioneers of dirigible
flight was Alberto Santos-Dumont
of Brazil. Son of a coffee grower, he
sailed to Paris and single-mindedly
pursued his goal of conquering the air.
In 1900 the Deutsch Prize of
100,000 francs was offered to the
first aeronaut who could fly the 7 miles
from the St. Cloud section of Paris,
around the Eiffel Tower, and back,
in 30 minutes. In July 1901, Santos-Dumont made his first attempt in his
Airship No. 5. On the return leg, the
engine stalled, and he crashed. In
his second attempt, a month later, a
defective valve permitted hydrogen to
escape, and he crashed again. Working
night and day, he quickly built another
ship with a more powerful engine.
Meanwhile the race committee,
hoping for a French rival, changed the
rules. Now, one had to land at the
finish—not just cross it—within the
30-minute time limit. Santos-Dumont’s
Airship No. 6 rounded the Eiffel Tower
after only nine minutes. But 500 yards
out from the Tower on the return trip,
the motor misfired. The diminutive
Santos-Dumont ( 5 feet, 2 inches, 110
pounds) walked back from the gondola
to the engine and got it running again
as all of Paris watched. He crossed the
finish line at 2 9 minutes, 30 seconds,
but took another minute to land.
“Have I won?” he shouted.
The crowd yelled, “OUI!” but the
timekeeper said he missed by 40
seconds. Two weeks later, he was
declared the winner. He gave 75,000
francs to the poor of Paris and divided
the remaining 25,000 francs among
his workmen.
In Germany, Count Ferdinand von
Zeppelin flew for the first time in
1900 over Lake Constance, between
Germany and Switzerland. Zeppelins
offered regular passenger service
around Germany before World War I.
During the war they were used to spot
approaching warships and made 51
bombing raids on England.
The count died at the end of the
war, and Hugo Eckener took over the
dream. He overcame huge obstacles
to build the Graf Zeppelin and later
the Hindenburg. Beginning in 1928
and lasting to 1937, the Graf circled
the world and then regularly scheduled
flights between Germany and Brazil
and Germany and the United States.
This was the golden age of lighter-than-air craft. The Empire State
Building, built in 1934, originally
had its peak designed as a mast for
mooring a zeppelin. Eckener was
interested in the peaceful use of these
ships and refused to support the Nazi
cause. He quickly named his ship the
Hindenburg, so it would not be named
for Adolf Hitler.
The demise of the Hindenburg, in
a fire of unknown origin at Lakehurst,
New Jersey, in 1937, put an end to the
age. World War II intervened, and it was
not until 1989 that an effort was made
to reintroduce a new Zeppelin. A trust
fund from the earlier Zeppelin Company
was used to design and produce a
Zeppelin with new technology—the
semi-rigid Zeppelin NT.
The new Zeppelin is much smaller
than the Graf; 8,225 cubic meters
versus 200,000 cubic meters in
volume. The Graf used hydrogen, while
the new ships use helium. Though far
more dangerous, hydrogen has twice
the lifting power of inert helium.
The hull of the new Zeppelin
is made of a three-layer laminate:
Tedlar, a polyester for stability, and a
polyurethane. Early airbags were made
of cotton and lined with goldbeater’s
skin, to contain the hydrogen.
Goldbeater’s skin, used originally to
beat gold into thin sheets, is a specially
treated inner lining of the stomach of a
cow; some 200,000 were required for
a large airship. It was.
The early Zeppelins had means of
collecting rainwater and condensation,
to compensate for fuel burned.
Without this, they might become
too light and become unable to land
without having to valve off hydrogen.
The Zeppelin NT takes off up to 673
pounds heavier than neutral and uses
its engines to take it up. If it becomes
too light, it uses its engines to power
it back to earth.
