I agree though, planes and H2 probably don’t mix. Jet fuel should not be a priority to replace with H2. Priority should be given to static applications before trying to apply it to moving vehicles.

The main concern for hydrogen as a fuel now is the high pressures. If the pressure vessel is damaged it explodes due to mechanical forces. This is not impossible to work around. Consider, for example, that gas tanks can already be punctured and lead to fires; it takes a fair accounting of the risks to really rule out hydrogen as a fuel.

There are still dangers, but practically I'm not sure they are that much worse than a gasoline fire. There are also systems that reduce the pressures needed, like activated carbon beds. Research on them stalled mostly because there was no good way to generate H2.

You rarely by accident get a stoichiometric mix. With a slow leak into an enclosed container is usually how it happens. Otherwise there is too much fuel to O2 in the atmosphere.

People really need to stop trying to sound smart by thinking of imagined dangers. That is what stopped nuclear power, it's what's stopping hydrogen as a fuel, it's what's stopping gene therapy research, etc. Get over yourself.

> Get over yourself.

Right back atcha.

Good grief, "stoichiometric mixture" is not a reasonable person's danger threshold. The mechanical energy alone is terrifying, which was the point of bringing up COPVs.

While we're at it, let's put giant flywheels in chemical cars to do regenerative breaking. They'll probably have less mechanical energy than the titanic so they're probably no big deal, right? Right.

I'm doing as best I can. I happened to have a coworker who was involved in alternative fuels research, specifically the H2 cylinders that operated at lower pressures using a carbon substrate. But even if you don't use that you can still construct and secure the container so it splits instead of shatters and contains most or all of the debris. You can install a shield bulkhead into the car to deflect debris to the ground. You can do loads of things.

You are not original, you are not the first person to raise these concerns, and very competent people have been working on them.

https://xkcd.com/793/

They tested the incendiary paint hypothesis on the TV show Mythbusters.

The MythBusters concluded that the paint may have contributed to the disaster, but that it was not the sole reason for such rapid combustion.

As opposed to the kerosene fueled bombs we're flying in right now?

I'm not sure comparing things to close-to-wartime tech from 90 years ago is a valid approach.

You might be surprised how good WW2-era scientists were at chemistry and science.

The earlier poster has a point. Gasoline, Diesel, and Kerosene have all been studied extensively (especially in the 1930s and 1940s BECAUSE of preparations for WW2). The safety of soldiers was paramount even to the Nazis.

War machines: be they airplanes, tanks, or battleships, were all going to be exposed to enemy fire and explosions. These fuels (Kerosene and Diesel in particular) were chosen because they're extremely safe: high flash points and even higher auto-ignition points.

That means that kerosene __literally__ can't catch on fire at room temperature. You need to warm up kerosene before its appropriate to burn (Of course, once its burning it will warm up the rest of the kerosene and keep burning. But this isn't some super-explosive volatile chemical we're talking about here)

Gasoline is still safe, but not as safe as the other two (-40C Flash Point). Gasoline was safer than a lot of the other petroleum products that were investigated back then, and was still chosen as a fuel for war machines.

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The same is not necessarily true for H2. H2 will explode at any temperature (even near absolute zero).

I'm well aware of chemical prowess in that period, especially on the German part. They had a bunch of Nobel prize winners.

However, that's why I said "close-to-wartime". First of all, in case you weren't aware, the Hindenburg was supposed to use helium but due to a lack of helium in Germany (I think it was primarily due to American export restrictions), they had to use hydrogen.

I don't know of other limitations for the Hindenburg, per se, but knowing the overall German shortages of the period, I wouldn't be surprised if they had other structural issues with the Hindenburg itself, especially since it wasn't designed to be used with hydrogen.

On top of this, the Hindenburg design was from the late 20s, 1929, I believe.

If materials science, modeling, etc haven't advanced since 1929, I'll eat a shoe. If we're somehow worse at managing hydrogen after almost 100 years, I'll eat the other shoe.

The Hindenburg crew had to regularly test the hydrogen cells for oxygen content.

I'm not sure those were really the reasons for the choices that were made in most cases. Airplanes of the era used gasoline engines because Otto engines provided much better power/weight than the diesel engines of that time. For submarines, I'm not sure safety was a bigger factor than being able to use the same(?) fuel oil that the predominantly steam powered surface fleets were using, and that diesel engines provided better fuel economy than gasoline ones.

One place where safety might(?) have been a factor was that the USSR decided to power its tanks with diesel, whereas the other major combatants used gasoline engines in their tanks. I'm sure this prevented a lot of fiery demises for Soviet tank crews.

I wouldn't say paramount: https://en.wikipedia.org/wiki/Messerschmitt_Me_163_Komet

(the Komet had a tendency to blow itself and its pilots up due to the hypergolic fuel)

EDIT: That's what its called. H2 is a component of Syngas (https://en.wikipedia.org/wiki/Syngas). Syngas can then be further processed into kerosene, gasoline, or other fuels we use.