True, though it seems flexibility in body design is mostly limited by fashion. Things like the Aptera (www.aptera.com) are road legal. But I disagree it's appl

True, though it seems flexibility in body design is mostly limited by fashion. Things like the Aptera (www.aptera.com) are road legal. But I disagree it's apples to oranges. If the comparison is how to get from A to B with the highest fuel efficiency, why should cars be protected from their disadvantages? (Disregarding for a moment the chaos that would ensue if everyone driving had their own plane...) The 100mpg figure seems to apply to cruise flight at 17500ft. Given that you have to climb up there before you enjoy that advantage, it would be interesting to know what the total trip mpg is for trips of different lengths. How far do you have to go before you beat the cars in fuel efficiency?