Comment Re:Supplant Niche (Score 1) 66
Disagree. A good car doesn't have down force (beyond gravity), downforce means aerodynamic drag, a good car should rely only on the force of gravity for its grip. The things that help a plane also make a car more fuel efficient - streamlining and lightweight construction. Cars have slightly different streamlining reqs due to operating near the ground, but the general principles are the same. Of course you've got wheels out there, but so do many light planes. Lightweight construction is often described as the opposite of crash safety, which is very important in cars, but with foam core composites you can have both.
As for the GP's comments: I don't think anyone really expects your average driver of a flying car to be behind the stick controlling flight surfaces; I think most people envision something more like a good quadcopter where everything is managed for you by control software that maintains position and attitude (despite changes in balance, wind, etc) or even fly preset routes / automated traffic management. People don't envision runways, they envision VTOL. They envision not a helicopter (non-roadworthy, giant exposed spinning prop), but something roadworthy with nacelles.
One big former problem with flying cars was the weight, size, cost and complexity of the sort of high power engines you needed for them, and if you needed multiple engines (quadcopter-style), then all the more problem. It pretty much ensured that your flying car would have a supercar price tag. But electrification of transportation looks to be solving that one - high power outrunner electric motors are very simple and have just ridiculous power to weight ratios. Battery energy density is still a problem (and would be even more of a problem if your lifting surface area is limited and you lose a little efficiency to your prop geometry), but it's constantly improving, the percentage rate of growth on electric passenger airplanes is even faster than that of electric cars (although starting from a much smaller starting point, mind you).
No, I'm not saying I envision the world suddenly switching over to flying cars - far from it. I'm just pointing out that the problems aren't as intractable as folk often make them out to be.