Hydrogen snafu.

Gasoline is highly flamable/explosive too...

 

From autopsy evidence most of those who died of burns in the Hindenburg incident died from diesel fuel burns. The hydrogen went straight up and out when released. Hydrogen generally turns into a blow torch in an incident like you describe. Bad but controllable. Big problem with hydrogen is how you make it though it is only a energy storage chemical not a fuel.

 

During the early days of the US Space Program, and the use of hydrogen as a fuel, some interesting and surprising characteristics of hydrogen were discovered.

First, when a small to moderate amount of pure gaseous hydrogen escaped into still air (no wind), it tended to form into a sphere and hang about 3-6 feet off the ground. It would remain this way until a slight breeze sprang up which began to disperse the sphere. Hydrogen is lighter than air, but varying temperature layers in still air would cause funny things to happen, especially in the warm Florida environment.

Second, if the hydrogen sphere ignited, it would burn only on the perimeter where it was in contact with the air. The hydrogen on the inside of the sphere, being pure and having no oxygen to support combustion, would burn only as the outer layer burned away.

Third, pure hydrogen burns with a flame that is invisible. Initially, many persons at Cape Canaveral were severly burned because they walked into a burning sphere. Very quickly, if a hydrogen leak was suspected, people began to walk carrying straw brooms straight out in front. If the broom straw caught fire......! Eventually, sensors were developed to detect hydrogen leaks, and especially heated areas due to burning hydrogen. (straw brooms were supplied beside every exterior door of buildings near hydrogen facilities throughout the complex.)

Generally, hydrogen becomes explosive only when it has been mixed with air or other elements that support combustion before it is ignited. The famous Hindenburg film shows visible flames because of the other combustibles in the mix.

This is from 40-45 year-old memories, so please forgive minor mistakes.

 

Most of the visible burning was the frame and other components including the engine fuel. Most of the hydrogen went up and out, at least according to one analysis I read.

 

Lots of people also died because they panicked and jumped. Those that did not jump and were not caught in the diesel fire rode the gondola gently to earth and survived. Perhaps the greatest disaster was the famous radio broadcast of the hysterical announcer, whose sensationalist reporting put an end to a mode of transportation that was probably safer than either cars or airplanes.

There has never been a death in a helium-filled blimp or dirigible.

While I feel that hydrogen as it's presently being promoted is a boondoggle, it is safer than gasoline, and as others have remarked above, it seldom explodes.

 

When my mother was a little girl, she saw the Graff Zeppelin. She was so excited she ran home to tell her mother, leaving my aunt behind. My grandmother asked my mother, "Where's your sister?" My mom was terrified. "I've lost my sister!!!" She ran back to school in tears, to find my aunt calmly waiting where she had left her.

 

If I ever get the money, I swear, I'm going to indulge myself and build a 1,000 foot Zepplin :mrgreen:.

After I read the Hindenburg was only 87 feet shorter than the Titanic...I realized that things of such enormity need to patrol the skies again. :mrgreen:

 

I'll fly myself to where the furnace isn't required. :wink:

 

Although I agree that have been very few, if any deaths due to the helium used in helium-filled airships, there have been at least 89 deaths caused while flying those ships.

The U.S. Navy built four helium-filled rigid airships based on Zeppelin designs, which were commissioned to active duty:

>USS Shenandoah, 1923-1925, broke up in a storm over Ohio, 14 died.
>USS Los Angeles, 1924-1932, decommissioned 6/1932, no loss of life.
>USS Akron, 1931-1933, lost in a storm off New Jersey coast, 73 died.
>USS Macon, 1933-1935, lost in a storm off California coast, 2 died.

The Navy also built many non-rigid airships (Blimps), many of which are still in service and flying. For those interested, here is one of many websites.

http://www.bluejacket.com/usn_avi_lta.html

I think traveling in a rigid airship would be a great experience. However, as the Navy found out, they are delicate craft, not as strong structurally as a commercial airliner. So I'm afraid they would be profitable only as tourist attractions or weather sensitive "cruise liners".

BTW, when Uncle Sam, in his infinite wisdom showed me the way from snow-bound New Hampshire to the sunny Mississippi Gulf Coast in the mid-50's, I realized there could be life without SNOW....and I like it!

 

most of the people in the hindenburg died as a result of falls from heights. the 2nd cause of death was heart attacks... about 6 i think... only the crew burned.

the hindenburg was well publicized but not that many people died. only about 29?? people died. and it has been a goal of the scientific community to show that hydrogen does not explode easily. in fact its rather difficult. however, it can explode and does but the mechanism is the same as a grain elevator explosion. the concentration has to be just right. a hydrogen explosion would be a fluke more than the rule.

 

well dramatic images are often etched in our minds and the hindenburg explosion was very dramatic. however it is unfortunate that hydrogen got such a bad rap since it is estimated that less than 5% of the hydrogen in the hindenburg burned at all.

in a demo for hydrogen vehicles, there was a video going around the internet of scientists trying to blow up a hydrogen tank. besides shooting it with a rifle, throwing it in a fire, amongst other very destructive things, they failed to blow the tank up. it did burn but at a very leisurely rate.

but gasoline burns in a similiar fashion. anyone who has had a malfunctioning carburator will attest to the fact that getting gasoline to explode isnt all that easy either. for a gas engine to work, the gas must be burned in a mixture that explodes... just plain burning it wont make your car go anywhere.

The Prius is still trying to overcome the "plug it in" stigma...

 

Hydrogen is relatively safe, but there are plenty of other reasons why it makes a lousy vehicle fuel.

 

About 20 years ago, a magazine pointed out that a tankerload of Liquid Natural Gas would go off like a small H-Bomb if a fire broke out.

http://tinyurl.com/54a5g shows somebody still keeps an eye on them...