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I concur: Hydrogen is a "bad" fuel in terms of practicality: it's extremely reactive and it leaks easily. To make a parallel with rocket science: there are ext

by aredox 3y ago

I concur: Hydrogen is a "bad" fuel in terms of practicality: it's extremely reactive and it leaks easily. To make a parallel with rocket science: there are extremely efficient liquid chemical propellants, much better than what is in use today, like Chlorine Trifluoride, that nobody uses anymore because they are just too dangerous to work with. Or the fact that hydrogen airships will never come back: nobody will ever, ever switch from helium despite the cost and lift difference. Hydrogen has its uses (e.g. steel plants). Transportation is not one of them.

arijun 3y ago
I was curious about Chlorine Trifluoride as a propellant, and I found this quote of John D Clark on the Wiki page (hypergolic means it will ignite spontaneously): > It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water—with which it reacts explosively. It can be kept in some of the ordinary structural metals—steel, copper, aluminum, etc.—because of the formation of a thin film of insoluble metal fluoride that protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes
- wffurr 3y ago
  Ignition! - a history of rocket fuels - from which this quote originates - is freely available online and an excellent read: https://library.sciencemadness.org/library/books/ignition.pdf https://library.sciencemadness.org/library/books/ignition.pd...
dabluecaboose 3y ago
>Hydrogen has its uses (e.g. steel plants). Transportation is not one of them. Small caveat, hydrogen is still pretty useful for upper stage rocket propulsion because of its low mass and high specific impulse.

by aredox 3y ago

arijun 3y ago

I was curious about Chlorine Trifluoride as a propellant, and I found this quote of John D Clark on the Wiki page (hypergolic means it will ignite spontaneously): > It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water—with which it reacts explosively. It can be kept in some of the ordinary structural metals—steel, copper, aluminum, etc.—because of the formation of a thin film of insoluble metal fluoride that protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes

wffurr 3y ago
Ignition! - a history of rocket fuels - from which this quote originates - is freely available online and an excellent read: https://library.sciencemadness.org/library/books/ignition.pdf https://library.sciencemadness.org/library/books/ignition.pd...

dabluecaboose 3y ago

>Hydrogen has its uses (e.g. steel plants). Transportation is not one of them. Small caveat, hydrogen is still pretty useful for upper stage rocket propulsion because of its low mass and high specific impulse.