[sokoloff]

What happens when you want to have a barbeque and have 10 of your friends over? What happens in a high-rise building? Other circumstances where available roof space is less (to much less) than demand for quad-copter parking?

And quad copters are pretty dang inefficient (as are helicopters in hover mode), making the energy hurdle higher than fixed wing (or translational helicopter) flight.

Quads might end up being part of the solution (and I admit I hadn't considered them before, so thanks!), but I don't think they're well suited for covering significant distances, which is presumably where the appeal of a flying car is strongest.

[p1esk]

They will be autonomous, so no need to worry about parking: it drops you off on the roof, and flies away to a nearby charging station.

As for efficiency, yes, no simple solutions there. Note that they can still have fixed wings, the hover mode is only necessary for take off/landing.

[sokoloff]

My God. How did I miss that? Thank you for pointing out the blindingly obvious limitation in my thinking about cars vs autonomous cars. (This is a perfectly genuine response; zero sarcasm.)