Well, if I can afford a flying car, I can afford a conventional car for such times. And if I’m flying when bad weather hits, I’ll land and take an Uber 
This Moller Skycar?
The Skycar family of vehicles include versions for 2, 4, or 6 persons. Capable of vertical take-off and landing similar to a helicopter, and flies from point of departure to destination much like an airplane. The Skycar has been designed to also travel at low speed for short distances on the ground like an automobile. It has fold-up wings which make it narrow enough to be usable on roadways. All this and, incredibly, it’s easy to fly!
The Moller Skycar is a perfect example of a terrible press credulously believing anything that will sell copies. The Skycar has been in development for FIFTY years. It’s been ‘months away from its first free flight’ since the 1980s. And it’s still never flown off a tether. Moller has been soliciting and accepting deposits since the 1990s.
The M400 hovered on a tether in 2003, and has never progressed past that. An application for approval as an experimental/test craft (the same thing Alef is calling ‘certification’ but is really just a limited certificate for testing and exhibition) was made in 2011, and a test flight scheduled for the FAA. The test was cancelled, and my guess is that it was a stunt to show that the plane was closer to certification than it actually was.
Moller has attempted to sell the prototypes to raise money, and has declared bankruptcy.
The M400 skycar was already closer to being a real thing in 1990 than the Alef is today. Moller is an aeronautical engineering professor and had real resources and some good ideas. He was just horribly naive about what it would take to certify and make safe a radical new flying concept. Just like people are still doing today.
Check out the fancy cover on Popular Mechanics, showing the Skycar almost ready to sell!
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Now look at the date on the cover.
I’m not going to count the ability to taxi as roadable. It has tricycle gear dinkier than what’s on a Cessna 172. And it obviously meets zero requirements for road safety. Maybe it could get one of those certs they use for golf carts, which restrict the speed to 15 mph.
Of course it’s all academic, since it’s basically a fictional vehicle.
To be fair, this is Popular Mechanics. Who, as shown, has been touting flying cars since at least the 50s (I’m sure that Exapno has cites even further back). It’s basically their whole schtick.
It’s much less excusable when CNN, etc. are doing it.
Th Skycar failed for a lot of reasons, but those reasons include technology. It needed 8 internal combustion engines and still had a crappy power/weight ratio. Control systems were poorly developed for that type of craft until recently.
Now, it looks like some of the tech obstacles are out of the way. That leaves all the other ones. But it remains to be seen if they’re surmountable.
I don’t believe there have been any fatalities from flying cars.* If there’s an exception I’m not thinking of offhand, it was someone in the production. But if there had been the press would be criminally liable. For a century they have lost their minds and forgotten everything they had printed in the past and extolled the latest claim as the Coming Big New Thing That Will Change The Future!!!.**
Tech is an issue. The characteristics of a good car are almost antithetical to the characteristics of a good plane. Anybody who can change that equation is a genius and worthy of admiration.
Tech also doesn’t matter in the slightest. Flying cars are not creatures entirely composed of tech. Humans have to be involved. Humans want to drive and fly the vehicle, the dream of personal transportation squared. A completely automated device that moves people from desired location to desired location, not merely somewhere in the vicinity, will be used but at most grudgingly accepted as a very poor substitute. And somebody in 2123 will still be getting press for their flying car idea.***
*Trying to research that is a nightmare. The term first appears in the modern press applied to cars that went “flying” off the street and crashed. As you can imagine, there were many, many, many of these, from the earliest days of horseless carriages.
**Discourse apparently will not let you use more than three exclamation points.
***I have a love/hate relationship with footnotes. I should start a thread.
Very interesting about the exclamation points. More than three in a row are collapsed to just 3. I’d not noticed that before. But you can defeat that by using the backslash escape character ahead of each !:
This:
Example: \!\!\!\!\!\!\!\!\!\!\!\!\!\!1\!\!\!\!\!\!\!\!\!\!\!\!1\!\!\!\!\!\!\!\!\!\!\!\!\!
looks like this
Example: !!!!!!!!!!!!!!1!!!!!!!!!!!!1!!!!!!!!!!!!!
I just played with Markdown’s built-in footnote feature and the preview renders completely differently to how the post appears. The preview shows traditional footnotes, but the finished product shows them as sorta-spoilered in-place popups. Weird.
Anyhow, doing footnotes via straight html code isn’t too onerous. I certainly prefer numbered footnotes to one or more asterisks, daggers, etc. That way lies madness.
I believe therte are no fatalities for flying cars simply because there are almost no flying cars, and the only one I know of that flew a reasonable number of hours was Molt Taylor’s Aerocar. But it flew like a normal airplane, with wings and a tail and a normal propeller for thrust.
As for the Quadcopter-styled ‘Air Taxis’, they’re not looking so good:
The Joby craft was going at 272 mph, with a cruise speed of 200 mph. Seems clear they were intentionally pushing the envelope with that test. In fact I’d say it’s fairly impressive that it reached that far beyond its rated speed. Looks like they have a healthy margin already. And of course it’s extremely helpful that all of these craft are easily tested remotely. “Move fast and break things” works great when you stick to things and not people.
I think the evidence suggests otherwise. Gearheads sing the praises of manual transmissions–that they put the driver more in tune with the vehicle and give them the finest degree of control (I know; I was one of these people myself until I switched to an EV). In reality, automatic transmissions dominate because people don’t care about that shit.
The automation has to work, of course. People obviously get fed up with flaky devices intended to automate their lives but in reality just make it more complicated. But you are completely surrounded by automation that you don’t even notice because it just works. You probably wouldn’t even call it automation, it’s so ingrained.
There will be exceptions. There are a few companies building “sport” craft that give the user some degree of control. They still can’t crash, for some definition of the word. But you still get to waggle the joystick around and have some fun. They’re the equivalent of dirtbikes–not particularly useful on the roads, certainly of no interest to the average commuter, but fun on the weekends.
I’m more attentive while driving my manual car then when I’m driving the automatic truck. I have to be aware of what gear I am in and my speed and plan gear changes, not just gas and brake. It’s not an issue most of the time, but that clutch powerful sucks in traffic.
I like the concept of a flying car, but like as has been mentioned, there need to be some huge problems that need to be worked out. Not ready for public, but a great grift to suck up “investments” if you are so inclined.
Nope.
In many ways, small aircraft are not nearly as practical as traditional ground-based vehicles. Flying always costs more energy because you’re always having to work against gravity as well as move forward. Weather always affects small aircraft more than ground vehicles, so they’ll either be grounded more often or more people are killed or both. Flying is not as forgiving of mistakes or bad judgement as driving. It’s a lot harder to crash-proof and aircraft than crash-proof a ground vehicle.
It’s like thinking that elevators are going to entirely replace stairs. No, they’re not. While elevators make a lot of sense in some situations (getting from ground level to the top of a skyscraper, for instance) installing stairs for a three change in elevation is so cheap, so easy to maintain, and so usable by so many people with so little training they we’re always going to have stairways even if they carry some risk themselves.
“Flying cars” will never entirely replace ground vehicles.
Let’s say you get hit by a 35 mph crosswind that wants to push you out of your lane. Quadcopters respond to this by tilting into the wind. How long do you think it will take for a quadcopter full of people to tilt into the wind, apply power, and arrest the sideways motion? How much tilt are you going to tolerate in a people carrying machine, and how fast can you allow the tilting? You are getting pushed sideways at 51 fps. If it takes 5 seconds to stop the skid, you went 250 ft to the side.
Even if you were flying behind a line of taxis and saw them all getting pushed aside, there’s nothing you could do about it pther than maybe slide over to the inside edge of your lane. You’re still going to move 250 ft once you hit the crosswind.
Comsider a microburst over a city. Intense downdrafts, followed by the air splaying out in multiple directions as it nears the ground. Every air taxi in the sky is being pushed in a different direction. How big of a separation between them do you think you might need?
Winds around built-up areas can be complex and chaotic. It’s common to find updrafts, downdrafts, vortices, all kinds of stuff. Winds change rapidly with altitude, and turbulence around tall buildings can continue for hundreds of feet over the building.
A big problem with air taxis is that they will be operating in an inherently dangerous environment. A crowded sky over a built-up area, and low to the ground, is a formula for accidents.
As a pilot you get taught how dangerous it is to fly low, and you get out of that region as fast as you can. And if you are forced to fly low, such as in pipeline inspection or crop dusting, you know you are going to get banged around by turbulence.
These things will be flying low over people and buildings, with limited endurance. That seems likely to lead to many accidents.
A crosswind doesn’t instantly accelerate you to the wind speed. Vehicles have mass and the crosswind applies a finite force; thus the acceleration is finite. Exactly how long it takes is going to depend on the vehicle, but it’s unreasonable to think it takes less than several seconds. 35 mph is 16 m/s. You’d have to accelerate at a third of a gee to do that in 5 seconds. Even the least aerodynamic box truck doesn’t slow down that fast when you let off the gas!
As for the rest, don’t let air taxis get super close to large buildings. Seems reasonable. No one’s advocating The Fifth Element here.
And if it takes half a second, you only went 25 feet. So, how long would it take? Is there a reason you think five seconds is more realistic than half a second?
Yes, the acceleration is finite. But countering it will be uncomfortable, forcing the airplane to tilt up and down constantly to maintain its little corridor. The tighter you try to keep it, the more ridiculous the flight characteristics become.
If you are used to ‘turbulence’ you might get in a jet, you have no idea what it’s like low to the ground in a light aircraft. Here’s a simulation of what airflow low to the ground can look like:
Also, airplanes gain potential energy when they climb, then convert it to kinetic energy on the way down through gliding. So climb and descent don’t cost that much. In comparison, a quadcopter needs power to ascend, and almost as much power to descend. So they are going to be flown low, especially since they will only have an endurance of an hour or so. Altitude also does not make them more efficient like airplanes, since they fly relatively slowly and drag isn’t as big a part of the energy budget.
But when you put people in the thing, you become limited by how much you can jerk them around. For example, most starts and stops in a car are on the order of .1g or less. Panic braking is pretty uncomfortable, and it’s about .3-.7g depending on the vehicle and tires and speeds. Lateral acceleration of .3g would be perceived as being tossed around in your harness, and that’s without being thrown up and down by the tilting.
So let’s limit our excursions to .1 to .3 g to prevent passengers from being sick or panicked. At .1g, accelerating from 0 to 16m/s would take about 16.3 seconds. At .3g, it would take about five seconds. But of courae it also takes time to tilt into the wind to start the acceleration, and time to recognize the crosswind and react.
A certified aircraft will not be allowed to throw passengers around uncomfortably, Here’s a good reference:
Those numbers are right around .1g. Less for lateral jerk, slight more for lateral smooth acceleration.
If we want to handle 16 m/s crosswinds and subject the passengers to no more than .1g of lateral acceleration, you have to allow the plane to be blown more than 200ft off course, meaning a 400 ft wide ‘lane’. If you wanted to keep them in a corridor 100ft wide and thus couldn’t afford more than a 50ft excursion to the side, you’d have to hit them with .5g acceleration.
To maintain a flying car in a lane with a typical road width of 13ft, where you could only slide maybe 5 ft to the side, you’d need 5-6 g’s of lateral acceleration assuming instant response. That’s never going to happen.
You can do similar math for updrafts and downdrafts to find out how big the ‘box’ has to be around your craft for safety and comfort. Any way you slice it, it’s hundreds of feet in each direction.
It’s exactly these kinds of details that make me skeptical of flying cars. The basics of upscaling a quadcopter to put a person in it is trivial. Making auch a machine safe and practical and certifiable is an incredibly large hurdle to get over.
I have a (badly out of date) pilot’s license. I know what it’s like in a small craft. The reason it gets bumpy is because the plane can’t do anything to respond to the wind in the short term. Lose some headwind and you lose lift until you can counter it in some way–a process that takes seconds or more. A rotorcraft can change the pitch of its props (and increase the power delivery) in much less than a second.
I’m not sure what you’re saying. The craft is countering the acceleration. It’s trying to fly in a straight line. If the craft did nothing, the passengers would feel acceleration from the windshear. If the craft does its job right, the passengers only feel a slight difference in their gravity vector. And not even that if the rotors can fully vector.
That’s totally absurd. You aren’t thinking through the physics of this. The craft would only need 5 gees if it were possible for the wind to apply 5 gees of force to the craft. It’s ludicrous. That doesn’t even happen in thunderstorms.
ETA: Not trying to pile on. @Dr.Strangelove just above wasn’t there when I started.
You don’t need more G than the turbulence is trying to apply. Given a fast enough control system the people won’t even feel turbulence. The machine will damp it out in the first milliseconds and fractions of an inch of motion.
This whole line of discussion is IMO silly.
On the contrary, it’s pure requirements analysis. There’s a lot we don’t know about the future of air taxis, but one thing should be determinable from first principles: How many of them can you safely stack over a city?
If the answer turns out to be ‘not many’, we can eliminate the use-case of air taxis as mass transport that could ease congestion, and start thinking about whether the industry makes sense if you eliminate that use case. They could still be useful for special events, remote factories or facilities, airport shuttles, that sort of thing.
But the first and easiest question to answer is, “How much space do they need around them to be safe from collisions under 99% of flying conditions?” For an unmanned UAV you can consider excess power, capability to yank and bank to stay in a tight corridor. For a passenger-carrying craft, none of that is relevant. All that matters is what the passengers can tolerate in the form of corrective forces.
So it coms down to whether you can actually have a , ‘fast enough control system’ in a craft full of people where the contrl involves tilting everyone violently. There can be no instant response in a vehicle with people in it.
Claiming that the passengers would feel nothing because the machine will instantly counteract the gust makes no sense at all. Aircraft counteract gusts by tilting into them. A wing produces lift in the opposite direction once it’s elevated from vertical, and a quadcopter has to tilt by increasing power on one side while reducing it on the other, so that the propwash vector is opposite the gust.
If you could somehow counteract instantly it would mean being able to tilt the craft instantly to the angle needed, and that would kill the passengers. So there is some minimum allowable time over which the aircraft movements can happen, and during that time and the time it takes for engine power to correct the drift, you will have moved some feet out of your ‘lane’.
By constraining the ‘g’ forces allowed, which that cite above I posted does, we can calculate the minimum distance the craft must be allowed to drift before it is corrected. My math says that’s at least a couple of hundred feet in the case of instant wind shear. For velocity changes that build up gradually, not so much.
Maybe this would be a better visualization: I’ve set up a challenge where you have to fly through a 5km wire mesh tunnel, and I’m going to blow random gusts up to 50 mph at you from the side as you fly through. How wide does the tunnel need to be before you’ll feel safe? You are flying along at 80 mph in a quadcopter.
Then to make it more realistic, do it with a random member of the public with you, and you lose if they throw up or are injured in any way.
Right – which is why I maintain that flying cars are not going to happen until we have some massive breakthrough in cheap energy / batteries plus extremely reliable AI to fly them (no way we let humans do it).
Taking “flying car” to mean: A flying vehicle used for everyday personal transport.
I would agree with “never” in terms of a reasonable amount to look into the future (i.e. less than a century).
But I think it’s conceivable that eventually energy is so cheap that personal transport vehicles that are incapable of leaving the ground are somewhat niche.
It’s not just the price of energy; it’s also the cost of building them. Even with massive economies of scale I think a flying car is going to cost several times as much as a non-flying car with the same passenger carrying capacity. Thoughts on this?
I’m agreeing with you, I just think we’re talking about different scope.
Within the next century, my kids, my grandkids? Yeah manufacturing a flying car is pretty expensive and the energy difference to run one versus a car remains prohibitive.
After that? We have fusion, we’re mining asteroids. Yeah it’s all a bit pie in the sky, but it was in the context of people saying “never” and “always” about certain claims.