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Climate change activists disrupted the US open last night, protesting the use of fossil fuels.
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this post was submitted on 08 Sep 2023
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When people are way too smug about their wrong answer.
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https://en.m.wikipedia.org/wiki/List_of_electric_aircraft
also biofuel lol
When planes and distances get larger, hydrogen starts to make more and more sense. But I guess we won't get that far and planes will stay with biofuel and synfuel.
Hydrogen doesn't have best track record with regard to aviation.
You mean the famous accident where the thing that was completely different from an airplane was full of hydrogen and burned down for reasons completely unrelated to that hydrogen?
And no matter which therory you champion (sabotage, lighting, or static build up), the nature of hydrogen is to blow the fuck up with urgemcy.
It is one of the most dangerous fuels.
Yeah, I was talking about this one. You should check it again, because the theory about it being caused by hydrogen is currently discredited.
If by "one of the most dangerous fuels" you mean just after the more volatile fossil fuel ones, that's right. It comes just after natural gas and gasoline. It's safer than those exactly because it tends to leak from everywhere.
Hydrogen is not particularly good for aviation: it either requires a lot of cooling, or a really high pressure, and/or leaks through solid containers, or has really poor energy density.
It's a decent intermediary high energy density storage on the ground, where excess renevables can run through a fuel cell and produce hydrogen that can be stored at high pressures and low temperatures in bunker-like containers. Those don't tend to fly very well though, at most swim somewhat decently to deliver the hydrogen wherever its needed.
Hydrogen can be used in rockets though, because of the great oxyhydrogen reaction's efficiency, but you'll notice they tend to leak like crazy... which, once more, is highly undesirable for aviation.
OGM. No, the thing you can see is condensation from the atmosphere. You can't see an hydrogen leak in any reasonable environment.
Guess what? Leaking is a long term problem, and not very relevant if you refuel just before your trip. Its balance for airplanes is all dictated by the needs of a high-pressure storage against the unbeatable energy density. Up to now, hydrogen has always lost, and will probably keep losing for most airplanes, but commercial aviation is constantly pushing over factors that change the equilibrium towards it.
Condensation is one thing, hydrogen leaking straight through the metal is another.
https://en.m.wikipedia.org/wiki/Hydrogen_embrittlement
It isn't a problem if you fill up a container with liquid hydrogen right before your trip, the trip lasts less than an hour, then you discard the container and let it burn up on reentry.
It is a problem though, if you intend to fill up the same container multiple times, keep hydrogen in it for hundreds of hours, and subject it to vibrations.
Another problem is that even in its liquid state, while the energy density to weight ratio is great, its energy density per volume is pitiful:
Meaning, a plane could carry the same energy in 3 times less weight of fuel, which is great, but still need 8 times larger deposits to do it, which would mess up the aerodynamics... and would still have a high chance of springing a leak.
It's no coincidence that SpaceX is using liquid methane for its reusable rockets.
Electric airplanes are highly inefficient and not really good enough for commercial use.
Ah the moment.
That’s unlikely to change for long distance flights.
For short flights small electric planes are becoming viable already, and they will continue towards medium flights over time.
But theres no serious concepts for a battery that could compete for long flights.
That’s not to say that planes are doomed to be fossil dependent forever. But the likely solution will be a renewable high density fuel, possibly hydrogen or something easier to carry.
It’ll be less efficient than batteries on a energy in to work out basis, but once the cost of carrying the weight is considered, that will always swing way in the favour of high density fuels regardless of battery efficiency (for long distance).
Three words, nuclear powered aircraft. I see no way that could go wrong.
https://en.m.wikipedia.org/wiki/Project_Pluto
I prefer whale oil fueled aircraft
A little radiation never hurt anyone who maintains their Mach 2 velocity. Just never land and you’re fine.
Honestly I wanna see the crazy logistics of using rocket fule, since it's just liquid oxygen and hydrogen with a water byproduct
Personally I doubt electric flight will ever be viable, but that’s because we should be using trains for short flights …. Says me from an urban area
Me who grew up rural near a small city says ….. what about connections from small city to an airport where I can go places?
Me from when I worked at an investment management company and saw people with more money than they knew what to do with says ….. I just need a quick hop down the Cape to my beach house (never mind that I was never one of those people)
There will always be people like that. There will also always be places where trains are impractical.