[apendleton]

That's all undoubtedly true, but fortunately, most flights don't require the capabilities of an A380, and in fact, demand for that specific set of capabilities is apparently low enough to stop building them altogether. Even for A320 flights, most are not 3500 miles, even if the aircraft is capable of it.

If we could make progress targeting just short hops targeted by DASH-8s or CRJs or whatever, we could still make significant progress, even if it meant leaving the longer-haul flights alone, or targeting their emissions with different technologies (synthetic fuels from carbon capture, maybe).

[0xffff2]

All electric with this century's technology might work for 8-16 passenger short-haul aircraft, if that market can be created (think, many flights from various regional airports between the SF Bay Area and LA area). Nothing bigger is going to fly without a massive breakthrough in battery energy density.

[anongraddebt]

I agree. But can you explain why this is? For me, it's just a hunch.

[0xffff2]

It really just comes down to energy density and the fact that batteries weigh just as much when you land as when you takeoff, whereas you burn off most of your fuel over the course of a jet-powered flight. Those two things together mean that as you increase the size of your aircraft, batteries take up a bigger percentage of your available weight budget.

It's pretty much a smooth curve, with the breakeven point depending primarily on energy density of your batteries. Until very recently, the electric aircraft weren't possible at all. We're now at the point where two seat trainers with short (but long enough for a typical lesson) endurance are possible and in production. If you look at where battery tech is going, we can probably push that up to 8ish seats and a somewhat longer endurance within a few decades. When you look at the size of even a small regional jet, it doesn't seem likely that current battery tech is ever going to get us to the energy density necessary to make it work.

[fragmede]

Pedantically, the batteries do weigh less when depleted. Not enough to make any sort of difference, but E=MC^2. We're talking micrograms for a battery the size used here. Doesn't invalidate the point that electric airplanes can't work effectively with current lithium-poly battery technology though.

[0xffff2]

You're right, that's so pedantic it's really not worth mentioning.