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by bruce511 1715 days ago
>> with safer helium or something.

There's a common misconception that the Hindenburg failed because of hydrogen. That's not the case (he said confidently.)

The Hindenburg burned - it didn't explode. Hydrogen doesn't burn, it explodes. What burned on the Hindenburg was the skin, a mixture of all kinds of inflamable things including silver, dope and cotton. The same materials that made WW1 airplanes somewhat risky. When you watch footage of the Hindenburg you see the skin burning, the hydrogen escaping, and it falls to the ground, because, well, gravity.

Even then it happens really slowly - some people on the airship escaped by just waiting till it reached the ground then running away.

These days we regularly use flamable materials in transport - think Avgas, petrol, and to a lesser extent diesel and jet fuel (kerosene). The "hydrogen vs helium" issue is overrated in my opinion.

2 comments

>The Hindenburg burned - it didn't explode. Hydrogen doesn't burn, it explodes

If it doesn't contain its own oxygen it can't realistically "explode".

(edge cases involving novelty chemical reactions that go solid/liquid -> gas by some other means notwithstanding)

You need precise fuel and oxygen ratios to burn things. Burning is basically just runaway oxidation. Burn enough stuff fast enough and you get an explosion. Contain a fairly rapid burn and you can fudge the same pressures as an explosion (this is what happens in a spark ignited combustion engine). Both these require the fuel any oxygen to be in sufficient proximity and mixture to each other.

Airships, propane tanks and other sources of fairly pure gasses can't explode until after you break them and let the contents mix them with the atmosphere. Now, a trashbag full of pre-mixed oxygen and acetylene. That will go bang real good.

>When you watch footage of the Hindenburg you see the skin burning, the hydrogen escaping,

You see the hydrogen burning as it mixed with the atmosphere in the presence of an ignition source. The airship casing on its own doesn't have enough fuel to burn that energetically.

> The "hydrogen vs helium" issue is overrated in my opinion.

I agree but for totally different reasons that boil down to "people overrate risks they don't understand".

Something had to bring the skin up to ignition point. That may very well have been hydrogen, either above or below explosive mixes.

Static electricity (from a potential difference with the ground, St. Elmo's fire, or other sources) likely also contributed. Forensic analysis strongly supports leaking hydrogen from the aft part of the airship, given the nose-high, tail-low attitude and handling difficulties.

I believe a recent PBS documentary implicated static electricity.
As an ingnition source for an extremely flammable substance (e.g., hydrogen), possibly. But for the airship skin itself? I ... have grave doubts.
The aluminized dope was an extremely flammable substance.
Sources say otherwise:

A myth has taken hold that the “paint” on the Hindenburg’s skin — rather than its flammable hydrogen lifting gas — was somehow responsible for the Hindenburg disaster at Lakehurst, and this myth somehow persists even though it has been debunked by photographic evidence, scientific analysis, historical research, and even the TV show MythBusters.

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

The Mythbusters episode:

https://mythresults.com/episode70