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This
print shows the Hindenburg in flames above Lakehurst
Naval Air Station on May 6th, 1937. (The
National Archives)
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The
Mystery of the Hindenburg Disaster
It was
the largest airship ever built; over eight-hundred feet long
from its nose to its massive tail fins. It was the height of
luxury travel and in the course of two seasons carried over
2,656 people across the Atlantic between Germany to New York
and Rio de Janeiro. It was called the Hindenburg and the space
of 37 seconds this mighty zeppelin was destroyed in a fire that
killed a third of its crew and passengers and left spectators
crying in horror.
What
caused this catastrophe? Was it negligence, sabotage, or as
Hitler called it, "An act of God"?
The
Dirigible
The
first successful dirigible (a balloon that has engines to control
its horizontal movement) was built in France in 1852. Although
other countries built these types of airships, the Germans quickly
became the most advanced builders of this form of lighter-than-air
technology. Count Ferdinand von Zeppelin, a German businessman,
built a fleet of experimental dirigibles. The type of airships
Zeppelin built were spindle-shaped with a rigid internal steel
structure (unlike the flexible bodied blimps common today).
Inside the craft were large bags filled with gas that gave the
ship its lift, as well as catwalks to allow the crew to move
back and forth inside the hull to service the airship. Beneath
the craft was a gondola which carried the crew and passengers.
By 1911 Zeppelin's airship LZ-10 (also known as the Schwaben)
was in passenger service and would go onto make 218 flights
carrying 1,553 passengers. Zeppelin became so well-known for
this type of dirigible that his name soon became synonymous
with that type of airship.
Starting
in 1914, the beginning of WWI, the Count's zeppelins were used
to drop bombs on cities in a number of European countries. They
made over fifty raids on London alone, dropping nearly 200 tons
of explosives. As the war progressed, however, most of the German's
zeppelin fleet was destroyed by British guns or aircraft. The
gas that gave them their lift, hydrogen, was very flammable,
and even a small bomb hitting a zeppelin could reduce it to
ashes in just a few minutes.
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The
LZ7, one of Count Zeppelin's early ships (also known as
the Deutschland), can be considered the first true
passenger aircraft. It first flew on October 19th, 1910.
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After
the war Germany again began building large airships. As part
of war reparations the Germans built the ZR-3 Los Angeles for
the U.S. Navy. In 1928 the Zeppelin Company built what was the
most successful passenger dirigible of all time, the Graf Zeppelin.
The
Graf Zeppelin was a hundred feet longer than any other airship
ever built and stretched 776 feet from nose to tail fins. It
was designed as a passenger liner to compete with the ocean
liners crossing the Atlantic. With a maximum speed of 80 miles
per hour, it cut the time it took to make the trip by more than
two-thirds. The passenger cabin was outfitted with drapes and
thick carpeting. Dinner was made by professional chefs and was
served using silverware, crystal and fine china. Time magazine
declared, "Certainly for trans-oceanic trips, the airship is
the thing."
Constructing
The Hindenburg
The
Graf Zeppelin was so successful that the Zeppelin Company planned
a new airship. One that would be bigger, faster and carry more
passengers with more luxurious amenities. It would be named
after a national hero who had been elected Germany's president
in 1925. It would be called the Hindenburg.
The
Hindenburg was not only longer than the Graf Zeppelin, it was
an extra 35 feet wide. This meant it had nearly twice the volume
for lifting gas (7,062,000 cubic feet) than the Graf Zeppelin.
There was a reason for this. The Hindenburg's designers had
decided to fill the new dirigible with helium gas, not hydrogen.
Helium, unlike hydrogen, does not burn, making it safer. However,
it doesn't produce as much lift as hydrogen, so the extra volume
the Hindenburg had for gas was an important feature.
The
Hindenburg never got its helium, though. At that time helium
was difficult to produce and the United States had a monopoly
on the manufacture of it. When the Americans saw that Hitler
was in power in Germany, they feared he would use the gas for
military purposes and therefore would not sell the Germans the
helium necessary to fill the Hindenburg. The Zeppelin Company
was forced to redesign the ship for hydrogen and make changes
to minimize the possibility of fire.
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The
frame of the Hindenburg under construction. (Credit:
Bundesarchiv, Bild 146-1986-127-05 / CC-BY-SA)
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Though
it might seem strange to us today, back then the airship seemed
to be the wave of the future in travel. At that time crossing
the Atlantic in an airplane was risky business. Planes could
travel only short distances carrying a minimum of weight and
required constant refueling. To many the zeppelins was the natural
successor to the ocean liner. The Zeppelin Company planned that
the Hindenburg would be the first of a fleet of airships plying
the skies of the world.
Even
today the Hindenburg remains the largest aircraft ever flown.
Some of the smaller, modern advertising blimps have a total
length only slightly larger than the girth of the Hindenburg.
If the Hindenburg stood on end it would dwarf the Washington
Monument. It could lift 112 tons beyond its own weight, an incredible
amount for that time. Passengers enjoyed staterooms with private
showers. The dining room served the finest food on blue and
gold porcelain place settings. The ship provided the passengers
a spectacular view along its windowed 200-foot-long promenade
deck. One restriction the ship had though was smoking. Because
of the hydrogen, smoking was permitted only in a special fireproof
room.
Final
Flight
A one-way
trip across the Atlantic cost $400 and took only two days. Flights
began in 1936 with the airship making a total of six trips to
Rio de Janeiro and ten trips to New York City carrying a total
of 2,656 passengers. In 1937 it made a trip to Rio then returned
to Germany. On May 3rd, 1937, the Zeppelin departed Frankfurt
for North America carrying 97 people. It would be the first
trip to New York City that season.
The
trip went smoothly and by 11:40 A.M. on May 6th the airship
was passing over Boston. Landing at the Naval Air Station in
Lakehurst was delayed due to bad weather, so the ship's captain,
Commander Max Pruss, decided to linger over New York City, giving
his passengers spectacular views of the Empire State Building,
the Bronx, Harlem, Central Park, the Battery, Times Square,
the Statue of Liberty and Ebbets Field (where a game was being
played between the Dodgers and the Pittsburgh Pirates).
At 4
P.M. the Hindenburg arrived over Lakehurst, but the weather
was still worrisome. Commander Pruss decided to take the ship
southeast until he hit shore, then north to Asbury Park, then
finally inland back to Lakehurst. At 6:12 Charles E. Rosendahl,
Commanding Officer of the Lakehurst N.A.S., sent a message to
the Hindenburg: "Conditions now considered suitable for landing."
Eleven minutes later a stronger message followed: "Recommend
landing now."
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The
lounge of the Hindenburg allowed the passengers to watch
the view below.
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The
Landing
It was
almost a half hour later, at 7:00 P.M., that the Hindenburg
started its landing. It circled the base, dropping its altitude
from 600 to 300 feet and aligned itself so it was headed into
the wind. As it approached the mooring mast, Captain Pruss realized
he was going a little too fast. Also the wind was changing direction.
Given that he was already late, he decided not to do a complete
go around, but slow the ship and change his approach by making
a sharp "S" turn, first left, then right.
To further
complicate things for the captain, the airship was losing trim.
The tail section was dropping. This was not particularly odd
as it had been raining the water tended to cling more to the
rear of the ship than the front, making it heavier. Puss ordered
some ballast dropped and six crewmen were sent scurrying to
the bow of the dirigible to balance it. The turn worked and
the zeppelin's nose finally faced the mooring mast where it
would be secured. As the Hindenburg got within 700 feet of the
mast, the engines were reversed, bringing the ship to a stop.
Ropes were dropped to allow the ground crew to tow the ship
into position. At this point the Zeppelin was hanging about
275 off the ground. It was 7:25 P.M..
On the
ground a radio reporter named Herbert Morrison was covering
the airship's arrival and his comments were recorded for prosperity:
...It's
practically standing still now. They've dropped ropes out of
the nose of the ship, and it's been taken a hold of down on
the field by a number of men. It's starting to rain again; the
rain had slacked up a little bit. The back motors of the ship
are just holding it, just enough to keep it from --"
"It
burst into flames! ... It's fire and it's crashing! It's crashing
terrible! Oh, my! Get out of the way, please! It's burning,
bursting into flames and is falling on the mooring mast, and
all the folks agree that this is terrible. This is the worst
of the worst catastrophes in the world! ...There's smoke, and
there's flames, now, and the frame is crashing to the ground,
not quite to the mooring mast...Oh, the humanity, and all the
passengers screaming around here!
The
flames were first visible towards the tail of the ship, then
within seconds the hydrogen in the gas bags caught on and the
whole aft of the craft was engulfed in a mass of flame and smoke
that towered hundreds of feet into the sky. As the hydrogen
in the rear of the ship burned, the rear of the Hindenburg lost
its lift and fell to the ground and its nose pointed upwards
at a forty-five degree angle. Then as the flames raced through
to the bow, it also fell. In just 37 seconds since the first
flames were spotted the ship lay on the ground, the skeleton
of its framework the only thing visible through the fire. Passengers
jumped from windows and ran for safety. One cabin boy had his
life saved when a water tank burst above his head. Of the 97
people on board, miraculously 62 managed to escape with their
lives, including the ship's captain.
An investigation
into the cause of the disaster was made both by the United States
and the German governments. They concluded a hydrogen leak was
ignited by a spark of static electricity. Both governments wanted
to close the book on the disaster. The Americans were anxious
to avoid an international incident and the Germans were embarrassed
that the cause might have been a design flaw in the ship or
the result of foul play.
The
Gas Leak Theory
Some
theories suggest that Commander Pruss's final turns to land
were too sharp and they caused a support wire to snap inside
the ship tearing open one of the hydrogen gas cells. The leaking
gas then might have been set off by a rare, natural electrical
phenomenon known was St. Elmo's fire. St. Elmo's fire is usually
seen as a static electric charge around high objects (like church
steeples) during stormy weather. Given the weather on that day,
it is very likely that the ship was carrying a static electric
charge. Just before the fire broke out, witnesses saw a fluttering
movement of the ship's skin near the rear of the vessel. Some
people argue this was caused by escaping gas. Other witnesses
noticed a blue glow around the rear of the vessel that might
have been St. Elmo's fire. If the gas escaped out a ventilation
shaft and met the static electric discharge, it might well have
triggered the fire.
The
Lightning Theory
Instead
of st. Elmo's Fire, lightning is sometimes blamed as the cause
of the fire. However, the Hindenburg had been struck several
times before by lightning with no damage. If lightning was the
cause of the disaster, it seems it must have been coupled with
a gas leak, as with the above theory. However, no witnesses
saw lightning strike the ship and there were no known thunderstorms
in the immediate area.
Diesel
Theory
This
theory suggests that the diesel fuel used to power the engines
may have started the fire. A leak from a malfunctioning fuel
pump might have ignited if the fuel reached a hot surface like
the engine block. The pods where the engines were housed, however,
were not by all accounts the location where the fire started.
Initially
engineers suspected that sparks from a backfiring engine might
have ignited hydrogen from a leak, but tests showed that these
type of sparks were not actually hot enough to have set the
gas on fire.
The
Flammable Skin Theory
A theory
suggested by Addison Bain, former manager of NASA's hydrogen
program, was that the initial fire was not caused by burning
hydrogen. Hydrogen burns without much of a visible flame, but
witnesses described the fire as extremely colorful. Bain thinks
the doping solution used to stretch and waterproof the hull
was responsible. The compound, a layer of iron oxide covered
with coats of cellulose butyrate acetate mixed with powdered
aluminum, is very similar to a mixture used to power solid fuel
rockets. "The Hindenburg was literally painted with rocket fuel,"
says Bain.
Bain
suspects that the Germans figured out the real cause, though
they didn't want to admit they'd made such a dangerous mistake.
The doping solution used on the Graf Zeppelin II, completed
after the Hindenburg disaster, was changed to include a fireproofing
agent and the aluminum was replaced with bronze which is less
combustible.
Bain
thinks the fire was started by a build-up of static charge from
the storm on the craft's surface and frame. When the mooring
ropes (wet from the storm) were dropped to the ground, the frame
discharged, creating an electrical differential between the
frame and covering which started the fire.
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The
remains of the Hindenburg on the ground just minutes after
the first flames appeared.
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Tests
have been run with remains of the covering, however, that show
that although it is flammable , it doesn't burn with the speed
needed to explain the rapid expansion of the fire through the
whole ship. If the fire did start with the skin, it seems it
must have ignited the hydrogen cells almost immediately.
The
Sabotage Theory
Some
of the crew that survived, including Commander Pruss, suspected
the fire was sabotage. The Hindenburg was more than just a German
airship. It was a symbol of German power and technical prowess.
Hitler's government, which had helped pay for the Hindenburg's
construction, had employed it for such jobs as making propaganda
appearances over the 1936 Olympic Games in Berlin. Each of the
huge tail fins of the Hindenburg wore the swastika emblem, the
symbol of Hitler's Nazi party. Officials had been concerned
even before the ship reached New York that someone opposing
Hitler might make a terrorist attack upon the craft.
If a
saboteur was at work, it must have been one of the crew or passengers.
If so, that person may have placed a time bomb along one of
the ship's internal catwalks. Most likely it detonated prematurely,
or the saboteur did not count on the craft being so late at
arriving and could not return to the bomb to reset the timing
mechanism. Either way the saboteur may have died in the resulting
explosion. A bomb placed near the rear of the craft might have
explained the initial flare forward of the tail fin as reported
by witnesses as flames from the explosion shot up the gas ventilation
shaft to burst out the top of its hood. The initial explosion
would have ruptured the hydrogen gas cells, causing a more powerful
second explosion that destroyed the craft.
Suspicion
for the sabotage initially fell upon Joseph Spah, a passenger
who survived. On several occasions Spah, a New Jersey resident,
had gone unescorted into the cargo area of the ship to visit
his dog that he was bringing home to his children. This might
have given him the opportunity to place a bomb. Later, others
suspected that Erich Spehl, an introverted crewman who perished
in the fire, might have been the saboteur. Spehl was thought
to have had anti-Nazi leanings.
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The
Hindenburg was nearly the size of the Titanic.
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There
is no proof against either of these gentlemen and in a search
of the wreckage no parts of a bomb were found. Any time bomb
would require a timer mechanism which probably would have survived
the explosion.
End
of An Era
Today,
the official results of the investigation that static electricity
set off leaking hydrogen still stand, despite the various theories.
One thing is for sure, though, the destruction of the Hindenburg
signaled the end of the great zeppelin passenger liners. No
zeppelin ever carried another passenger after the Hindenburg
disaster. The Graf Zeppelin II which was to be the Hindenburg's
sister ship, never entered passenger service. At the start of
W.W.II, it was brought into military service for a short time,
then dismantled and the parts used for the war effort.
By the
end of the war the jet engine had been invented and transatlantic
passenger service soon was carried out with a reliability and
speed that could not be matched by lighter-than-aircraft. Memories
of the horror of the Hindenburg disaster lingered on, killing
any future for the large, rigid, passenger airships. The zeppelin,
once thought to be the wave of the future, was suddenly a thing
of the past.
What's
is like to be part of a TV documentary on the Hindenburg. Read
the curator's blog on his day with the Travel Channel here!
Copyright
2001-2013Lee Krystek. All Rights Reserved.