[Qwertious]

FWIW it was about hydrogen - the Hindenburg was designed around Helium (and thus didn't have various safeties around hydrogen) but due to embargoes against Nazi Germany they couldn't get the necessarily helium, so they filled it up with hydrogen against the original spec.

[LargoLasskhyfv]

Yes. But still the paint burned first. And the hydrogen didn't explode, there was no "Knallgas". Even in all that chaos, the opportunity to mix in the right ratio with air to enable that, didn't arise. It just flared off.

One could even argue that all that flaring off generated some lift by updraft, making it crash softer, more slowly.

[maxbond]

Hydrogen is not picky about fuel air mixture; it will explode at any concentration between 4% and 74% (in air). I rewatched the footage and it sure looks like an explosion to me.

https://www.youtube.com/watch?v=OetzoO3Csj4

The thermite paint hypothesis is interesting but a bunch of hydrogen airships exploded. The Hindenburg was partly made from metal recovered from the R101. The R101 exploded on her maiden voyage.

[LargoLasskhyfv]

At 24 seconds in, that looks indeed fast. But still not what one would expect of "Knallgas" going boom.

[maxbond]

We might expect it to look differently, but it would appear that that's exactly what a hydrogen explosion looks like. By what means do you believe the camera, at least a hundred meters away, shakes?

[LargoLasskhyfv]

Did it shake by a blast? Or was it just hastily turned around, to catch the flames?

I've watched many videos about that in the past, even ones where there were overlays with 3d-point-clouds.

Not in the mood to analyze this one further. Have doubts about it being really 'real time', conversion errors, whatver.

Maybe our understanding of 'explosion' is different. By explosion I mean something coming apart fast in an instant, with a bang, things flying away, shockwave.

That wasn't that, more like a https://en.wikipedia.org/wiki/Deflagration

Caused by whatever. Very likely propagated by the flammable paint on the hull. Like a flash fire.

Which was my initial point.

[maxbond]

For sure, in my mind a deflagration is a type of explosion, but I certainly don't mean to quibble about terms or to litigate this video more than is interesting to you.

I guess for me, I don't know whether it was hydrogen leaking around the rear or thermite in the paint which caused the ignition, and I don't know whether a helium airship would've also caught fire and how disastrous such a fire would've been. But I do know that what happened next was that the hydrogen ignited and the ship blew up.

That being said I think airships are a criminally under explored mode of transit, and that the Hindenburg shouldn't be a reason to abandon it altogether. At a minimum we're much more experienced in handling hydrogen now, and modern hydrogen blimps don't seem to blow up all that often.