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They still can't outrun thunderstorms.

Indeed. You would either not fly in thunderstorms, or you would choose a route that doesn't fly through them.

But at least now we know where the thunderstorms are, and have moderately good predictions as to where they're going. In the 1930s they didn't.

They're inherently slow, wallowing creatures. They're only "efficient" because they're so incredibly slow compared to bicycles

Well, Hindenburg's top speed was 84 miles per hour, with a cruising speed of 76 mph. You'd be hard pressed to hit that on a bicycle.

http://www.airships.net/hinden...

...

Actually launching and retrieving flying vehiclies from massive airships is nothing new. the US Akron and US Macon were blimp aircraft carriers carring multiple planes able to both launch and retrieve.

http://www.airships.net/us-nav...
https://en.wikipedia.org/wiki/...
http://www.history.com/topics/...

the russians even built planes that other planes could launch from
https://en.wikipedia.org/wiki/...

and Darpa still wants these:
http://www.popsci.com/article/...

and both the russians and Lockeed developed concept aircraft based on nuclear powered super planes with runways built into them:
https://forums.spacebattles.co...
russina surface effects nuclear powered sea skimmer concept:
http://englishrussia.com/2015/...

A quick check gives a list of disasters, the last ones before Hindenburg I copy-pasted. They feel pretty horrible. Dumb shit happens.

http://www.airships.net/hydrog...

Roma (February 21, 1922)

The United States Army airship Roma (built by Umberto Nobile) ignited when it hit high-tension electrical wires near Langley Field at Hampton Roads, Virginia, killing 34 of the ship’s 45 crew members. After the Roma disaster the United States government decided never again to inflate an airship with hydrogen.

Dixmude (December 21, 1923)

The French-operated Dixmude was destroyed over the Mediterranean Sea near the coast of Sicily by a hydrogen explosion visible from miles away. Dixmude’s gas cells had apparently been contaminated with air, creating an explosive mixture, and the ship may have been lifted by updrafts in a thunderstorm, causing hydrogen to be vented and then ignited by the electrically charged atmosphere.

R101 (October 5, 1930)

The poorly-designed British R101 lost altitude and sank into a hillside near Beauvais, France. The impact was slight and caused few if any injuries, but the ship’s hydrogen ignited and the ensuing inferno killed 48 of the 55 passengers and crew.

Actually, we could do so safely. Sure, hydrogen burns, but only in the presence of oxygen. An envelope filled with N2 around each hydrogen cell would make a Hindenburg-style explosion pretty much impossible.

Also, because the H2 molecule, being composed of two atoms, is twice as large as the He atom (helium doesn't pair with itself to form molecules), which only has one atom, it will take MUCH longer for the hydrogen to escape through the pores of the gas bag/lifting cell. Now because a hydrogen atom is 4x lighter than a helium atom, a volume of hydrogen molecules is still halt the weight of the same volume of helium atoms.

The atomic weight of a helium atom (4.002) is approximately four times that of an individual hydrogen atom (1.007), but since gaseous hydrogen is a diatomic molecule containing two hydrogen atoms (H2), helium gas is only twice as heavy as hydrogen gas.

Hydrogen is cheaper, gives more lift, and you can even make it on site from electrolysis of H2O, same as some large volume muffler shops do to get the oxygen for their oxy-acetylene torches because it works out cheaper than bottled compressed O2.

LZ-126/U.S.S. Los Angeles gives a real world example of the difference between operating the same ship with helium versus hydrogen. When the German-built LZ-126 flew from Germany to the United States for delivery to the U.S. Navy in 1924 it was inflated with hydrogen, and the ship made the flight from Friedrichshafen, Germany to Lakehurst, New Jersey — 5,006 miles — nonstop. When the United States Navy operated the same ship with helium, as U.S.S. Los Angeles, its range was limited to 3,925 statute miles and it could not have made the same transatlantic flight. And never again did the ship fly as long as it did on its delivery flight with hydrogen, which lasted 81 hours, 32 minutes; ZR-3’s longest flight with helium was a little over 48 hours.

Not only does helium suck as a lifting gas, if the Hindenburg had used helium instead of hydrogen,. it would have never got ff the ground.

http://www.airships.net/hydrog...

It is very hard for me to get exact numbers in few minutes, but we would need to compare amount of people transported by dirigibles/number of deaths to amount of people transported by planes/number of deaths. I have no doubts that more people died in airplane crashes over all time, but at same time I feel that number of people who survived plane flights will anyway make this ratio better by orders of magnitude.

Big part of it might be due to maturity of technology - if we had dirigibles now, they would be quite flawless. But I don't think that you can compare 1900-1940 era of dirigibles to 1950+ era of commercial aviaton in any kind of safety metrics and have dirigibles come on top.

Classically, containing hydrogen gas is a worse leakage problem than helium, but this is primarily due to the other properties like flammability and metal embrittlement.

Strictly considering leakage rates, Graham's law of effusion says that the rate of effusion is inversely proportional to the square rate of the molecular weights. So H2 leaks faster than He by a factor of about 1.414. Graham's law is of course an approximation as it ignores that molecular size is not strictly proportional to molecular weight, but it should be quite accurate when molecular sizes of the gas are considerably less than the holes in the container.

Given that He is very much smaller then H2, I would expect somewhat less difference in effusion rates than than predicted by Graham's law, though this may not be measurable as far as I know.

But for unmanned operation, I don't know why Google would not use H2. H2 is much cheaper and can be easily made on site with little technology.

Theoretically, pure He has 93% the lifting capacity of H2 -- but your lifting gas is never pure and structural elements such as the balloon and frame have the same amount of dead weight in either case. So, in terms of payload, H2 is significantly better then He.

A very nice article on lift comparison. points out that the Hindenburg design would simply not work using He as the lifting gas due to the "small difference" in buoyancy of the 2 gases.

Very real. The USS Macon and USS Acron were built as flying aircraft carriers, carrying 5 fighters. Not just carry them under the airship's belly, Last Crusade style, but inside the airship. Fascinating aircraft, something out of a steampunky SF story.

Flying aircraft carriers? It's been done

Counter-examples (plural):

http://www.airships.net/hydrogen-airship-accidents

The Hindenburg was just the last and most famous of dozens of fiery hydrogen airship disasters. It was famous because it was one of the first disasters to be reported live over radio broadcast, not to mention the remarkable film and the fact that it was at a time when records were first being made of live broadcasts. The other disasters were just not as publicized, but the Hindenburg captured the attention of the entire world.

...molecular weight is only 1/4 of Helium...
There, fixed that for you.

And before we all reach for our tinfoil hats, here's why he didn't use hydrogen: http://www.airships.net/hindenburg/disaster/myths

Sorry mate - hydrogen is diatomic with a molecular mass of 2; helium is monatomic with a molecular mass of 4 (atomic mass units). Ask your neighborhood chemist if you want to get it right...

...molecular weight is only 1/4 of Helium... There, fixed that for you. And before we all reach for our tinfoil hats, here's why he didn't use hydrogen: http://www.airships.net/hindenburg/disaster/myths

Graf Zeppelin Design and Technology

But Graf Zeppelin did incorporate one especially notable innovation, in the use of Blau gas fuel for its five engines. One of the challenges of lighter-than-air powered flight has always been the need to account for the loss of weight as fuel is burned by the ship’s engines. As gasoline or diesel fuel is consumed during flight, the ship becomes lighter, and without a means to compensate for this change, lifting gas must be vented to maintain the ship’s equilibrium. The Zeppelin Company’s innovative solution to this issue with Graf Zeppelin was the use of a gaseous fuel, similar to propane, named Blau gas after its inventor, Dr Hermann Blau. Since Blau gas is similar in weight to air, its consumption during flight did not significantly change the aerostatic balance of the ship, and so it was not necessary to valve lifting gas to compensate for Blau gas burned by the engines.

I read in a book how when the Graf Zeppelin arrived at Los Angeles on a round-the-world cruise in 1929, they were unable to refill with helium due to a ban on its sale to Germany; so a local company stepped in with a suitable replacement - 55% natural gas, 45% compressed propane. How more volatile than hydrogen that would be I'm not sure, but it definitely wasn't inert, either. People seemed to have a much more relaxed attitude towards handling dangerous materials then, and get a load of this account of the GZ's departure:

After slowly cruising down the California coast to land in daylight the next morning, Graf Zeppelin made a difficult landing at Los Angeles on August 26th, through a temperature inversion which made it difficult to bring the ship down, requiring the valving of large quantities of hydrogen. The lost hydrogen could not be replaced at Los Angeles, and the takeoff, with the ship unusually heavy, was even more challenging; Graf Zeppelin only narrowly missed hitting power lines at the edge of the field.

LZ-127 Graf Zeppelin history page.

Hindenburg paint as the cause of the disaster is a myth that has been debunked but alas still persists.

This is a good page I found with a quick Google search. Follow the links inside for in-detail information and maybe hopefully we can put this to rest.

http://www.airships.net/hindenburg-paint/

*Facepalm*

This is like arguing over whether a barrel of pure alcohol or a barrel of gasoline was the cause of a fire. Who knows? putting them right next to each other was probably a stupid idea.

I can't believe people have been arguing over why a large flammable object filled with lots of flammable gas caught fire for this long.

haha, my captcha is alcohol.

Hindenburg paint as the cause of the disaster is a myth that has been debunked but alas still persists.

This is a good page I found with a quick Google search. Follow the links inside for in-detail information and maybe hopefully we can put this to rest.

http://www.airships.net/hindenburg-paint/

In this fire at the Rochester airport, two people were injured with some surface burns

Injured "with some surface burns"? The driver suffered second degree burns on his face. Want to see what that looks like? Link (not the same person, but the same condition). There was nobody else at the station at the time. The other person who was burned was at a Burger King -- across a large parking lot and a major road, then across the Burger King's parking lot. She was flash burned.

Had this been in a residential neighborhood instead of the outskirts of an airport, it could have been catastrophic.

Yes, petrofuel burns and smokes for a while. For a while. Hydrogen burns incredibly rapidly. You can't run away from a hydrogen fire.

And there's no new evidence, especially here, that the Hindenburg burned because of its hydrogen rather than its documented explosive material skin.

Oh, for God's sake, even the Mythbusters have debunked this one. But if you'd rather a scientific paper, here you go. Here's a nice wrapup of the whole thing.

I think one of the most damning things is Bain's own video. He has to use a freaking Jacob's ladder to ignite his skin sample, and as soon as the Jacob's ladder's energy is gone, the skin self-extinguishes.

As to the Hindenburg, not a single person was harmed by the burning hydrogen which was up and away moments after the storage cells ruptured.

Well, seeing as it was up and away in a FIREBALL that melted metal in under a minute before dissipating, causing molten beams to fall on people, one could argue it was the falling molten girders that killed people, not the fireball that molten-ed the falling girders. http://www.airships.net/hindenburg/disaster/myths#advocates

You don't know what you are talking about. That doesn't make you unique because none of the "incendiary paint theory" zealots know what they're talking about either. Thermite is basically powdered aluminum and powdered rust mixed together and mixed in some goo to make it manipulable. The Hindenburg envelope was covered in layers of dope, one layer incorporating aluminum powder, and a second layer (only in certain locations) incorporating iron oxide powder. They were SEPARATE layers, not a single formulation like thermite. And the porportions used were completely wrong for thermite, even if the powders had been mixede together, which they decidedly were not. So in fact, when you burn a section of fabric treated like Hindenburg's envelope, it burns singularly unspectacularly; quite desultorily in fact.

The facts. They don't fit the ridiculous theory. It's bunk. Rocket Fuel, Thermite, and Hydrogen: Myths about the Hindenburg Crash

Oh, jeez, the "rocket fuel" BS again. Might want to read this:

http://www.airships.net/hindenburg/disaster/myths#flammable-cover

rj

It's a large inflatable ship, but not compared with other lighter-than-air ships - here's one example

Additionally, carrying one ton at 20,000 feet is pathetic, since the propulsion (and power storage) requirements weigh many times that, and if you try to go higher (to reduce the power requirements) than the payload capacity drops as well.

Nothing to see here.

Google "hindenburg survivors" perhaps? I mean, come on, there are links on the first results page! They might not give you the number of survivors, but they definitely confirm that there were some.

For the lazy:

http://www.airships.net

http://www.vidicom-tv.com/hindenburg/making_of.htm

http://www.authentichistory.com/audio/1930s/histor y/19370506_Hindenberg_Disaster_Herb_Morrison-short .html

-Alex