Where do I start?
Flying cars have been a fantasy forever and probably always will be, but that doesn't keep people from dreaming about them, or even writing and publishing studies like this one, looking at the Role of flying cars in sustainable mobility.
The study compares the efficiency of a VTOL (vertical takeoff and landing) vehicle travelling 100 kilometres with four occupants (one is a pilot) to a car carrying the average 1.54 people. The flying car goes point to point without getting stuck in traffic, while the rolling car has to travel longer distances at slower speeds. The researchers compared their hypothetical flying car to both gasoline and electric powered cars.It takes a lot of energy to take off and climb in a flying car, but not as much to cruise or descend, so there is a sweet spot after which flying has lower greenhouse gas emissions (GHG) than the car, about 35km. For a 100 km trip, the flying electric car has GHG emissions that are 35 percent lower than the gasoline rolling car, but 28 percent higher than a rolling electric car.
The reasons for this are an assumption that the flying car will be running with higher utilization, that "passengers may be motivated to share rides with others to reduce higher costs expected of VTOL trips." That is a big assumption. The other is that the GHG emissions of electric vehicles go up with the carbon intensity of the electricity it is charged with, but...
...The carbon intensity of most electric grids are expected to be substantially lower in the future, as more renewable generation is brought on-line. Hence, the benefits of electric VTOLs over conventional fossil-fuel-powered road transportation are expected to grow in the future.
Notwithstanding the possibilities of flying cars falling out of the sky or crashing into each other, or the upfront carbon emissions from making such complex vehicles, the study authors conclude:
From the viewpoint of energy use and hence GHG emissions, it appears that VTOLs could have a niche role in sustainable mobility, particularly in regions with circuitous routes and/or high congestion.
Here's a thought: Instead of comparing the emissions generated by a flying car to the emissions generated by regular cars, what if you compared them to the emissions generated by no cars? pic.twitter.com/yrDurb0gv1— Doug Gordon (@BrooklynSpoke) April 10, 2019
Now I could start with a discussion about what we mean when we use the word sustainable, or point out that there are lots of ways of dealing with congestion that do not involve flying or tunnelling. As Doug also notes, "The lengths to which our society will go to avoid facing the problem of all the cars *on the ground* grows dumber by the year. "
But that's too obvious, so instead, let's start with Jarrett Walker.
1. Technology never changes geometry.
We have noted before that a surprising proportion of Americans are really excited about flying cars, that there is some pent-up demand. I have wanted one ever since I saw Supercar as a child. But they do not exist, and even if they did, there is no niche role in sustainability here, for reasons that Jarrett Walker of Human Transit has explained regarding self-driving rolling cars. Firstly, Walker has noted that technology never changes geometry. If there is a lot of congestion, then you need vehicles that carry a lot of people. To be at all useful, there would have to be a LOT of flying cars carrying 4 people, and our cities would end up looking like Coruscant in Star Wars Episode III.
2. The dangers of elite projection
Walker's other great contribution is the concept of elite projection, "the belief, among relatively fortunate and influential people, that what those people find convenient or attractive is good for the society as a whole." Flying cars are the ultimate in totally fantastical, unrealistic elite projection.
Traffic congestion, to take the obvious example, is the result of everyone’s choices in response to everyone’s situation. Even the elites are mostly stuck in it. No satisfying solution has been found to protect elites from this problem, and it’s not for want of trying. The only real solution to congestion is to solve it for everyone, and to do that you have to look at it from everyone’s perspective, not just from the fortunate perspective.
Flying cars are a ridiculous solution for the very few, very rich. It is a very small niche, and it is not sustainable mobility. If you have a problem with congestion on the ground, why not invest in transit that serves everyone.