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This is going to be the same tragedy of the commons that played out for road transport, repeated in the sky.

Everyone wants the use of a flying car.

Everyone in a flying car wants an airport at every street corner, just as long as they don’t have to pay for the land it occupies.

But…

Nobody wants to live next to an airport, or underneath a flight path. In the world where everyone has a flying car, everyone will live next to a next to an airport, below a flight path, or both.

In road transportation, rather than trying to link the private benefits of cars with their public costs, we “solved“ the inherent and fundamental conflict by putting the freeways in neighbourhoods that had the least political power.

If we had the ability to learn from past mistakes, we might try to internalize some of the externalities of flying cars, and get better results. One can dream.

I think a lot of people think they want a flying car. I posit that flying cars are a pretty terrible idea.

Single engine airplanes weigh less than a small car. They are not designed to protect the occupants from side impacts, to brake the vehicle to a stop 20 times in an hour, etc.

Today, if you fly 750 miles away and get into a fender bender in your rental car, you turn it in, fill out some paperwork, and fly home in an undamaged airplane. What are you going to do when your flying car gets into a fender bender in car mode 750 miles from home?

A flying car is bound to be a terrible (and likely unsafe) car and certain to be a terrible airplane.

> Secondly, expanding a class of vehicle that chews a lot of fossil fuel is going to worsen the already serious effects of climate change; and while short-range aircraft might well electrify you’re not going to fly at 250 knots for 1000 nautical miles on batteries any time soon.

Your average single-engine piston gets ~22mpg with a single passenger. It's not terrible at all.

Ignoring EVs for a moment, a Toyota Camry hybrid, which can carry five people in more comfort and carrying more luggage than a light aircraft, gets 50mpg on the highway.

22 mpg is not terrible only if your frame of reference is pickup trucks, whose load-carrying capabilities can only be matched by far larger aircraft with far higher fuel usage.

Furthermore, aircraft that cruise at 250 knots are not going to get anywhere near 22mpg. A Lancair Evolution, a reasonably modern four-seater turboprop that cruises at around that speed gets something approximating 7 mpg.

A Toyota Camry hybrid does not move 110mph at 22mpg with a 700mi range. Once you start moving fast the fact that it's a hybrid is irrelevant since the engine must provide 100% of the power.

I personally don't see the point of comparing a car at 50mph with a small plane at 120mph, but if you really want to, I bet that easily doubles fuel efficiency. No one flies at Vg because that's stupid, but you COULD, and then you're basically the same fuel efficiency as a car but flying in a straight line.

Even that 22mpg is not a 1:1 comparison because of that inconvenient "as the crow flies" thing. We can build more efficient aircraft in theory, but in practice the regulation gets too expensive.

Turboprop airplanes will be less efficient than pistons in general (though few pistons can hit 250 knots). A Lancair IV-P is a better comparison aircraft, hitting 335 mph at 75% power, 17.5gph, for a net of 19mpg at considerably over 250 knots.

On the other hand here is a Long-EZ that gets 40 mpg flying at over 250 mph (so not quite 250 knots but still). The actual savings will be higher since one can fly in a straight line most of the time. It also avoids congestion and ... is simply more fun than driving. Also an auto-pilot in aircraft has been a real thing for quite some time while same in a car ... is still quite pathetic. I have eaten plenty of lunches comfortably while flying a plane while I would not be comfortable doing it while driving.

Long EZ reference: https://generalaviationnews.com/2016/05/25/going-fast-on-les...

That’s impressive but it hardly sounds like a comfortable experience for passengers, and while I get the whole argument that overregulation has made light aircraft less safe, i wouldn’t get in that plane thanks.

> Yes, some of that is pilot error which can be mitigated to a substantial extent by computer controls, but it’s also a result of the lack of redundancy and hard failure modes of a light aircraft compared to a car.

Most of it is, and has always been pilot error. If we only had to worry about mechanical problems the safety record would actually look quite good.

It’s harder than driving a car due to much longer decision horizons (what you do now can doom you minutes to hours from now), much more of a dynamic environment with non-obvious hazards, and just plain higher baseline skillset and awareness requirements. All of these can and should be mitigated with technology to some extent, but there will always be that one guy who will choose to dodge thunderstorms at night.

There doesn't seem to be any danger of a large expansion of GA. All the aggregate statistics point to terminal decline.