I wonder whether this is a good idea, for several reasons. First, air traffic control and congestion is already a problem in many areas. Are we in a position to handle a significant increase in air traffic? Second, does this make sense in terms of use of energy and environmental impact? Third, if "flying cars" means vehicles more like cars than helicopters and airplanes, this presumably means vehicles that can also travel on roads. Is it possible to build vehicles that both provide adequate survivability of crashes on land and that are airworthy and energy-efficient? Maybe such issues can all be solved in the long run, but at least in the short run I suspect that this is a terrible idea.