EVTOL drones to carry people

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The problem is not efficiency, range or safety. The problem is the lack of market for a short range VTOL transport. It is going to be really expensive for a small niche task, and there is a really small group of people that is willing to pay what it cost for that. So it will not justify the development, testing and certification cost.

I work with automation in the process industry. And i can tell you redundancy and power backup is mandatory in big factories where downtime will destroy products for many millions of dollars. Just on a factory making solar cell wafers as an example there is large rooms full of batteries to keep the power going in case of short power outages, and the main PLC’s and servers running the control systems are all totally redundant running in parallell synced to the same step in the program to be able to take over if one goes down without even skipping one cycle of the CPU. And the networks is running on double redundant fiber rings where you can cut the fibers 3 places before things start going down. And even the remote IO cards are often redundant. Because if the ovens or vacuum pumps stop all of the ingots are destroyed. And if the wafer saws stops mid cut the wafers are trash, and so on. Redundancy works just fine in industry. And a lot of industry’s are totally dependent on the redundant systems working when something crashes as it will do from time to time.

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That is good info from someone who knows their subject matter.
I forgot one other reason why “flying cars” (if we want to call them that) would have trouble achieving wide adoption:
The AIR BLAST at takeoff and landing will require big, open spaces (like an airport, or large, empty parking lot, or a large flat roof, for example). Nobody wants to get sandblasted with gravel.

If you were sitting in traffic in a “real” “flying car” - a real car, that could also take off vertically, the other cars would have all sorts of gravel, trash, and dust blown all over them. Same in any crowded area. Ever see the carp thrown around by helicopters taking off?

Anyway, I’m not sure why people are using the term “flying car” for propellicopters (my term), but to me, a real “flying car” would be able to take off right from the road as long as it was going fast enough for the wings to lift it off. Unless it was a helicar. Then we’re back to the unwanted wind blast.

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I just forgot - was looking up Hyundai yesterday, and saw something about them building a factory in Carolina (U.S.) or something, for building air taxis or maybe it was on Bloomberg, anyway, below I posted a link to it in the Hindustan Times:
I’m like, build a factory for a product that hasn’t been developed?
Anyway, so I looked it up.
“The taxis will be made by Supernal, the manufacturer’s air mobility division.”

Article Below - it has a good discussion of why we don’t have them in operation now. Still, it’s that same stupid theme of getting people to the airport. They hope to have them running by 2028 I think it was - wow the “factory” will be obsolete by then! People are losing their minds over AI, Bitcoin, 3D Printing, Drones carrying people, Crispr, Self-driving cars, let’s see, what else…
Hyundai to build plant in US to make flying electric taxis - Hindustan Times

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Batteries are the biggest technical challenge for electric air mobility, accounting for up to 40% of an eVTOL craft’s weight. “That’s really the killer,” Shin said.

Hmm. So for a petrol car the motor and fuel tank is the real killer, accounting for a lot of weight. Sounds a lot like «my glass is half empty» kind of thinking…

Let me rephrase: «For any sensible range and safety of a flying car, up to 40% of the eVTOL craft could be batteries. This does limit the amount of useful weight it can carry. For that reason, we are focused on improving battery technology»

Something like that

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This is one more example of the insanity currently afflicting progress. Hydrogen for energy storage is another example. The maximum you could expect to get back is around 25% of the energy put in.
With aviation, for long range, you need to carry a lot of fuel, of some sort. Liquid hydrocarbons are 100% reacted with oxygen in the air. So the ambient air is the other half of your “fuel”.

With batteries, even though the efficiency of getting back the energy put in is high, there are two major drawbacks:

  1. The battery contains only a small percentage of 'fuel" (lithium hydroxide?) The rest is structure to contain everything, separate the chemicals to prevent runaway reactions, electrodes, containers, electrolytes, etc. So a tiny fraction of the battery weight actually provides energy. And increasing that percentage is proving very difficult, if not impossible.

  2. Meanwhile, a tank of “aviation gasoline” (or kerosene for jets), though giving lower “efficiency” of return on the total chemical energy available, uses air as the other half of the fuel, and ALL of weight of the liquid fuel is used, rather than the teeny fraction of the weight of a heavy battery being used.

And hydrogen requires either a huge amount of space to store, or a huge amount of energy to compress or liquefy, and very strong (heavy) tanks to hold. The latest hydrogen airplane I saw had TWO FUSELAGES, ONE JUST TO CONTAIN THE FUEL! How ridiculous can people be?

It’s as though the social insanity currently being imposed on the population is sufficient to render even “scientists” unable to do elementary school math.

There’s an old saying: “A little bit of knowledge is a dangerous thing”.

A solution might be an efficient fuel cell that could convert the chemical energy in hydrocarbons to electricity, but again, fuel cells are not much more efficient than internal combustion engines - maybe somewhat more efficient, but not that much. Plus now you’ve added the weight of the fuel cells and there is that much more to go wrong.

Bottom line is, it will be a long time, if ever, that liquid fuels can be replaced for aviation. :slight_smile:

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Here’s another one of this latest example of “a million flies”, always set in future-tensse, of course! :):

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If it doesn’t work at a small scale, let’s build a really big one!

More “news of the future”… :slight_smile:

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Samson Switchblade Flying Car article with videos

Looks quite sketchy to me. Pretty clumsy and clunky in appearance. Note the temporary routing of the control cables to the rear elevator (horizontal stabilizer) through a gap between body components…
Everyone in the first video looked quite relieved that the pilot survived the “first flight”.
This is supposedly roadworthy, registered as a motorcycle because it has only 3 wheels… The front wheel looks way too small for road use to me. They say it can fly at 200 MPH.

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That is not a car. That thing would be competing with this

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Maybe that plus a taxi

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I happened across this article in AeroTimes questioning whether the whole eVTOL / “flying taxi” meme will ever gain traction:

Will the eVTOL aircraft project succeed or end in failure? (aerotime.aero)

Funny how Mike Barnard seems to pop up whenever there’s a need for a skeptical voice among the incessant din of irrational exuberance over new ideas for flying things.

I remember the founder of JOBY being at the first High Altitude Wind Energy Conference in 2009.
He was all about developing something like Makani, if my memory serves correctly, anyway, he had something in mind that would require propellers attached to motors. He was nice enough to have one of his underlings invite me to his place in, I think, Santa Cruz, which must be pretty nice since he is pretty wealthy. Made a bunch of dough selling camera mounts or something…

Anyway, i never went to visit his no doubt vast and sprawling estate, and he quickly pivoted to just developing and selling motors, to other AWE efforts. Not sure how successful that was - pretty limited market - but, with all those motors, he THEN went on to developing an eVTOL company.

So why do I question whether eVTOL “flying taxis” will ever catch on?

Because they are less efficient than helicopters
Because batteries are too heavy for full-size, passenger-carrying aircraft
Because they suffer from any failure being fatal within a certain distance from the ground
Because they can’t glide if they lose power
Because all the companies are chasing the same silly goal of “getting people to the airport faster” - as though that would be the only use for them. To me that limited perceived market reflects the developers’ limited thinking.

Anyway, this guy Mike Barnard was skeptical of AWE several years ago, and one of the guys associated with the old AWE forum was going hyperspastic over Barnard’s articles about AWE, threatening to “debate” him, as though he could demonstrate AWE’s impending success by just using his voice.

It was funny, but also kind of sad.

But anyway, I thought the article in AeroTime was interesting, naming the major players, all of whom are all about business plans and making agreements with the military, airlines, etc. while still having nothing operating on a daily basis.

Sound familiar?

Well it should. nothing operating on a daily basis.

Their excuses are always the same, blaming the difficulty of “certification”. To me, below a certain weight, you can fly anything you can build without even a pilot’s license. So where are the smaller versions that would be legal to fly right now? What about flying the full-size versions in places with fewer restrictions?

Sorry to say, the parallels with AWE are hard to not notice.
All progress remains perpetually in the future, all projects are just a little too big to actually do today, with occasional lamentations of “certifications” etc., but meanwhile the question is always hanging there: If you really know what you’re doing, why aren’t you doing it?

For eVTOL aircraft, they need them to be big enough, and reliable enough, to “get 4 people to the airport”, which of course has the built-in excuse of many years to certify an aircraft for such an urban operating environment. The question is, why not develop smaller ones for a single person, if it is such a great idea? There must be many uses for such a craft! And many more remote places to fly them, where they could be useful, than in cities! What about ranches? What about forestry? Crop dusting? Powerline maintenance?

For AWE, it has to be big enough to power X number of homes, preferably in a remote location where nobody can easily check to see if it is actually operating, like, say, an island. For years they always promised how many hundred homes they will power, never quite explaining why they can’t power just one home today, with all those millions of dollars.

So anyway, there’s the article. Seemed like it was good reading. thought I’d pass it along to this crowd after seeing Mike Barnard involved once again. :slight_smile:

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Well what do you know - another “press-release breakthrough” - a new idea nobody ever thought of before today, an EVTOL - no, really! Look, they even have a factory and a group selfie!

Ever notice, they all sound the same after a while?
"All (actual) progress perpetually “in the future”?
The obligatory “group-selfies”…
Pronouncements of why their same-as-everyone-else-“new”-idea is better.
“the just-unveiled prototype of which should soon begin flight…” - they even have the sarcastic 3 dots at the end of the sentence, to save us from having to add it!

OMG I just read further:
This is a local business!
Right now they are located down in Orange County, where I was previously based, before moving to this wind-powered facility at the edge of the desert in a high wind zone.

But they “plan” to do “flight testing”, “next year”, close to my current location, in nearby Victorville.
(We call it “Victimville” due to the high crime over there on “the bad side of town”.)

The Southern California Logistics Airport is also over there - a former Air Force base.
Anyway, how many companies do we now have, ALL developing multirotor propellicopter drones for carrying people? What is it, like maybe 50 companies? All with similar approaches? All making similar promises? Nothing flying on a regular basis, ever, no matter how long they go on talking about it? Remind you of anything? :slight_smile:

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Supernal SA-2: Hyundai SA-2 eVTOL will hit the market in 2028 (interestingengineering.com)

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One more “press-release breakthrough”, representing Hyundai as one of the “million flies” pursuing EVTOL.

High Points of the article:

  1. “this pilot-plus-four-passenger aircraft represents a significant leap forward in the company’s quest to bring safe, efficient, affordable air travel to urban areas.”
    ***OK, once again “urban areas” - translation: “get people to the airport faster”. This typical “pilot plus 4 passenger” version of “a million flies” can’t seem to get this “urban” meme out of their feeble heads. There is something about using the word “urban” that strikes a chord in certain personality types, usually not technical people. Reminiscent of “vertical-axis turbines” - “more responsive to the turbulent winds in urban areas!” Wheeee!

  2. “engineered for a cruising speed of 120 miles per hour at an altitude of 1,500 feet, catering to the typical city operation needs for short-distance trips of 25 to 40 miles.”
    ***translation: can’t fly very high or very far

  3. “distributed electric propulsion architecture featuring eight all-tilting rotors, ensuring a quiet takeoff at 65 dB and even quieter horizontal cruising at 45 dB.”
    ***sounds pretty familiar at this point…

  4. “By leveraging our talented 600-person team”
    ***translation: our expenses just in personnel are overwhelming and threaten to bankrupt us before any product ever hits the market!

  5. “Supernal envisions a future where the battery module can be easily replaced as technology advances, ensuring the sustainability and longevity of its aircraft.”
    ***translation: the battery weight is a major problem, as usual

  6. “While Supernal has an impressive plan and design for the S-A2, it faces challenges in its journey towards commercialization, which the company expects to achieve in 2028.”
    *** Wow, yes, “challenges” - like 4 more years of paying 600 people - sounds real promising! With 50 or more players, how big is the market for getting people to the airport faster, to pay all these thousands and thousands of people?

  7. " The air mobility industry has witnessed the rise and fall of various startups, including high-profile ventures like Larry Page’s Kitty Hawk."
    *** Yes, more failed aero-adventures from Google. Another version of the next animal struggling in the sticky muck of the La Brea tar pits! Ignore it at your own peril!

  8. “regulatory approval remains a formidable obstacle. While many emerging startups have struggled to clear this step, Supernal remains confident in its technology and is determined not to fail.”
    *** The article ends with the typical excuse they all have: “regulatory approval” - Well, as long as they are fixated on "a pilot getting 4 people to the airport in an “urban environment”, they can all keep using this excuse. Meanwhile, if they had a useful aircraft, there are plenty of uses it could have in less-populated, or unpopulated areas, especially considering places with fewer regulations, but the key is whether they actually DO have an aircraft that is useful for anything, even an unmanned version. Also, don’t forget, even in the U.S., you can fly pretty much anything without even a pilots license, as long as it is below a certain weight. But they are more comfortable basking in the safety of their endless excuses. :slight_smile:

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Just watching this old aviation promotional video by Shell, from 1956. They already had multi-propeller, tilt-wing VTOL airplanes-of-the-future, as a work-in-progress.

Song of the Clouds - Air Travel in 1956 | Shell Historical Film Archive (youtube.com)

The “aircaft of the future” segment starts at time 26:16

Multi-propeller tilt-wing airplane (“VTOL flying taxi”) is at 27:13

At 27:30 they ask: “Are the ideas outstripping what is feasible?”
answered with: “Only patient tests can show”

So even way back then, “all progress was in the future” regarding VTOL tilt-wing aircraft.

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Indeed Doug. As usual you make a fine work as archivist, among other works.
That said the time between the emergence of a new technology or, even more, its origins, and its realization on a commercial level or for certain missions when it is realized, can be long. An example:

This still leaves a lot of hope for AWE, not to mention the subject of this topic.

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At least these people had access to fossile fuels. Also they predict that the skies will be filled with aircraft. I think that one didnt age too well…

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Hello Pierre:
I don’t think fuel cells are a very good example, at least as long as they require hydrogen. Fuel cells are not efficient. Electrolysis to produce hydrogen is not efficient. Compression or liquefaction are not efficient. Storage is not efficient. Distribution is not efficient. With hydrogen-as-energy-storage returning less than 25% of the energy input, a hydrogen economy would require four (4) times the original energy production, just as a starting point. But inefficiencies multiply, so that level of inefficiency might just make any economy impossible, and we’d be back into the stone age.

There are high temp ceramic fuel cells for natural gas, but they don’t seem to do any better than existing methods of using natural gas.

So, other than a few niche applications in spacecraft from the 1960’s and '70’s, I’m not sure what all the hubbub over hydrogen and fuel cells is all about, except that policy-makers and even investors are not always up to speed on technical knowledge. Mostly they are in a herd mentality, responsive to buzzwords and a resulting perceived but unrealistic view of a hydrogen future.

Yes, hydrogen can make a great fuel. There’s a “new” breakthrough for storing and using hydrogen: turns out that chains of carbon atoms make a great carrier, eliminating most of the disadvantages of hydrogen. Who knew? :slight_smile:

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Yes, too bad we burned them all up and ran out decades ago. Now, as predicted by the same doomsayers we listen to today, we have no fossil fuels. Right? I mean, they WERE right, right? And we were “smart” to listen to them, right? We ran out, right? No more left???

I recently saw a clip of Jimmy Carter telling us there were only 30 years of oil left in the Earth, way back in, what was it, the 1970’s? Today the only argument is which untouched huge resources to prohibit drilling in, to keep prices high.

I love the idea of electric drive, even for aircraft, but if they want light weight and range, they need to use hydrocarbon engines powering a generator (hybrid drive). If you follow aircraft requirements at all, there is a minimum amount of reserve fuel (reserve range) required for safe operation. A jetliner would be in violation of FAA regulations if they did not have many miles of fuel left for an unforeseen situation, even when landing. What if they had to “go around” and try again? What if they had an unplanned diversion to a different airport? Many of the EVTOL efforts have an entire range less than the meager reserve requirements for real aircraft.

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Dynario integrates Toshiba’s state-of-the-art fuel cell technology, allowing it to operate with only a small volume of concentrated methanol solution, reducing the size and weight of the fuel tank and the overall product. An ingenious fuel feed structure realizes uniform methanol delivery, and stable output to any attached device is fine-tuned by a built-in microcomputer. Performance is also optimized by Dynario’s hybrid structure, which uses a lithium-ion battery charged by the fuel cell to store electricity.

Coming back to the subject, let’s know that the transfer to an airport takes a long time, just like urban transport. EVTOL drones for carry people may be a possibility to reduce the duration.

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OK, great. nice to know there are methanol fuel cells. That’s coming closer to what I’ve been saying for years: We need a fuel cell that can burn gasoline. Methanol and ethanol seem closer to an actual solution than hydrogen alone, due to utilizing carbon chains as a carrier. Who knew?

So will this development make fuel cells into “a thing”? Who knows? Press-releases seldom mention all the problems. As we’ve seen, out of a thousand “press-release breakthroughs”. maybe one or two come true. if these fuel cells can power a phone, next might be laptops, then cars, right? Then we can pay farmers to use fossil fuels to raise corn, which can then be converted to methanol instead of food, and people can limit the amount of land going to agriculture and try to shut down farming like they are doing in The Netherlands.

Meanwhile, thanks for confirming that new technologies that don’t seem to be gaining much traction are often very old ideas!

To me, this entire meme about “getting people to the airport faster” is the first sign of the lack of imagination and clear thinking of the current promoters of EVTOLs. When you watched “The Jetsons” (which is where this whole thing comes from - people watching cartoons from the 1970’s), how often was George Jetson & Family flying “to the airport”? Do you remember George Jetson saying “Can’t wait to get to the airport”? Did you ever see an airliner in “The Jetsons”?

What about taking you to work? to a concert? On a date? To the store? To survey your cattle? To spray your crops? To pick up your new refrigerator or some lumber at Home Depot? Why is it always “to take 4 people to the airport”??? Sounds pretty lame and unimaginative to me.

Out of ALL of the “new million flies” of EVTOL, how is it that they ALL cite “Urban Mobility” as a code word for “getting to the airport faster”? As though getting to a real source of aviation is the only goal? And what about “getting to work faster”? Why “the airport”

Don’t commuters also sit in traffic jams? Wouldn’t commuters rather fly than sit in traffic, just like people going to the airport? And don’t airports already have enough air traffic to deal with as it is?

Why is it always “the airport” These people seem to have an unheallthy fixation, as if they are mentally ill, redundant copycats, or completely lacking in imagination. They are just admitting they have a short range, and cannot serve a real purpose in aviation, other than to get you to a real airplane with real range!

Kind of like AWE “teams” always citing “remote islands” and “disaster relief” for their “million flies” of kite-reeling. Always promising to power X hundred homes by date Y at remote location Z, just as long as it remains hypothetical and “in the future”… :slight_smile:

:slight_smile:

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Just saw some more supposed “news” - but, as usual, it purports to be “news of the future”.
Hmmm… where have we seen that before?

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They talk about it as though it’s real, but can only show a rendering. Hmmm…

So far, over many decades, if not an entire century, such “ground-effect” aircraft have never caught on.
They’re usually water-based - too many obstacles on land.
I think one problem is, in aviation, height = safety, and ground-effect aircraft don’t fly high.
And then there are waves - waves can really screw things up for something traveling 180 MPH.

“This investment in our interisland transportation network will provide a renewable transportation alternative that will help keep our communities connected, support our local businesses, and build a resilient economy for Hawai’i,” said Josh Green, governor of Hawai’i, in a statement."

Here;s some more BS, from the wannabe manufacturer:
REGENT | Viceroy Seaglider (regentcraft.com)

Anyway, just as I predicted the Webb space telescope would just find more obviously-old spiral galaxies at the “edge of the universe”, “right after the big bang”, which turned out to be true, I’m predicting this “news item” is just one more example of unclear analysis, one more cart-ahead-of-the-horse example of wishful thinking without proper scrutiny. What do you think?