Flying Car Dreams May Soon Be a Reality | Hacker News Reader

Flying Car Dreams May Soon Be a Reality

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29 pointsprostoalex57 comments

I'm a pilot and owner of general aviation aircraft. I simply don't understand the appeal of a flying car. It's going to inevitably be a compromise design and likely suck at both being a car and at being an aircraft.

Aircraft "want" to be lightweight and low-drag and crashworthiness (and expense) is not a significant design parameter. Cars need to be crashworthy as they are frequently bumping into each other.

I can fly into nearly any airport and have ground transportation easily available. Certainly at any good-sized airport, of which there are hundreds more than are served by airlines.

If that ground transportation suffers a minor collision, no matter, my airplane ride home is unaffected. If my flying car is damaged in a ground collision, I'm stuck finding another way home and coordinating repairs from a distance. I don't want to maintain my car to the standards required of aircraft. (Want an engine overhauled for my airplane? It's going to cost more than the median new car. Not bragging; mostly just complaining. Want the annual [invasive] inspection done? In most cases, that's going to be a $3-5K bill, minimum.)

I welcome the interest and hope some of that rubs off on general aviation interest, but I don't see flying cars as anything more practical than a gimmick.

Prediction: the media will be the only ones to make significant money from flying cars.

" 110 mile per hour airspeed"

I guess there's something alluring about pulling out of your driveway and being in the air within 10 minutes then arriving at your destination 150 miles away within 90 minutes after leaving your house. The world just became a lot smaller.

Now, what we actually get might be a lot different but who doesn't want that flexibility? Personally, i think we need autonomous vehicles before we fill the sky's with hundreds of thousands of "cars".

I get the "world got smaller" aspect; it's a big part of why I fly. Interesting that that 110 mph is an appealing speed. I guess I'd just forgotten as almost all airplanes bigger than a Piper Cub will outrun 110mph. Ours does well over 200mph and the kids still complain about how long it takes to get to grandma's house. :)

Put 110 mph airspeed into a 26 knot headwind and you'll see cars in the left lane of the highway passing you. Winter winds are regularly 40 knots or more at altitude. Into those winds, Priuses in the right-lane will be passing you. ;)

LSA rules limit the airplane to a maximum of 2 seats, further hampering the utility. (I'm trying to stay engineer-neutral and not go full Debbie Downer, but it's hard.)

Most people travel at 65mph, traffic allowing. Why wouldn't almost doubling that be desirable? Throw in the ability to fly in a direct path and it's even faster than driving. NYC to Maine, for example, is a painful drive. I wouldn't mind flying my car there for a long weekend.

I haven't looked in becoming a pilot in many years. It seemed expensive, not so convenient, and a bit dangerous. You need to spend some money to get a fast "Dr Killer"

https://aviatorcollege.wordpress.com/2010/06/25/why-is-the-“...

Doctors have killed more Bonanzas than Bonanzas have killed Doctors.

For your NYC to Maine trip, you're going to need to have good weather to get there and good weather to get back (although the option to drive back might be handy). You're also most likely going to have to navigate out from under the NYC airspace on the ground.

Private (personal) flying is expensive, not always convenient, and is a bit dangerous. You're absolutely right, though you can mitigate the risk fairly effectively (>75% of the crashes are pilot-caused or pilot-responsible at least), the cost is variable (you can rent at least to start, though that adds inconvenience), and the convenience is variable (there are ways to trade money for convenience).

Do you live adjacent to a GA airport? Where else could one expand the wings, accelerate, and take off with their flying car?

That's not really very fast at all. Most cars can easily go faster than that, the only limits are the human drivers and their pesky problems with reacting quickly enough at high speeds. Sure, no car could go that fast in a city but I'd be surprised if people were going to be happy with large amounts of people flying over residential areas so your flying car might be grounded by regulations/etc inside cities anyway.

If you want to make the world smaller than the most cost effective solution might be to enforce a common standard for networked cars and ban human drivers from motorways.

Cars regularly go >125mph (at least on the few bits of German Autobahn that have no speed limits) and while that is an insanely stupid thing to do with human drivers and their awful reaction speeds + their inability to know the intention of other drivers, a 125mph highway could be achieved via networked computer driven cars (and excluding human driving,of course) with significantly less effort than it would take to make flying cars available to anybody but a select few.

It's not very fast at all if forced to follow roads. It's a big deal if you can fly in a near straight line.

And while, yes, you can drive fast on the autobahn and similar, most of us don't live right next to a freeway and go to/from places directly on a freeway, so the average speed will tend to be far lower.

To take some extreme examples: average traffic speeds in London are below 20mph, with certain congested parts well below that.

We will never get to 125mph+ everywhere on the ground, because car drivers is not the limiting factor, but other factors such as pedestrian safety in residential areas etc.

in fully automated traffic, we can get 2x the current speed, even 3x in congested areas, and probably no traffic jams ever again.

it's not a straight line performance, but considering how 'little' is needed (capable ai-drive) compared to complete overhaul of almost everything just that people can fly around and land somewhere... much more realistic goal

This assumes the only limit is congestion, which it isn't. E.g. roads near me will soon be 20mph to intentionally make it undesirable to use them for through traffic past peoples houses, and to reduce pedestrian accidents.

In Central London, 3x means maybe reaching 30mph, but increasing parts of Central London are also getting 20mph, and while it might very well be that safer automated cars would make it viable to bring that back up to 30mph, you can't travel in a straight line or anything resembling it in the most central parts of London.

E.g. in the most central part there is a single road covering the city centre East/West (Oxford Street), which is also restricted to taxis and buses (and it's still one of the most congested roads in town). To travel the same distance East/West, you need to drive a substantial distance along heavily congested roads South/North, or drive through a maze of smaller back streets and deal with traffic lights and pedestrians haphazardly crossing all over the place, so actual speed measured by straight line between starting point and destination is a tiny fraction of the driving speed for a lot of locations in the centre... It's not uncommon for it to be faster to walk even when there isn't much congestion, depending on where you are going from/to.

So while there may be plenty of places where being able to fly won't be worth it, there are certainly also locations where "just" 100mph would still beat even automated cars by several times if you don't need to spend time driving somewhere dedicated to take off/land. This latter is the biggest caveat - if your "flying car" is really a "drivable convertible plane" that needs something resembling a runway, a heavily congested city core won't exactly be ideal.

Though saying that, even my old commutes in to London were far slower on average than 100mph when taking the bus + train, despite bus + train beating driving a regular car by a massive margin, and that was between locations with far less congestion than the centre.

I'm curious as to what the crash safety features in a flying car would even be. Emergency balloons? Parachutes? A collision at flying speeds is going to be bad for the riders, but the sudden stop after the resulting long fall will likely prove far more fatal.

How do you design for that? It seems the general trend in Aviation is that you don't; if you're falling that rapidly, things have gone so far south that you're just considered dead on arrival. (Best to get out of the plane quickly, and activate your parachute.) But I'm no pilot; I'd love some more experienced input on this. I think the idea of flying cars is ridiculously silly for the safety problems alone.

No one designs for mid-air collisions. Mid-air collisions are almost vanishingly rare outside of the airport traffic pattern. If flying cars became popular, they would increase, but still, it's a very, very large sky.

Cirrus (and some homebuilts) have the BRS airframe parachute system. Quick checking the Cirrus record, it seems like 3 Cirri have had mid-air collisions; in 2 of those, the occupants were saved by the BRS system; in the other, all aboard the Cirrus perished.

Aircraft crashworthiness is predicated on surviving an under-control arrival with terra firma, possibly after an engine failure. That is the source of the restriction on stall speed in the landing configuration of single-engine airplanes of 61 knots (~70 mph) or in the case of LSAs 45 knots (~52 mph). Shoulder belts are one of the most important factors for survivable aircraft accidents. There's a somewhat common saying, "Aircraft that crash upright and under control have survivors on board." The vast majority of aircraft crashes have zero fatalities (typically over 80% are non-fatal).

> but still, it's a very, very large sky

How are you assuming flying cars would work? Because I picture flows of "air traffic" along prescribed "air roads", not arbitrary free three-dimensional movement. Which, obviously, allows for (at the very least) rear-ending.

To oversimplify hugely, if you look at commercial aviation, that's near enough how it works. But it's all controlled by ATC who give you a height, direction and maintain separation. A flight plan must have been filed before the flight so ATC know your route. So take all that huge sky and force the planes down little corridors :)

Flying cars are much more likely to be VFR flights in uncontrolled airspace. Go where you like, tell no one, don't hit anyone, stay out of controlled airspace and in sight of ground, responsibility rests with pilot.

I'd be very surprised to see enough flying cars around to reach high enough density to raise risk noticeably outside already high traffic areas.

> Shoulder belts

My dad (AF flight instructor) relates that crew in a fighter often release the shoulder harness but keep the lap belt on while taxiing. One day, a fighter with a tandem crew taxied off the runway into the mud, the nosegear stuck in the mud, and the jet dug its nose into the ground.

The guy in front, who had left his shoulder harness on, walked away. The guy in back didn't, and had his brains splashed all over the instrument panel.

After seeing that, my dad never took off his shoulder harness until the airplane was parked and the engines were shut down.

Most ultralight / sport aviation airplanes now come equipped with ballistic parachutes. Thew work very good if you know how/when to use them.

Just wondering: How many miles per gallon does a small propeller plane fly?

My A36TN gets about 13 mpg in "go fast mode" (205-210 mph true airspeed). I can slow it down and get better than 17 mpg, but rarely do. That's for a six-seat, single (large, turbocharged) engine airplane.

My first plane, a Cessna 182, got about the same ~13 mpg at ~160mph, due to having a much worse drag profile and a less efficient engine.

Twin engine airplanes get a little more than half of that (feeding two engines, not going all that much faster). Going faster hurts mileage by about the square of the ratio of speeds; slower helps by that same ratio. (10% faster takes 33% more fuel burn per time, making specific range (mpg) 21% worse.) Slowing down 20% can often increase mileage by more than 35%. (It's not perfectly quadratic, ground ops consume fuel, and takeoff/climb is still expensive in terms of mileage.)

Obviously, headwinds hurt mpg and tailwinds help. You have more headwinds than tailwinds (mathematical fact, not just pilot grousing).

Someone has to ask: Why do you have more headwinds than tailwinds?

Simplest explanation: Take a 100 mph airplane and fly 100 miles in 25 mph winds, then fly 100 miles back.

You'll fly upwind for 80 minutes at 75 mph groundspeed and downwind for 48 minutes at 125 mph groundspeed. Your overall average speed will be 93.75 mph.

Additional factor: even a "pure" crosswind will turn partially into a headwind, as you need to crab (angle the nose) into the wind to make your desired ground track, meaning your downrange distance becomes the cosine of the crab angle, making (1 - cosine[angle]) * airspeed the effective/induced headwind.

Thanks. A bit like how a 10% investment loss in year one followed by a 10% gain in year two leaves you worse than even.

That's quite good considering the speed and that you also go more direct line compared to a car.

I got 360 miles for 27 gallons over the weekend, so basically 13 mph.

However there are modern two seated designs based on gliders that will triple that and still go 130mph.

Depends what you are flying, how much weight/passengers etc.. The sinus I fly gives me 31mpg running on car gas.. but it only carries 2 people + 20kg of cargo.

Yours is a first world answer.. In other worlds where roads are not as available & geographical conditions are complex, a flying car would be wonderful. Imagine Amazon jungle or an Island hopper or areas of extensive land with poor/constantly interrupted roads.. (All found where I currently live)

And flying cars would be easier than just building a basic road? How many people are living in the jungle but want flying cars?

Also you can already buy a cheap helicopter today if you just need to get around rural places.

There's nothing cheap about a helicopter.

An airplane wants to fly, a helicopter wants to crash. The expense for the latter comes from fighting that tendency.

Autogyros (https://en.wikipedia.org/wiki/Autogyro) are very safe and cheap, compared to planes and helicopters. Plus they are very simple mechanically, so for the third-world scenario seems a good fit. They require a takeoff and landing road, though.

But flying cars are going to be cheap enough for the jungle people?

Jungle, outback, and tundra environments have flying cars. They're called bush planes.

They land on rough, largely unimproved strips, or bare dirt, snow, or water. No, you don't drive them much, other than taxiing around the landing zone or airport, these are places with few or no roads, or far too many miles to go between spaces.

Australia, Alaska, Brazil, and similar places.

If you're interested in take-off and landing capabilities, there are truly impressive videos to be found on YouTube. With an unloaded plane and steep slope or high wind, a roll of 5-7 meters is possible.

The cars that tend to drive in such areas are heavy and robust -- Land Rovers, Jeeps, and technicals. Those make poor planes. Any aircraft subject to road conditions would shake itself to pieces.

Put landing strips where you need them and fly to them. It's far more effective. Given the terrain, it's also actually not all that more fuel-consumptive, see earlier comments about effective aircraft fuel efficiency.

Flying cars are a wrong way of thinking. They will disrupt nothing. What would "disrupt" personal flying transportation would be some kind of 95% automated flying device, that takes off and lands vertically without large propellers (some kind of contained impeller maybe) and that does not need more space than a car on takeoff and landing, so that our current road infrastructure in cities can be used. And of course it should not run on fossile fuel... If someone designes something like this and finds a way for it to be <100.000$, that might be something to write about.

I agree. Automated on demand electric drones for metropolitan areas with bridge choke points (seattle, new york, sf) and island-mainland (vancouver island) or island cluster (hawaii) transportation is where they will really shine.

Imagine a world with no roads except the ones to walk around neighbourhoods, yet a perfect infrastructure made possible by personal drones that are fed by renewable energy. There is still some place for science fiction to come real...

Counter intuitively is very hard to design a small VTOL that works on fossile fuel, it's much simpler to do it electric.

Moller is the best example after forty years and $100M and several marriages it still doesn't work. https://en.m.wikipedia.org/wiki/Moller_M400_Skycarhttps://en...

VoloCopter is a good example of what is possible today with electric powering, the big bottleneck is autonomy with current battery technology with only the pilot you get around 15-20 flight time.

Isn't this because electric drive has high power output, but that this comes at a severe cost in range?

Moller is probably most effective at having developed very high power-weight rotary engine technology. Fuel consumption is high, and the things are noisy as hell. I've watched development for over 25 years, and he's no closer to commercialisation than he was in 1989, for much the same reasons. It's nostalgic to see the occasional press mention though.

you normally need several motors or to distribute the power of the motors in several rotors that is very dificult for small vehicles

this guy did it with using several two stroke engines

http://mobile.nytimes.com/2012/03/29/garden/in-a-remote-part...

I like the idea of a flying car as a great example of just-around-the-corner technology.

I remember reading about flying cars in mid 80's from a Soviet technical journal (Yuniy Tehnik or Tehnika Molodyioji, forgot which...). It was about Paul Moller's cars and how in just 5 years we'd have flying cars around. And I thought that would be so awesome.

30 years later it is still just around the corner.

My other favorite one is "new type of batteries". Every other month there is a new type of battery that will revolutionalize the energy economy.

Not saying there haven't been improvements in these areas, or we'll never see it happen, but it is just an interesting observation I noticed about those 2 things.

One reason I imagine is those two things are easy to sell as "popular science". It is easy for anyone regardless of background, to imagine flying in a car or to imagine never having to change batteries again. Nanobots or faster integer factorization using quantum computers is maybe is not as captivating or fun to dream about.

I find the thought that Moller managed to get his flying cars positive mentions even in Soviet technical journals quite hilarious.

Flying cars have been "just around the corner" since the very beginning of powered flight, and ironically Santos Dumont floating his dirigibles up and down Paris streets and parking them up when he wanted to stop at a cafe for lunch in the early 1900s back when heavier-than-air transport was still experimental is probably as close as we got to anybody actually living that dream.

The appeal of flying cars is one of those things that seems obvious and we've had the technology to build them for decades, particularly after the invention of the helicopter and VTOL jets: trouble is the use case for them suddenly looks a lot smaller when you realise that (i) where the problem is traffic congestion, local aviation authorities are not going to let queues of vehicles try to solve it by taking off and landing in crowded areas and (ii) where the problem is few or no roads, helicopters make excellent off-road transport without the extra weight of wheels.

Try the 1810s. See my earlier comment.

Aw, a little autogyro. Those are cute.

Most people have probably seen the James Bond version.[1] That's a Wallis WA-116 Agile, of which five were built. There was a later Wallis WA-120 with an enclosed cockpit, very close to this new flying car.

Autogyros have been around for a long time, and thousands have been built and flown. They're very short takeoff and landing aircraft, reasonably stable, easier to fly than a helicopter, and not too expensive. They've never become very popular, though.

Infrastructure is the problem. Autogyros don't need much runway, but they do need some. While takeoff and landing from a road is physically possible, it's not generally allowed and does not play well with ground traffic. So you need a mini-airport. Suburban housing developments with a shared airstrip do exist; there are about five of them in the US. "Park your plane in your garage" was considered a cool futuristic idea in the 1920. But it wasn't the future that happened.

Battery-powered human-carrying quadcopters are likely as local commuting devices for the 1%. Probably coming to Beijing soon.

[1] https://www.youtube.com/watch?v=pT8Lp1SO_YU

Do you think road take-off could be made common if all the ground-cars were autonomous and would, as a system, pause (or even get out of the way) to allow air vehicles to taxi?

You would need better charting/tracking of low altitude obstacles than we have today. One 75' tower (or even telephone/power poles and lines) can make for a very bad day for the flying car and people on the ground nearby.

If this were to become common, I suspect you'd find designated sections of roadway becoming impromptu runways, but I don't think you'd find arbitrary roads being used that way.

That's an interesting thought: "on-ramps" on highways that start from nothing a few hundred feet back, with air vehicles landing on them and then merging into traffic. I don't think I've ever seen that particular image in sci-fi.

What autogyros (and other light aircraft) play even less well with are high-tension wires and radio masts.

It's surprisingly difficult to find an area that's definitively clear of these, if you're looking for an impromptu landing zone. Ground traffic doesn't mind wires overhead, but if you're flying over land, they're a poor idea to tangle with.

A very close call: https://m.youtube.com/watch?v=w-F-cBF5ZbQ

Even when you know they're there, and have ground support: https://m.youtube.com/watch?v=v5aMT9MBfZI

Right. You still need a mini-airport, a marked, hard surfaced area clear of obstacles and potholes. This "flying car" needs 200m of runway for landing. It can't hover, but it does have a slow landing speed.

There's a "SuperSTOL" aircraft that can operate from even less runway. It's a fixed-wing craft for bush pilots.[1] Much bigger wheels and tough landing gear, for hard landings on bad ground.

[1] https://www.aopa.org/news-and-media/all-news/2014/march/pilo...

Wow, that's quite the writup. I went hunting for the short roll video and instead turned up a dead stick takeoff and landing -- no power, just glide. Impressive.

https://m.youtube.com/watch?v=jeQP-H_31JQ

Plane I had in mind was a Super Cub.

https://m.youtube.com/watch?v=f7u1jzjFL8s

Bush landings, land optional:

https://m.youtube.com/watch?v=Q0fByofsZvo

> Suburban housing developments with a shared airstrip do exist; there are about five of them in the US.

There are over 600 residential airparks in the US.

The flying car has been promised for decades. Even if this suddenly becomes a reality, it's not something I want anymore.

I am looking forward to Google and others to provide self-driving cars so I can focus on owning and flying my own aircraft. Being able to order up an autonomous ride at whatever airport I land at is what I dream about now, not being cramped in a flying car which would undoubtedly be a compromise in design.

I have to agree with Sokoloff below. The problem with flying cars is, well....they fly. Which means dealing with an object in 3 dimensions, pitch, yaw, roll and all that in a product that's supposed to replace a Prius. Even in highly sophisticated jets landing and take off requires a high degree of skill. Rotary wings are easier in some regards but if they stop you sort of drop like a stone. People can't handle driving on a three lane road. I have little confidence they could navigate a 4 or 7 layer stack of lane sets.

Sadly, George Jetson is still a man of the future.

The Pal-V is on the forge for years like all projects for a flying car it will cost almost around $400k making it one of the more expensive options and it's not capable of Vertical Takeoff And Landing (VTOL)

VoloCopter is a more interresting design and almost half the price $260k, electric only at the moment only flies for 15 minutes with 1 person.

http://www.wired.com/2015/06/18-rotor-volocopter-like-flying...

Probably a less know alternative is the "roadable aircraft " PD-2 but still a high price tag of around $260k. http://planedriven.com/specs/

I am working in a one seat self-Flying Flying Car afordable alternative for around $50k and know really well the space and there is nothing with two places for less than $250k

Flying cars are really about having a personal aircraft that can be operated by non-pilots -- like a car can be. i.e. it has to be fully autonomous, because the average person can't be trusted to perform the usual functions of a pilot.

It has to get itself from A to B, communicate with ATC, land itself in an emergency, and avoid intersecting the ground or other aircraft.

What it doesn't have to be, is car-shaped, or roadworthy. If I were designing a "flying car" it would look more like a powered glider.

None of this is particularly beyond the reach of today's technology, and if the vehicle isn't shaped like a brick, it's not beyond the laws of physics either. We just need to figure out how to make reliable software...

Unless they have plans to incorporate self-flying cars into the massive campaign to roll out self-driving cars, there's no way 99% of ordinary people can be trusted to safely negotiate flying a heavy piece of equipment over populated areas.

Here in the United States, people don't like 1KG quadcopters buzzing their neighborhoods, driveways and shopping centers.

So, now a one ton piloted helicopter? Uh, seems dubious.

I hate to be that guy, but the amount of havoc commercial flying cars could create is concerning. If these things become commonplace, imagine the destruction someone could wreak. I don't think fear should ever be a good reason to deter progress, but it is something to think about if we want to go this route

Says headlines in 1950s Popular Mechanics, and annually since then...

This trope is stunningly older than I'd have thought.

https://books.google.com/ngrams/graph?content=flying+car&yea...

Starts in the 1750s, though some of that is simply justipostion of the words "flying" and "car", often with intervening punctuation.

A 1923 article: https://books.google.com/books?id=BcIrAQAAMAAJ&q=%22flying+c...

"future flying car will weigh far less than our present-day cars. The entire upper part of the body will be enclosed in an unbreakable, unburnable, glass-like substance. This is quite necessary, particularly for the ..."

And from 1810:

https://books.google.com/books?id=P_AOAAAAYAAJ&pg=PR3&dq=%22...

"likewise instructions and plans, for making a flying car with wings, in which a man may sit, and, by working a small lever, cause himself to ascend and soar through the air with the facility of a bird..."

so that would require a separate driver's license I guess.

But awesome anyway!

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