[cstross]

The problem with aviation is that if you get your innovation wrong, people die.

With E-VTOL, which is presumably aiming for local-to-local flights, you have the added problem that if you get your innovation wrong, potentially bystanders on the ground die when your flying car falls on them.

It's absolutely not impossible to do it right (i.e. with nobody dying). But if you do that you need to hit existing aerospace engineering safety standards for stuff like multiply redundant flight control systems, traffic routing that avoids extensive flight over densely populated areas, and so on.

And then you discover you're competing with an unexpected combination like, say, robo-taxis feeding a high speed rail station with 220mph trains running every 15 minutes and your business model turns out to be the new Zeppelin, not the DC-3.

[Gravityloss]

For example some E-VTOL systems have six quite independent systems, each with a battery, motor and propeller. I think it helps the design to be more fault tolerant. Helicopters are allowed many things even when they are noisier and don't have similar redundancy.

There was a scheduled helicopter between Helsinki and Tallinn. It was somewhat expensive but not unreasonable. Much faster than a ship of course. It crashed, everyone died. They continued later but stopped eventually. They are complex mechanical solutions with very high maintenance requirements.