No Longer a Dream: Silicon Valley Takes on the Flying Car | Hacker News Reader

No Longer a Dream: Silicon Valley Takes on the Flying Car

mobile.nytimes.com

39 pointsuladzislau54 comments

Discussed yesterday:

https://news.ycombinator.com/item?id=14183447

Another nonsense marketing piece. The image in the article is not even remotely close to a flying car. It is a ducted fan ground effect craft, no different than what NASA and USAF have worked on since the 1950's. Sure you could sort out the stability and flight automation problems with modern software. But the underlying problem to solve is one of energy storage, not aerospace engineering. This company will run into the exact same wall that every other effort to do this has. Until battery power density is increased 10x, electric flying cars will never be a thing.

> It is a ducted fan ground effect craft, no different than what NASA and USAF have worked on since the 1950's.

No, it's not. It's a modern multi-rotor, which have only been possible recently with computer control. No ducts, no (useful) ground effect. Ground effect craft have wings:

https://www.google.ca/search?q=ground+effect+craft

Ground effect isn't only a factor for fixed-wing aircraft, it also impacts rotary-wing aircraft including helicopters and the Kitty Hawk Flyer. When you fly a helicopter there is a sudden noticeable loss of lift as you climb out of the ground effect. I'll bet the Kitty Hawk is staying close to the surface at least partially to take advantage of ground effect lift, although the article doesn't make that clear.

I stand corrected, thanks.

Easy to understand summary of helicopter ground effect, with pictures:

http://www.copters.com/aero/ground_effect.html

I note that the rotary wing ground effect works to a height of about the rotor diameter, so it's not clear to me that this is a useful effect with these small rotors.

Not to mention noise. Today's cars are gratifyingly quiet. Ground effect craft are emphatically not

> Today's cars are gratifyingly quiet.

Only if you sit on the inside ;) Highway noises are extremely loud, and engine noises on local roads, especially from trucks, are painful in some places.

People may also be misled by how comparatively quiet electric cars are in an urban/suburban environment, and expect electric flyers will be similar (assuming the battery problem is solved.) This view overlooks two things: 1) a VTOL flyer would be at maximum power at take-off and landing, and at a high power level in cruise; 2) a lot of noise comes from the propellers or fans, and there is not much scope for reducing it.

It's still minimal, or at least more tolerated, compared to aviation related noise.

Why do you say ducted fan?

Or ground effect? Rotor craft have a nasty ground effect, not a nice one, IIRC.

It looks like a big multi-rotor with a saddle and pontoons. These are so simple that they'll probably work well enough.

Battery life is an issue that's not going away quickly.

> Rotor craft have a nasty ground effect, not a nice one, IIRC.

I was wrong about that. Thanks to nradov above for correcting me.

Colin Furze even made one a few months ago.

Every x months since the early nineties there will be an article about someone developing a flying car, and the inventor/ceo painting a jetsons future where riding in a flying car is but a casual experience of the future.

I'm not complaining, I just find it a truly fascinating phenomenon. In 20 years we'll be reading this same article written by someone else for the 16 thousand time.But hopefully that article will end end with "to go on sale this later this year"

The thing is, we have had "flying cars" - helicopters - for almost 100 years. Helicopters match the core functionality of a flying car: can fly, can carry 2-6 people, can take off and land almost everywhere.

So why are helicopters still relatively rare, and what is different in a "flying car" that people dream about? It's not 4 tiny wheels after all (and you can get a helicopter with tiny wheels).

* Price: helicopters are expensive to buy, and very expensive to maintain. You need about 1 hour of maintenance for every 10 flight hours.

* Fuel cost: vertical thrust for lift is very energy intensive.

* Difficult to pilot: needs professional training.

* Noise and airspace restrictions: many cities do not allow personal helicopters to fly low or land in urban areas due to noise and fear of accidents.

"Difficult to pilot" is the only area where I see significant possible improvements in the near future, if autopilot gets good enough to remove the pilot altogether.

But there is no obvious engineering breakthrough on the horizon that will improve the maintenance, energy use or noise issues. Maybe if there is a breakthrough in battery technology, then electric helicopters could improve on both the energy and maintenance costs, but that is not really up to people working on "flying cars".

> "to go on sale this later this year"

Funny that you say so, since this article says this but I don't think it makes it more true

> Kitty Hawk, the company backed by Mr. Page, is trying to be one of the first out of the gate and plans to start selling its vehicle by the end of the year.

Since the 1950s, actually. This is one of the technologies that's always 5 years in the future. "Jam tomorrow and jam yesterday, but never jam today."

The big problems are safety and noise. If "flying cars" operated in large numbers in urban and suburban environments are going to become a thing, both need to be solved.

Best guess, we can solve the safety issue. With enough on-board safety systems, pilot training, appropriate rules of the road, and mandatory transponders, we could make things safe enough. But that still leaves noise. What conceivable propeller or turbine system could lift a thousand pounds while being as quiet as a modern car? Probably none of them.

Many of the 1950s small VTOL craft ended up in the Hiller Museum in San Carlos, CA. Stop by there and see the Hiller Flying Platform, the Rotorcycle, and the VXT-8 Coleopter. All flew successfully. None could fly very far.

Lilium's VTOL, which takes off vertically and then transitions to aircraft mode, is a variation on an old idea, the convertiplane. It's a compelling idea, because winged aircraft are far more efficient than VTOL craft. It's hard to make it work well. The idea was tried twice in the 1950s, and prototypes were flown, but never worked very well. The V-22 Osprey is the only successful convertiplane, and it's not considered a big success.

No mention of Lilium, unfortunately, though they aren't in SV. https://lilium.com/

Here are a few players in this market (location:firm:product):

* Germany: E-volo: Volocopter

* Germany: Lilium Aviation: Lilium Jet

* Slovakia: AeroMobil 3.0

* EU/Silicon Valley: Airbus Urban Mobility: Vahana

* Israel: Urban Aeronautics: Cormorant

* China: eHang: eHang 184

* USA: zee.aero

* USA: Joby Aviation: S2

* USA: Kitty Hawk

* USA: Terrafugium (“legacy”): TF-X

* USA: Icon (“legacy”)

* USA: PAL-V (actual flying car)

Nice list! You really should consider merging yours with the ones mentioned in the NYT article and contributing it to Wikipedia [0].

[0] https://en.wikipedia.org/wiki/Roadable_aircraft

PAL-V is not American if I looked it up correctly.

Thanks, looks like I was wrong there indeed.

They came up on HN a few days ago. If i remember right, the TL;DR was "have you solved the battery weight problem? no? why are you wasting your time?"

It feels like history is repeating itself just like the hype over Very Light Jets about 10 years ago. A bunch of manufacturers lost a lot of money chasing after a market that didn't really exist (at least not at a realistic price).

what's more fun is to read the nyt comments section - looks like a decided lack of enthusiasm + a serious hatred of the rich and the silicon valley mindset... given the usual commenters lean heavily liberal, it is somewhat surprising to see so much vitriol aimed at this puff piece and its subject

Thanks for pointing it out. I read them all after encountering your comment. Best entertainment of the day

No mention of Ehang 184: http://www.ehang.com/ehang184

I don't know much about the company, but they seem to have got something airborne in the last couple of years: https://www.youtube.com/watch?v=1iyCgy1juHc

I just watched the Ehang video and was confused because the footage looked like they flew over Hetch Hetchy (00:16s in the video, recognizable valley/reservoir in Yosemite National Park), considering I can't bring any motorized vehicles onto the lake my dog isn't even allowed there I was surprised they could do this. Further investigation reveals most of the footage is fake https://www.forbes.com/sites/ryanmac/2016/01/08/as-drones-ta...

Wow, I didn't know that. Thanks for the link; that was very enlightening.

There is a mention of Ehang in the article. However, I cannot put this more succinctly: The Ehang is an abortion of aviation.

Instead of going into the idiocy of an autonomously piloted passenger aircraft (which will never be legal under any sane civil aviation laws), I'm just going to go over why the current Ehang 184 doesn't make any sense.

The Ehang 184 is an octocopter, with two rotors stacked on top of each other. It looks like a quadcopter with single person pod in the middle. So far, so good. However, on every aircraft ever, there are red nav lights on the port side, and green navigation lights on the starboard side. The Ehang places green nav lights in the back, red in the front. This makes sense if it always flies sideways. There are no anti-collision lights on the top or bottom, and therefore there's no way to tell when it's safe to approach the aircraft. Keep in mind, that's just the lights. There's far more wrong with this aircraft.

The battery life is 23 minutes, and the FAA requires 15 minute reserve under VFR conditions. That leaves eight minutes of actual flying time round trip. Since the Ehang needs to get back to a charging point, you're always four minutes away from your destination. Since the speed is 100km/h, the maximum possible distance the ehang can fly is about three miles, less if you account for slowing down, speeding up, and landing. Just walk it at that point.

The mere mention of the Ehang 184 in the NYT piece deserves shame. It is not a product, it has no basis in reality, and its place in history is alongside the old-time stock footage of 18-winged planes collapsing in on themselves. It is an idea so supremely idiotic the inventors and marketers of this device should be shunned.

Current FAA regulations for rotorcraft require a 20 minute fuel reserve under VFR conditions. So wouldn't that leave only 3 minutes for useful flight?

https://www.law.cornell.edu/cfr/text/14/91.151

Haha, fully agree - vapour ware, from a toy company. But they claim they'll be operating a taxi service in Dubai this July, in 3 months! Let's see...

The battery life issue (vis-a-vis reserve requirements) is common to all electric VTOL aircraft, and can be mitigated: Batteries will continue to improve (though probably slowly), and regulation seems to transition from strict specification-based rules ("x minutes reserve") to performance-based rules ("enough to ensure safe landing").

Yet, I dislike the eHang 184 particularly for the irresponsible marketing with lots of hype but few facts, the rotors placed to break your knees, the lack of redundancy, etc.

I'm somewhat more positive on the Volocopter (disclaimer: I've invested 1000 EUR via crowdfunding) - what do you think of it?

From your description, it sounds like a solid prototype: fix the lights and other typical prototype stuff, wait for battery technology to catch up, which a LOT of companies around the globe are betting on, and here you have a flying car.

> wait for battery technology to catch up

battery energy density improvements are very small and incremental. It'll take decades to go from 23 minutes airtime to something even slightly practical.

From what I gather, battery specific energy has grown by 4% to 8% per annum, so doubling every 18 to 9 years.

Applications in aviation (beyond tiny niche markets) would thus seem two to three decades away.

batteries will likely see a similar drop-off to Moore's law as they approach physical or practical limitations on energy density.

Furthermore, unfortunately, they never approached Moore's-law-speeds anyway!

Bad article, but meanwhile in Munich/Germany: http://www.theverge.com/2017/4/20/15369850/lilium-jet-flying...

Is there any company that develops something similar to an ornithopter [0] ? I skimmed over the list in the article, but couldn't find anything. The wiki suggests a greater efficiency than other methods, which with a limited battery pack would play a role in extending range.

https://en.wikipedia.org/wiki/Ornithopter#Aerodynamics

Compared to a car accident a flying car accident can create 100x damage for participating and/or non-participating passengers/travellers. The factor '100x' is just my guess, correct me if you think I am wrong. Could this be an obstacle for the future success or do you see any solution to this problem?

(This is just what I am always wondering when reading about flying cars)

More damage for the occupants, but a box that falls out of the sky has a much lower chance of hitting something meaty than a box that moves fast in the same plane as all the others. The damage zone on the ground of a flying car would be point-shaped, that of a rolling car is line-shaped. Shifting risk from bystander to occupant, that's something I could get behind.

But that's all just theory given the prototype depicted: with open blade horizontal rotors like that I could never think of those things as anything but killing machines. Even if accidents never happen, the mental image is just too powerful.

How is that a car?

I wish people actually wrote newsworthy stories to get visitors instead of making up clickbait titles.

A flying car is a silent, flying vehicle that is allowed to drive on regular streets, that anyone can purchase.

This certainly is not.

You know what is scarier than teenagers driving on the freeway? When they fly over your house.

and as others here have noted, and flying car solution would be very very loud.

Run many small fan motors out of phase.

TL;DR: rich people with big ego.

damm, then we will get a subscription model flying car!

I wonder how they plan on managing traffic in 3D.

Multipass

So there's a startup for helicopters now? /s

I really, really hope that flying cars never come to pass. Right now, when an accident happens, we know where it will happen: on the road or right next to the road (more-or-less). If flying cars were ever to become a thing you could be killed by a drunk driver crashing into the roof of your house / top floor bedroom, hundreds of feet from any road.

Disclaimer: I haven't read the article (It keeps asking me to pay money to subscribe)(which is fair to do, but I'm just not doing that right now)

I'm 99.9% certain these vehicles would be forced to fly over existing roads. And it's likely the final product would be autonomous to ensure no one could do a random fly over of your house.

The FAA would never require aircraft to fly over roads. These things (if they can actually be made to work) will be subject to the same regulations as any other general aviation. We are decades away from having autonomous flight control systems which can be certified for carrying passengers and flying through regular airspace.

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