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Your first point makes sense, but if the flying cars are fully electric then I'm not sure how much of the work to make existing small aircraft totally reliable
by sievebrain 10y ago
Your first point makes sense, but if the flying cars are fully electric then I'm not sure how much of the work to make existing small aircraft totally reliable would be applicable to such a different machine.
I guess that leads on to the question of, why not start by making an electric self-maintaining self-flying Cessna?
- Nokinside 10y agoEnergy density of jet fuel and gasoline is something like 45-46 MJ/kg. All rechargeable lithium-whatever batteries have less than MJ/kg. Turboprops are efficient and reliable. They have good power-to-weight ratio. Currently electric motors are good only for things like gliders that need relatively little power.
- prplhaz4 10y agoThis link (recently on HN) provides an interesting analysis of the options: http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a-practical-electric-plane-for-nasa http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a... It seems like a fuel cell could be a viable option in the not-too-distant future, but still comes with a good number of trade-offs...
- jp555 10y agoIf self-flying taxi average flight times are 15 min, does this matter?
- jacquesm 10y agoIt does if you want to operate your self-flying taxi in an economically sound manner. All the time that it is on the ground it is not making money. Which means you'll be charging it when the number of requested rides is low, so you'll need to make a number (possibly quite a large number) of 15 minute rides before you get to recharge.
- gohrt 10y ago15 minute flight, 15 minute back to depot, 5 minute battery swap, charge batteries at the depot.
- sievebrain 10y agoYes, I know, jet fuel is one of the most energy dense things out there. But the article talks endlessly about electric power being the key to a self flying car, so I assumed the whole discussion was contingent on that being practical.
- lettergram 10y agoBlimps would also be viable. You can significantly reduce the required energy to get them to move
- outworlder 10y agoI love blimps. Even more so the semi-rigid ones. We can even get some of them solar powered now. However, have we solved all the mooring requirements? I can't envision blimps used by individuals until they can self-moor or something.
- lettergram 10y agoYou could hold the hydrogen or helium as liquid prior and post use. There's a bunch of stuff we would have to figure out to make it work, but it doesn't seem entirely impractical.