Right, now that ground transportation is close to being solved, we need to get creative with air travel. It's about 2% of global emissions and it's a much harder problem.
If we can cut 98% of emissions we'll be fine. 2% is not worth worrying about. While it may be a sexier engineering problem reality is ground transportation isn't close to being solved.
Gas cars still have huge momentum and infrastructure advatanges. No electric cars is being targeted for the mass low end demographic. We need the Honda civic of electrics.
Hybrid electric jet engines are being developed, and have real potential to improve fuel economy. A substantial improvement in fuel economy could mean carrying less fuel, which in turn improves fuel economy.
But if you’re talking about plug-in electric, the challenge is presumably battery weight versus fuel weight.
Yes, they'll still probably have to carry liquid fuel because nothing else has the energy density required. But maybe we can make this fuel from a carbon-neutral source instead of oil pumped out of the ground.