Why Electric Airplanes Face Such a Tough Haul: Joby Edition

[@tomdchi12]

Thanks for a well-researched, well-thought out, level headed look at this. Neither an impossibility, nor an inevitable slam-dunk. The Segway was over-hyped when it was under development. It didn't live up to that hype, but you can buy one today so it didn't completely go away, and there are tons of related products like the One Wheel that derived from the underlying tech of the Segway. So it didn't revolutionize the world, but it also didn't die and disappear.

[@Kimoto504]

@Jan 6 was "Wall Street Putsch" part 2 Batteries are by far the biggest technical challenge for electric aircraft. Far more so for VTOL electric aircraft. Batteries are indeed the most pivotal factor in whether/how they succeed.

[@mytech6779]

@Jan 6 was "Wall Street Putsch" part 2 Fuel cells, which are many decades old now, are yet another over hyped tech that fails to deliver on a practical level. Notice how they aren't used in any products despite the widespread use of electrical devices. The electro-chemistry is sound theory but the materials needed for supplying reliable, economical, real world applications just aren't there yet.

[@waynerussell6401]

@Jan 6 was "Wall Street Putsch" part 2 Today Hyundai put all Fuel Cell technology on hold. Last week they stopped all research on ICE. Toyota has recently announced BEVs galore by 2030 , and again missed their deadline on a FC vehicle. Nikola continue to promulgate the fraud of FC trucks. Musk's last interview with Lex said hydrogen is not even a runner in rocketry. The problems are huge, expensive and the results are uneconomic and inefficient. Its a dead technology. Musk shows the physics make electric flight viable at 400Whkg and supersonic vertical takeoff passenger flight at 500Whkg. The new 4680 high end chemistry batteries being made now at Fremont with silicon loaded anodes and dry process coherent crystal cathodes should top 300Whkg.

[@singleproppilot]

@@waynerussell6401 I’m not sure where Musk is getting his data from. From my own calculations, the usuable energy density of Avgas when burned through a piston engine such as the IO-360 used in the C172SP is something like 4300WH/KG. And we all know a C172 is not exactly a hot rod.

[@gpaull2]

@@waynerussell6401 - Musk is nothing more than the real life version of the Simpson’s monorail salesman. Good luck if you are putting your faith all on him.

[@gneisenau89]

I always appreciate your impartial approach to this sector. As a fellow trade journalist (dietary supplements in my case) I check in on your channel not only because of my interest in aviation but also to be reminded of how to cover an industry right. You want to foster the industry's success (otherwise, what's the point of your work?) but at the same time make sure that those cases of overpromising and under delivering are brought to light. Thanks for the excellent work.

[@AVweb]

Thanks. Appreciate the kind words.

[@77thTrombone]

I hesitated to watch this video, as I was concerned it might be a little too "pandering." Upon reflection, I realized, "Hey- it's Paul B, after all." No regrets at all. Actually, this the sort of assessment that _needs_ to be out there.

[@clivemccall3714]

,3,333

[@kentd4762]

Well said. Paul's balance is always welcome.

[@barbermot]

That's in "aviation dollars" as in what you tell your spouse vs what it actually costs.

[@williamharn9048]

Exactly

[@Croz89]

Should it be "general aviation dollars"? Because in the commercial space it almost seems the opposite, massive sticker price that gets negotiated in half when an airline makes a nice fat purchase.

[@M1911jln]

I admire these companies for 1) their incredible marketing and 2) their ability to make these claims with a straight face.

[@jebise1126]

why? its nothing new. what about snake oil salespeople of 200 years ago?

[@andreww5773]

Joby wants to build a new technology that's fast, cheap, reliable, safe, built at enormous scale, being all (most) weather capable, and adhering to regs, while also likely trying to rework ATC systems to allow this type of thing. Oh, and make a profit. I suppose nothing is impossible, but that's a hell of a tall order.

[@Kc12v140]

While I wish them luck… your 100% accurate on this. At a minimum, they might succeed to the extent of having a small test fleet running loops, but they will burn through so much money doing it. Eventually investors will cut their losses and they will be relegated to selling their multicopters to the general public at the tune of 15-20 per year and will die a slow death..

[@robgrey6183]

They are obviously angling for billions in subsidies from taxpayers who will never benefit from their electric toys.

[@tomc.5704]

The profit part is going to be very hard. Their chart at 19:35 wants $90 for a one way ticket. That's probably assuming their aircraft can be quickly and cheaply manufactured while meeting all requirements. Who is going to pay $180/day for a round trip commute? Certainly not a billion people every day. I'd guess their consumer numbers are in the 10s of thousands, not the hundreds of millions. And I guess sure, it gets better if you carpool and split that cost 4 ways. But first this eVTOL needs to exist and be safe and be approved, and that's not a guarantee. I'd say expecting it to come online within 15 years is far too optimistic, and when it finally does the price per ride is going to double.

[@M1America]

I dont think the issue is technology. The technology is all there. The issue is that they have to bring everything together in a way with enough reliability and redundancy to operate safely.

[@fredygump5578]

People make careers out of pushing pie in the sky ideas that never have a chance. I hear it's profitable!

[@TheBlahblahblahhh]

IDK if it's literally just you or if you have a team helping you but either way ... This is absolutely incredible content. You hit a ton of salient points and it's clear you've done a ton of research. Thanks so much for putting this together!

[@JoshuaTootell]

It is a team.

[@paulbertorelli9044]

@@JoshuaTootell Ah, were it so. All of these videos were a band of one: me. They have more staff now, but lack the lunacy to wade into black pits like this. 😃😃😃

[@kurtpena5462]

It's the greatest thing since the Rotodyne! It's an ELECTRIC OSPREY being build by A RIDE SHARING COMPANY!!! What could possibly go wrong!

[@helicopter7730]

Great explanation, and as electrical engineer of many years with experience in lithium batteries, 3-phase inverters and similar high power electrical equipment, these adds for electric planes make me laugh. If anyone thinks a practical electric plane capable of carrying passengers and payloads will become a reality within the next 30 or so years, all I can say is keep on dreaming because we have a long long way to go before battery technology gets even close to the energy provided by 1 litre of kerosene ! I'm sure it will happen one day in the.............. distant future.

[@dungareesareforfools]

Agreed - and my concern would be of range reliability, which is of course absolutely safety critical. With a liquid fuel you can determine remaining energy with absolute certainty, with a battery it’s more of an educated guess.

[@jaysmith1408]

@@dungareesareforfools oh how well I’m familiar with that concept. I have (though now effectively replaced by a ford explorer) a Nissan leaf. I go to work in the morning on a full (80% charge). It says I can go 40 miles. I leave the city limits not two miles away, and it says, “ya know what? I only want to go twenty miles today”. Factor in the 20% minimum, and I have to recharge in the next town. Current batteries are extraordinarily temperamental and in a safety critical application, dare I say unreliable.

[@calyodelphi124]

You really set the golden standard of journalism with these AVweb editorials, Paul. I love that you take such a level-headed and rational approach to a topic that can (and should) be thought about rationally.

[@buildmotosykletist1987]

@Calyo... : You'll be redundant before they get off the ground but meanwhile you can have fun :-) We have a drone here that surveys our crops. We program it and walk away. When it lands I get a text message it has landed so I can log on and check the results. It has only crashed once ;-( is there an irony icon?

[@calyodelphi124]

@@buildmotosykletist1987 Tbh that's the kind of menial chore that automation is absolutely perfect for. That drone is perfect for what it's been purposed to do, and it always amazes me (in a good way!) to see farmers being at the forefront of new technology in the ways it's meant to be used. :D But until the FAA approves the use of drones as heavy as GA aircraft, I don't think you'll be automating away the job of crop dusting anytime soon. You'll still need good ol' part 135'ers like me (eventually) to dive bomb your crops with stuff. ;)

[@ChriscsHunter]

The public can now view this aircraft flying at Marina Airport just south of Santa Cruz on clear mornings. In flight it is extremely quiet and barely noticeable, and it became completely inaudible against other aircraft that were flying around the area. It appears that there is no pilot inside and is controlled remotely. Very exciting aircraft and I hope you make an updated video as more information comes out.

[@adam872]

That was fantastic. No hyperbole (negative or positive), just sober factual analysis. Loved it.

[@shorttimer874]

Mom was an engineering aid at Boeing starting about 1960, plotting out wind tunnel results by hand. She had the neatest fine tip pens I've ever seen. I got to do a walk through of Boeing's SST mockup, and browsed some of the Dyna Soar materiel she brought home. So I've been an outside observer of aviation news all my life. I've never experienced anyone making the information so approachable to an outsider in as entertaining way as Paul does.

[@stcredzero]

If the flight profiles will deliberately avoid climbing as much as possible, why not power the climb with a belly umbilical cord?

[@StarlightSocialist]

Good question! There are two major benefits to this sort of thing. One is vehicle range, it starts the flight with "full tanks" PLUS the potential energy of however much altitude you can gain. The range improvement will actually be slightly more, compared to starting on the ground, since climb power is disproportionately expensive in terms of energy consumption. All batteries have "internal resistance" and the more power you draw the more the battery heats up, and the energy consumed in heating is 'lost' since it can't perform useful work. All batteries have a rating in amp hours or watt hours but this is measured at a specified current draw. This brings us to the other advantage of the 'extension cord" idea. High draw is _murderous_ on the cells. The cooling system has to be able to pull heat out of the batteries as fast as it's generated, otherwise the cell goes from a chemical reaction that produces electricity to plain old chemical reaction. It's usually pretty spectacular. If you restrain the batteries pyrophoric tendencies the high draw _still_ kills them, it just takes longer. Although through gradual loss of capacity. So now that we've covered the obvious advantages, what are the obvious drawbacks? For one, there's going to be a maximum length of cable that the aircraft can lift. If the cable weighs one pound per foot and you have 1000 pounds of payload available then you can get to 1000 feet of altitude before you detach. Not stellar, but not insignificant either. Now imagine a thousand feet of extension cable falling from altitude. Engineering can help make this prospect less dangerous to people and/or damaging to the cable (helium balloon, parachute, high drag device, etc). It can probably be made practical, but there's nothing to be done of making it seem less crazy of an idea. The 1000 feet example is just for demonstration and the one pound per foot is completely arbitrary. The cable could weigh much more or much less and both have their tradeoffs. The cable has to carry the power you need, no getting around that. You can use the same trick that high tension power lines use and transmit the power at very high voltage, that let's you use smaller wires. But you also need more insulation and more weight in the vehicle to transform the power into whatever voltage the motors use. You can transmit the power at the usage voltage but the umbilical would need to be beefy. There are plenty of variations on this extension cord concept. Beam the power to the aircraft as microwaves and equip the vehicle with a rectifier-antenna. Have the big ol bank of capacitors that supply power as the aircraft climbs and jettison them when depleted. (Again, parachutes). Provide the power in the form of kinetic energy by catapulting the aircraft into flight. Or anchor a blimp above the launch site and winch the aircraft up to altitude. Or use "active support". Lots of ways to accomplish the same thing, raise the vehicles energy state without adding mass that it has to carry.

[@CaptMikey-vc4ym]

100% true. Modern aviation has turned its spirit upside down. Everybody said, as you observed, "If man was meant to fly, he would have given the Wrights wings" or something like that. You are correct, the challenges of electric flight are monumental. We are back to the same old power for flight problem. The big thing the Wrights did was to develop a power plant just barely able to lift the Flyer. It was internal combustion, and it was developed into something useful in something like 15 to 20 years. The big developer was the military, the money bags. Energy density is a big limiting factor, but the performance of the electric motors, in some respects has been ignored, in terms of efficiency and heat. The rotation of the armature gets power from the field of the windings. But the field also creates drag which results in heat and big losses of total power and electric power consumption. Just the things that are of the biggest concern to aviation. There are ways to reduce this field drag which have largely been ignored. Let's get back to the "Spirit of the Wrights", be aware of the problems, but don't let them stop you. It seems like the American attitude has become "No, we can't". Let's see if we can turn that around.

[@RadioMarkCroom]

Thanks for a thoughtful and seemingly balanced presentation on this important topic. Though I live and work in the Northern Plains of the US and will likely not see these in service in any of my markets in my lifetime, I want to see this technology succeed. My sense is that the battery weight issue -- kwh/kg -- is the big uncertainty that will be the difference between whether these will be practical or not. The rest of the technologies are just extensions of what is already in service (VTOL airplanes exist, multi-rotor small aircraft exist, composite constructed airframes exist, etc). But light enough batteries? Not quite sure they exist yet. New tech probably needed and we're clearly running up against the laws of physics as we understand them. It will be very interesting to keep an eye on this sector and particularly on Joby as they are powerfully motivated to succeed in this brave new world.

[@leftcoaster67]

Great work Paul. Simple, rational. Not closed minded, but not a sucker for investment dollars either.

[@johnwighton]

Thanks Paul. Very interesting and refreshingly open and honest. We are in the business - developing UAM, UAV, and find the timelines (hence budgets) to be total fiction, stated only to show a light at the end of the tunnel. Unbelievable that investors swallow the BS coming from many of these companies.

[@chicagorandy]

As a 73yr old curmudgeonly geezer, I have seen many the 'pie' go by in the sky with VERY-VERY few of these concepts making it to final production and market success. Your report has quite clearly shown us the pros and cons of this type aircraft. Most everyone agrees that the battery remains the weakest of the links in this e-power chain, both on the ground and in the air. Thank you for an unbiased and information packed study.

[@chicagorandy]

Those of us who live in a major city well know how many Uber drivers get into crashes. I can't imagine the carnage when the sky starts to fall too.

[@joetroyner]

I love that you can deliver an intelligent, nuanced commentary mixed with "driving across the country looking up the assholes of horses."

[@Bravo21]

That glass of reality may not be tasty to some, but it's much needed with all the claims and promises we keep hearing about the Electric revolution. I would love to see it happen, but will it with current battery Tech?

[@petervanderwaart1138]

Vertical takeoff seems a strange place to start for an endurance-limited aircraft.

[@AVweb]

But without it, UAM is a non-starter. That's the other side of the distributed electric propulsion coin. You can put that power anywhere, easily. And a lot of it. You just can't power it for very long because of battery limitations.

[@williamharn9048]

No kidding. Using up 70 percent of your power before moving forward. They have a long uphill climb 👍

[@jebise1126]

sao paulo has the most helicopters per capita apparently... so clearly there is option for that. short hops are probably the best option for such aircraft actually.

[@matthewprather7386]

@@jebise1126, I wonder if this statistic depends on a large wealth and income inequality... If so, pass.

[@jebise1126]

@@matthewprather7386 of course.. but lets face it this vtols wont be for everyone anyway. they are selling it as a such but it will never happen. well... possibly they could work as city air ambulance.

[@Deltarious]

Just to add, Harriers have near unified flight controls, but zero fly by wire assistance. The throttle has a nozzle position lever just to the right of it, which is typically set into the full vertical position (82 degrees due to aircraft balance) and left there for most VTOL operations (things change when STOL is thrown into the mix), aside from that it flies extremely similarly in terms of control inputs as long as you remain inside the envelope. Pitch roll and yaw all work as you would expect them to, but are a lot more sluggish and significantly less stable, you add power to climb and reduce it to descend and use pitch to adjust speed, exactly as you would in a regular landing controlling for AoA.

[@DeereX748]

I wish I could give this video nine more thumbs up. Paul has a way of knocking the starry-eyed attitude out of those who would profess they have a miracle coming, and this video is no exception. My take on the whole electric airplane concept is that battery technology, good as it has become over the last 15 years, still must make a quantum leap in the energy density and longevity (including time to discharge and recharge time, as well as lifespan) realms before becoming a viable power source for aircraft. Even if it proves itself in the energy density, the longevity and cost of replacement at end-of-life has so far shown itself to be short and expensive in the grand scheme of its automotive use. A ten-year old Prius isn't worth what the cost of its battery replacement is, and look at the guy who just blew up his Tesla, rather than pay 2/3 the cost of the car (a 2013 model) to replace his batteries. I'm convinced I'll never see or experience electric flight in my lifetime. Of course, I'm almost 70, but I'll stick to internal combustion until my wings have feathers and I'm wearing a halo and toting a harp..

[@jannepeltonen2036]

TBF, the guy blew up his Tesla, not because the battery replacement itself would've been absolutely necessary, but because of Tesla's company policies: someone not Tesla had made a modification into that car before the guy bought it, and Tesla said they want him to buy a new set of batteries because of that before fixing the problem...

[@DeereX748]

@@jannepeltonen2036 Even so, unless and until battery cost goes down significantly, electric cars are like TV sets, it's almost cheaper to buy a new one than fix the old one. The buyer of a used electric vehicle is paying a premium price, knowing they will bear the cost of a battery replacement eventually, unless they unload the car on someone else.

[@mytech6779]

NiCads have the needed power density (Some constructions can give a 15 minute full charge or discharge.) and can take full discharge, but they are short on energy density and overall lifecycles.

[@waynerussell6401]

You are ill informed (from the vested interests). And the environment suffers. Current battery technology from multiple sources outlasts ICE. BYD have cheap one million kilometre LFP cells and CATL one million mile LFP cells that go into Tesla low end cars. Dahn the Tesla battery consultant has published a white paper showing every battery manufacturer how to make a 2 million mile cell. Tesla has the lowest warranty claims of any US manufacturer. Many companies offer 8 year warranties. That Finnish car had an unlimited mileage warranty. The Fins have a reputation for crazy (though they removed the 'faulty' battery and motor which have high resale value). The car had been used in very harsh cold conditions. The records for version one Model S battery life show 300 000 miles is more than typical. Current chemistry is well suited to EV use with charge times faster than humans can recharge with recommended rest times on long journeys. And costs continue to dive, current CATL LFP cells at US$60 kWhr. manufacturers kzbin.info/www/bejne/poC0goetjtCaZpo insideevs.com/photo/5051317/tesla-model-s-x-battery-capacity-retention-per-distance-traveled/ kzbin.info/www/bejne/hp28gndveLKqi80 electrek.co/wp-content/uploads/sites/3/2021/08/Screen-Shot-2021-08-09-at-9.45.19-AM.jpg?resize=1600,220

[@mytech6779]

@@waynerussell6401 If you had a real education in this specific engineering topic would would know batteries aren't measured in miles. Only complete cars can be measured in miles and we are not even discussing road vehicles. Secondly, you would know that mean lifetime of any component (using any unit) is a low value statistic without an accompanying standard deviation, consideration of the magnitude of impact a failure will have, and consideration of the mode of failure (sudden, gradual, with or without early warning signals, etc)

[@robertling9872]

Thank you Paul for sharing your views. Complex innovation always happens when everyone looks the other way. Let them surprise us all and open a new market of air-transportation.

[@abidfarooqui-sla3301]

A reasonable and open minded analysis of electric aircraft and specially of this specific section of eVTOL urban mobility. Good job. You didn't touch on how the autonomous version will behave with traffic control but that I think can be figured out and depends on standardization to an extent. The main problem still is energy density and battery technology. So many disadvantages there in aviation that are so hard to overcome and this technology has no direct relation to aviation. Its an energy density problem with batteries and the solution if any will come from elsewhere where numbers and volume are huge compared to aviation

[@yyyyyeeeee4060]

This channel has the best organized an impartial information on aviation, and out of all topic specific channels on youtube, this one is the best. I wish there was an AVweb for all of my interests.

[@skenzyme81]

All Joby has to do it announce they're gluing on some Tamarack Active Winglets and Paul will change his tune. 😉

[@lcprivatepilot1969]

Doubt it

[@akschu1]

Paul, good video, solid data. In some ways 6 motors is way more complex, but in other ways, it's much simpler. From a software perspective, it's really not that hard. In the camera drone world, they are extremely stable and reliable able to track a target through trees. Scaling this tech to a simpler point to point system at full scale isn't that hard. Here is the rub: The combination of automation and humans. Most airline accidents these days are because humans don't manage the automation correctly, or the automation is designed to help humans not replace them but does a poor job. This handoff is the complex part along with the idea that we have human backup. If there is no handoff, and if we know that a human can never fix it, then the appropriate level of redundancy is built in, validation and testing is performed, and the accident level becomes a function of actual accidents (things you can't control) and the reliability of software. Look no further than space-x to see what full automation in a well designed system can get you.

[@TDCflyer]

Remember Segways? There was a presentation of "soldiers" advancing on segways with their guns up - they looked like they were taking a dump while unsuccessfully trying to shoot something. Classical case of "When the only tool you have is a hammer, just about anything looks like a nail to you" Same thing with multicopter drones, once the control units were working reasonably well. Now everybody and their grandmother is suddenly supposed to have to go places in drones, and only in drones.

[@MikeAltogether]

I think this may be one of my favorite comments here. We've just always taken for granted that people will always want to go farther, faster, and easier, but the world doesn't look like it did in 1900. Thanks to the internet, and perhaps more importantly, the amazing supply chain we have these days, there aren't many reasons to travel to a lot of places. There will always be a need for long distance travel, but we basically have that solved today. Short distance travel is accomplished by cars and EVs will fill that role soon. But the middle ground, day trips that take several hours now, I just don't see how these aircraft fill that role. Anyone traveling that distance either needs more cargo load or needs to get there and back much faster than these can provide. The only exception might be people who commute 30 miles or more for work. But any benefit these aircraft offer for that task could be outweighed by rail frankly.

[@lsx001]

I've always enjoyed Paul's research videos. As a CFI that worked in automotive manufacturing industry, and currently working in an airline/MRO, I'd like to point out some discrepancies regarding the manufacturing portion. Automation, as how Paul used the sense of the phrase, means Lean Manufacturing. The goal is to reduce human variation on quality by replacing some or all human with machines. Automation is not the end, rather an means to an end. Meaningful endeavors of auto industries trial to reduce human variation did not start until after the B-24s that were made in Willowrun dropped their bombs on Japan's homeland, ie, the Toyota Production System, born out of the ruins of bombed out Japan. With a large investment from Toyota, and their experience in automotive manufacturing, I'm quite excited to see how Toyota and Joby can improve quality and reduce cost on aviation manufacturing as well.

[@cutl00senc]

Great commentary Paul! As someone who inherited a love of all things mechanical, I will never turn my back on the ICE. But I love fresh air, clean water, and silent evenings even more. The future was imagined to be quite different in 1950 than it has progressed to be. Our love of cheap gas and horsepower and joy riding all over America has cost us our imagination. We have a lot of catching up to do.

[@Paul-hr6yg]

12:30 12:39

[@DanJohnsonAffordableAviation]

ANOTHER great Paul Bertorelli video. Good writing. Good production values. Excellent message. Go, Paul!

[@hedonismbot1508]

I remember reading an article about some prototype electric plane, doing the math with its range relative to an average gas-powered plan in its weight class, and calculating that we'll need roughly a 5x improvement in battery energy density to let electric planes get up to parity.

[@PilotA51]

If true, that's good news. Lithium-Ion energy density nearly tripled between 2010 and 2020 and there's more R&D going into battery tech now than ever before. I'm optimistic that it will happen faster than most people expect, as it did for EVs. I'm a very happy owner of a 2014 Tesla Model S 60 and am impressed by how much EV range has gone up and cost gone down since then, and excited to see continuing advancement.

[@shaynegadsden]

@@PilotA51 not sure where you got that idea lithium tech has gone from about 100wh/kg in 1991 to the best of about 280wh/kg now so not even a 3x increase over 30 years

[@kipter]

@@PilotA51 lions aren't allowed on aircraft for fire concern reasons. Not sure how they would fix that.

[@PilotA51]

@@kipter There are cargo restrictions for that reason, but the Boeing 787 for example is designed with Lithium-Ion batteries for the APU. It had a relatively minor fire issue caused by a cell manufacturing defect a couple years after it entered service, which was resolved without having to remove it from the design. Pipistrel has two electric aircraft in production that use LiPo batteries. Some chemistries are less likely to go into thermal runaway even when punctured, but with tradeoffs like lower energy density. As long as the battery is manufactured to high standards, properly cooled, not overcharged, and protected from external damage, the risk of fire is extremely low, likely lower than with a gas vehicle.

[@zosoachilles]

This is a classic Paul B. video. Superb writing, reporting, graphs, comparisons, even the smidge of skepticism is relatable by the viewer. I met you at Deland, come see a proper Vashon Ranger wrap at SnF 22'.

[@bjs2022]

Great research and presentation, as usual. I learned a lot. Thanks.

[@davidkreimer2970]

I loved this video too. But what was not mentioned in it is that the big driver in this whole battery powered airplane development is that their operating costs are a tiny fraction of our current (no pun) carbon based systems

[@braincraven]

Paul such a well written point of view. I love how you point out that under the surface things are more complicated than what they seem.

[@SwissPGO]

I live in the beautiful country side of Switzerland where public transport is almost everywhere. From my home, it takes me a 10 minute walk to the nearest train station, another 20 minutes to the next station where I can hop on an intercity train, and then onto the 300 km/h european high speed train network. Why spend billions inventing flying taxis, if the technology for efficient transport exists outside the US? Just implement a solid public rail system... no batteries required. I liked your analysis- but I think investors should put their money getting things rolling, and not flying, as it is more energy efficient.

[@Croz89]

I don't think air taxis will really take off in most of Europe for this reason (pun intended). But I can see it being useful in more remote or spread out areas, the Australian outback or rural Canada. And perhaps in some cities which tend to sprawl, like in the US.

[@SwissPGO]

@@Croz89 Yes, possibly australia rural areas are not yet covered by regular public transport lines, but is low density areas like that, there will also be very few demand for such a service. No need to vertical takeoff and landing, as there is likely plenty of space to have a regular runway. I mentioned europe, as I know its situation well and in the video, the company was mentioning europe as a next expansion phase after the US. I won't be investing...

[@Croz89]

@@SwissPGO Runways do take up quite a bit of space, and have at least some cost to maintain. Being able to take off and land in a car park would be a lot more versatile.

[@asmolej]

Think about it more like that. The evtols will connect places that are not yet connected with e.g. high speed railways. Especially Switzerland made a lot of tunnels to ensure a good connection between urban areas. So the wvtols could be a possibility to connect two urban areas that are separated due to a mountain and where no tunnel exists so far.

[@rickwiggins283]

Because an investor puts their money into what he/she wants to invest in and not what others say they should. If/when point-to-point VTOL is perfected and cuts out all those interim segments you mention there will be large profits. An investor or rider may also decide for themself to not care about energy efficiency as long as the convenience outweighs the price.

[@Ichibuns]

In case the motors get stuck in the forward position, it would ALWAYS need to be within range of an airport. Yet another issue to be solved. I for one would love this. It would force cities to keep their airports open.

[@DumbledoreMcCracken]

I just want an electric self-launching sailplane, with the motor in the front.

[@DumbledoreMcCracken]

You also have to cool the motors (something rarely mentioned). The resistance in the motors goes up with heat, and to overcome that resistance you must: 1) cool the motors (which takes energy itself), 2) increase the voltage to keep the power output up, 3) or overdesign the motors (adding weight) so that the power lost due to resistive heating doesn't kill the power (resistance X current *squared* ).

[@someonespotatohmm9513]

They are underneath a spining prop, i don't imagine its to difficult, doing it without impacting prop performance to much is probaply a different matter. But combustion engines have the same issue but worse.

[@DumbledoreMcCracken]

@@someonespotatohmm9513 I don't think combustion engines are worse. Do you have an equation to show that? Are you an engineer?

[@someonespotatohmm9513]

@@DumbledoreMcCracken Just efficienty calculations, electric ~90% and ICE at best 35%. All losses are converted to heat (not 100% true but close enough for electric). I am not sure about chemical inefficienties for ice engines with NOx and CO production but it is not enough to cover the 55% extra heat generation. Edit: I forgot that the gas that is extracted from the ICe engine is hot... Still don't think its enough to cover the efficienty difference, but just an educated gues. Thinking about it the bigger problem is that the electric motors can't get to hot because the magnets demagnitize above ~80 C* (depending on my memory and magnets used, if any)

[@DumbledoreMcCracken]

@@someonespotatohmm9513 yeah, but where does the electricity come from when you park your car at night for recharging? Do you have a personal Solar Farm and a Tesla Power Wall, or a giant array of capacitors? Powerplants/the grid are roughly as efficient as an ICE. I didn't take into account the demagnetization of the magnets. Good point. I was thinking electromagnets only.

[@someonespotatohmm9513]

@@DumbledoreMcCracken Yea powerplants are more efficient becuase scale but I would say it isn't unfair that is lost in transport. This is not true when concidering CO2 because hydro, nuclear and even gas! But the plane already has the electricity so for heating it doesn't matter. About the magnets: The "best performing" electro motors use permament magnets, but depending on the aplication it might not realy matter, if so and they go with motors without magnets the temperature matters less.

[@brucebolla4148]

Really well done. The eventual use of electric airplanes will find its sweet spot, but until batteries become better. I believe it is limited for now. Let's not pooh-pooh them for going forward. It is an admirable endeavor and exciting possibility for the future. Thanks to Paul for all his research and humor. I always enjoy watching his videos.

[@Drinksfromtap]

I think you’re the first person I’ve seen write “pooh pooh” correctly in years!

[@TheRealCFF]

I think your comment about the “batteries becoming better” is the biggest problem. We’re about at the chemical limits of that with lithium ion batteries as they are. It’s not likely we’re going to develop better batteries anytime soon, if ever.

[@DemstarAus]

The challenge really is power storage. It's hard for us to beat chemistry on the energy density of liquid fuels. Refuelling time was mentioned in the video, but we don't have the ability to recharge these batteries that fast, and most of the electricity used to charge them comes from fossil fuels anyway. And the weight issue which is a difficult thing to overcome. I don't want to dismiss progress because it seems hard, but it's becoming the philosopher's stone of EV tech. Whoever "solves" battery improvement is going to be a bit of a celebrity.

[@jebise1126]

@@TheRealCFF well it seems they only need a bit more energy density in this case what is much bigger problem is how many cycles will last especially fast charge discharge. if they last like 500 cycles now and this plane will do 10 flights per day and if we assume that will mostly discharge battery that battery will need to be replaced in 50 days. really not ideal...

[@buildmotosykletist1987]

I presume you are referring to Lithium battery cells? I doubt they will ever work with aircraft larger than drones. Lithium does not scale well. Even EV size Lithium batteries don't scale. Yes, Tesla is doomed. What does scale is Hydrogen/Electric fuel cells. They don't work for your phone or for a drone but at small car to trucks size they scale exceptionally well. Because of the huge weight reduction when compared to lithium they may (or may not, i do not know) scale well for aviation.

[@pilotdane1]

I know no one will ever read this - I have been following you for years & years. I appreciate your work. Lots of these "in the works" - Like with Dr. Paul Moller (SKY CAR) - since '80's ("ish") are not going to be practical - Which is why I became a Pilot - until battery technology grows by leaps & bounds - it simply is not going to work. Always watch, but don't always reply / comment. Keep up the GREAT work....

[@joetroyner]

As a teenager I was so excited for the Skycar. I remember trying to get my parents to invest..

[@pilotdane1]

@@joetroyner I was a bit older but thought that was so cool. Still have a framed pic of it in my garage lol. Technology "flew" right past him....

[@foxabilo]

Excellent review of the facts. I'd love to see this happen but realistically it's not going to be before 2050.

[@rykehuss3435]

And funnily enough, we wont even have commercial fusion power before that. And I just doubt we would have Joby like service by 2050. There just wont be enough pilots, and AI wont be good enough to solo fly airplanes by that date. And even if we did, its still just shitty. Trains do the same thing, and way better and more efficiently.

[@goodboid]

Did you just pull that estimate out if thin air? Or is it based on some secret data/analysis that only you are privy to?

[@foxabilo]

@@goodboid Just a knowledge of life and past events and how long things actually take compared to the advertising execs projections.

[@dsauce8780]

I was thinking about that earlier! The sphere of things that are possible is much larger than the sphere of things that are impossible. More you learn about nature the more apparent this becomes. Always good content on AVWeb.

[@Design_no]

Unless and until there is a revolution in battery technology the ice is here to stay. Flying an electric trainer for an hour with no reserve is not a viable option.

[@mytech6779]

As there hasn't been a revolution in electric cell chemistry in 150years and chemistry theory now being pretty refined (Thus better able to predict maximum potential combinations.) I don't see any sudden revolutions, it is inherently a slow and steady field with no low hanging fruit.

[@PRGanapathy]

Time spent watching your videos is always useful and enlightening!

[@jcburleigh]

Thanks for this excellent presentation. As a longtime software architect/engineer, I've learned to apply various logical reasonings (that don't always seem obvious to me, at least) to seemingly cool ideas (that, not coincidentally, seem like fun projects). One of my favorite reasonings, or "razors" I suppose, I call the "but-if": When proposing a huge leap in tech (X) to solve a problem (P), and that leap requires numerous innovations (V1, V2, ...) that are of questionable achievability, ask yourself "But if we could do any combination of (V1, V2, ...), how might that impact our ability to incrementally mitigate (P), such that (X) would become less necessary?". In some sense, "but-if" is the opposite of another of my favorites, "synergy", which has often inspired me to do supposedly "impossible" things with great payoffs (in my little world, anyway), but also caused me to pursue dead-ends at substantial expense. Here, (X) is EVTOL, (P) is a combination of excessive traffic on limited networks of drivable roads, and you've hit on the innovations necessary. One (Vn) in particular is autonomy (pilotless craft): if "we" can achieve that, with the necessary combination of on-craft tech, autonomous monitoring, ATC changes, and so on, how could similar innovations be made in our automobiles and on our roads, such that traffic problems, especially accidents, might be greatly reduced? Another (Vn) is improved battery performance, which would likely translate well into automobiles, making them much more efficient and capable of long-range trips without requiring such long recharge times. At some point, if one doesn't assume that only the EVTOL industry will be "permitted" to enjoy the innovations it drives (and why would it, considering how widespread the industries have been that benefited from innovations driven by space flight, such as Apollo), it's worth considering that the proposal of a 30-minute EVTOL flight, in lieu of a 60-minute drive, might in fact end up being in lieu of, say, a 40-minute drive. Would saving 10 minutes be worth the additional cost and risk, when many of us are debating whether saving 30 minutes (on the same trip) would be worth it? Many of us love the so-called "Hail Mary pass" (I know I do). Like the Grand Slam in baseball, it's typically cherished as a last-gasp attempt to overcome what seems to be certain defeat with very little time left. But the best teams do not typically rely on "Hail Mary's" (or Grand Slams) throughout their games, instead focusing primarily on making incremental improvements. And the Apollo missions were most definitely more in the "Hail Mary" category, seemingly necessary due to the Cold War, in which demonstrating superiority in technology (as well as in basketball, figure skating, and ballet, among others) somehow became of paramount importance. The "but-if" rule has also significantly mellowed my fascination with space flight and Interstellar-style colonization of space (being, in contrast to Star Trek, driven by seeming necessity): if mankind could truly achieve all the (Vn) necessary to achieve the (X) of usefully colonizing a distant planet for millenia of occupation, in order to escape the (P) of a dying Earth, why couldn't it apply some combination of (Vn) to "fix" Earth to extend our ability to live here? The "Hail-Mary" logic, of escaping hordes of "problematic" humans (without just wiping them out here), is (to me) one of the best arguments in favor of (X) here, assuming it was truly necessary (and it likely wouldn't be, considering how much of (Vn) would have to include advanced psychological and medical care to flourish in space and on a distant planet); otherwise, it's hard to believe we, or really any species, could master interstellar travel and yet not figure out how to address resource and other issues on their planet (by, say, mining nearby asteroids, if not their own planet's interior, among other things).

[@vahtikoira2125]

Great video. I've worked in commercial aviation maintenance for over 30 years now so I can only imagine that the high cycles and short turn time usage Joby envisions is going to wear out these ultra-lightweight composite aircraft and their electrical/electronic components in a predictably short duration in ways they have not yet imagined. The first few that break up in flight or careen into a building are going to run up against the ever present smart phone video cameras of the urban environment to give the public a close up view of the carnage.

[@jebise1126]

well... ideally they should have very soft landings so... what could possibly go wrong?

[@LIamaLlama554]

Ah yes, and legacy a/c never crash, right?

[@KeithJohns]

His dry delivery is great. "If the entirety of civilization thought this way, we'd still be driving across the country looking up the assholes of horses." Hilarious!

[@Fleetwing1627]

Great video, Paul. If only more American media outlets presented factual, unbiased reporting at such a high quality level. I think the biggest thing going against Joby and others like it will be the FAA and the expectations of airline safety levels. They're going to have to certify stability algorithms that can handle engine out scenarios and other failure modes, as well as handle all the electrification certification challenges. But then there's the airspace regulations--how long will it take to do what needs to be done to handle flying taxis of any serious volume?

[@JR-bj3uf]

I ask a very experienced pilot once why the dreams of the 1950s flying cars were never realized. He just said "traffic." Can you imagine the kind of traffic nightmare that wold occur if there were as many planes as cars?

[@PerfectInterview]

What people don’t realize about batteries and energy density is that a battery, any battery, consists of an anode, a cathode, the electrolyte, an insulating layer, and a case. Energy is only stored in the electrolyte, the rest of the components are needed to make the battery work but they don’t store any energy. 20 liters of avgas requires a container of some sort but the rest of the volume is pure chemical energy. So batteries are never going to approach the energy density levels of hydrocarbon fuels.

[@sleeplezznightz]

If the FAA existed in 1903, airplanes would have never existed. Just a thought.

[@ammerudgrenda]

Good one 😆

[@ZeeCaptainRon]

I'm surprised that the comparison of aviation fuel energy to battery energy was not discussed in this video. The energy density of the best Li-on batteries today is around 250wh/kg while JP/diesel is 12KW/kg 48 times better energy density and very fast fueling. Of course, batteries are getting better, but will they ever get that good.

[@jimmbbo]

Paul, kudos for your thoughtful and detailed presentation... I think the concept has merit and admire the engineering and creativity, but IMO the power technology is perhaps as much as an order of magnitude short of commercial success. Additionally, in operations the challenges I wonder about are 1) the logistics and infrastructure to support a robust air taxi operation in the various city locations. 2) the viability of e-VTOLs in IMC conditions - "fuel" for diversions to alternate airports f'rinstance? A "hybrid" air and ground transport system ala the 1930s cross country trips? 3) the turnaround time - the current lithium battery charging cycle is far too long, meaning swapping out a 2000lb battery instead of charging? Assuming a 2 hour round trip block time and flying 7 hours a day, how many batteries would be required to support each aircraft, plus spares? It's a capital expenditure, but represents significant chunk of change, given the lifespan of the batteries.

[@n86121]

1. Maintenance question: Not to mock faa too much, but will FAA vacate requirements for an FAA certified A&P to do an annual? 100 hour inspection? Or will FAA say, “oh, we were just kidding about all those silly requirements…” 2. Market question: What percentage of the overall general population feels “safe” in small aircraft? In even light turbulence? Orr even light turbulence in a 757? Some years back demand for turbine aircraft softened in part because passengers felt much safer in small regional jets than “those small prop planes.” 3. Market observation: Is it Rio de Janeiro where they have helipads on most office buildings and use R22s like taxis? I recall someone mentioning to me that traffic was so bad it took 2-3 hrs to cross the city anytime of day or night, so an across town meeting was literally a day of travel Pre Covid). Looking at that as an evolved market study case of point-to-point urban air travel, how many flights per day (at R22 hourly rates) happen as a percentage of total population?

[@chrishb7074]

Even leaving the fundamentals of energy density aside for now, one thing the pandemic has demonstrated is that telepresence technologies make the actual transportation of (at least) a hundred and something pounds of flesh and blood, somewhat unnecessary. The demand for people to actually be there in person for many kinds of business activity is much less than it was two years ago. We need to question the assumptions about the market for business travel in particular. For things like air ambulances in congested cities there could be a real benefit, but then it only has to be cheaper than a fully kitted EC135. How are Harbour Air getting along with electrifying their Beavers?

[@dragthatsht]

If there's one thing you can count on, managers like to get in the way. They will start requiring people to return to the office. They can't justify their existence without it. People have short memories, and can justify anything if they want it bad enough. And there is nothing most people want more than power.

[@kevinheard8364]

.... a very good point .... just wish I had been smart enough to think of it

[@davidwhite2011]

I can only think of Bender from Futurama, "Meat bags".

[@singleproppilot]

I work as an aircraft mechanic for a part 121 operator, which is a job that I’m sure most people in these comment threads can understand the importance of. I always joke that I’ll try working from home when they figure out how to land a 747 on my street. I come from a family of blue collar workers and I always wonder what jobs people do from home, and how secure they feel in those jobs knowing that their company can hire someone from anywhere to do them.

[@chrishb7074]

Update: ‘The Economist’ UK newspaper, today quotes normal commuter travel (car, train, bus) is down 25% compared to December 2019, based on mobile phone location data.

[@frank_av8tor]

Not mentioned but a huge factor, including for certification purposes is how a battery fire is going to be managed. Lithium battery fires are nasty things, ask Boeing or Samsung. As a freighter pilot we carry these types of batteries perfectly stored and packaged all the time, most of these shipments are CAO (cargo aircraft only) hazardous materials no passenger airline can transport. Should a lithium battery fire occur, we're instructed to consider landing immediately, not as soon as possible, not at the nearest suitable airport. Immediately! Read about UPS flight 6 accident. It's that scary.

[@asmolej]

Well, these EVTOLs will fly at very low altitudes and their vertical landing ability allows for a very quick landing in a small place that is free of obstacles. I could imagine that an emergency landing would take about a minute.

[@mrhelichopper]

Simply the best, most rational, objective and fact based summary I have seen. Fantastic video, thank you and well done.

[@EdJZatta]

Paul, Happy New Year. Keep the content coming for 2022. Best aviation presenter period! Cheers.

[@rigilchrist]

This is really educational Paul - thanks for shining your clear light on this whole business. No-one does it like you do.

[@Not.a.bird.Person]

I've always been a bit skeptical about the claims of E-VTOL companies. Not a lot of people are rich enough to afford a 100-500$ taxi with limited accessibility to urban, rural and suburban areas. Lots of people may say they would like to do so but few are actually capable of supporting financially this endeavour, let alone be bothered to go to a terminal and actually use the system instead of their car. There's also lots of red tape to consider when trying to build massive infrastructure projects like hundreds or even dozens of E-VTOL airports. I tend to agree on the practicality of distributed electric engines however, they have a lot of benefits that I think are valuable to the industry, mostly the low maintenance requirements and reliability. They probably will find a niche.

[@chicoarraes]

If EV aircraft are gonna work at all, they will need to move to a system of battery replacement instead of charging. Charging would be done slowly at the hangar while the aircraft simply changes batteries between flights, because there is no way charging would be accomplished as fast as fueling up with gas. Not to mention the toll it takes on battery life, as you explained very well.

[@n86121]

To paraphrase my favorite physics T shirt from the 1980s, “Force=mass x acceleration, It’s not just a good idea, it’s the law.” Also realize investment managers that are supposed to be investing in “new” things don’t want to be left out. “We need to get into this drone thing” Even if it is an insignificant micro percentage of portfolio, written off the moment the check clears, they can say to the people giving THEM money, “We have made a 100m investment in the future.” And keep getting more money to invest. Around it goes.

[@BEAMChannel]

What I worry about is how this will interact with ATC, most the cities they plan on serving are under class-B airspace

[@DrewLSsix]

There's nothing to worry about, as has happened countless times before the emerging industry will have to work towards making their case to the authorities and the authorities will have to figure out what rules to put in place. They aren't simply going to spring up and start doing business overnight.

[@BEAMChannel]

@@DrewLSsix i have seen way too many startups that seem to think that rules are things to be ignored when they get in the way. I mean it would be pretty cool if they pull it off but I am skeptical

[@magusd123]

Pilot here. For all multi engine rotor style aircraft, I always one question. How many engines can it loose

[@PghGameFix]

As always great vid. I've flown RC planes since the 70's, and electric was, at one time, something only the hard core wanted to do. you would take a typical "40" sized model that would have been 6lbs with a glow engine, and then swap it out for an under powered electric system with NiMH cells, and it now flew at 12lbs, for half the time, with poor performance. But now at my flying club, it's hard to find a glow model flying. LiPo batteries and brushless motors have changed things. But the charge issue is still real. I could take 2 min to refuel a glow model, and fly again... but takes at least a hour to charge the electric. (LiPo doesn't really like to be charged more than 1c) But there is no magic with electricity. To charge that monster pack in an hour would require power wires as thick as my arm to carry enough current, since they can't have high voltage. (most likely) And how is this going to effect the power grids that are already a problem? So, I'm like you... I think there will be a roll at some level, but not where Joby thinks it will be. On the side of the batteries... from personal use... We know the truth about LiPo's. They won't hold up, and they will degrade. I've talked to a couple Tesla techs, and I've been told that the batteries that are supposed to last 8 years DON'T !! They are known to swap sections of the pack when cars come in for service, and they don't tell the owners because they are under warranty. I'm happy to see this new section of flight... but I don't think we are there yet.

[@someonespotatohmm9513]

The Li-ion cells are more stable then lipo. So slower charging and discharging but also a longer life.

[@jebise1126]

800 volts i believe... thats the voltage in electric cars. but yeah if you want to fly around few hours per day degradation quickly becomes an issue.

[@nomadpi1]

This video should be required viewing by each high-school science class. This can be sufficient to rebut the current view of environmental impact on conversion away from internal combustion engines.

[@tomc.5704]

19:35 - oof, that chart is damming. $90 to cut a one hour trip down to 30 minutes? Even if their aircraft is extremely safe and works exactly as promised (and every day is a beautiful VFR day), that's a hard sell. It's hard to see where Joby's eVTOL air taxi service from station to station manages to beat old fashioned public transit -- aside from luxury markets who can afford $180/day for a round trip ticket. Then again, I don't really know how much public transit costs, but a quick google search suggests that if you want to build a new subway tunnel, it will cost in excess of $350 million per mile --- but subway tickets are still a hell of a lot cheaper than personal air taxi tickets, and trains are still far more fuel efficient per kg/mile than air transport.

[@dbmn7571]

In addition, many business related trips that used to made in order to meet in person are no longer made in person. Covid changed that forever. There must be compelling reasons to meet in person today vs joining a remote meeting. Take away the government money, including the military, and the air-taxi business model is toast. Same with ev cars, trucks, windfarms et. all; no government money (actual taxpayers money) and there's no business. Uber is just another taxi service that uses an app and skirted local regulations for taxis, but it's still just a ride from point a to point b and now the taxi ride and uber ride cost the same. Can't ever see using an air-taxi service as proposed by Joby or any similar company.

[@johningram1920]

I am a carpenter, I make on average $200.00 per hour, and I would gladly pay $180.00 to avoid ATL traffic. if It is tax-deductible then great.

[@tomc.5704]

​@@johningram1920 Yeah, most people don't make $200/hr lol. You _are_ the luxury market. Obviously if sitting in traffic for an hour costs you $200 you'd pay $180 to avoid that Looked up some income tables and probably the top 2-4% are viable. So you are right, there is a market. Now they just need to make it safe, get it certified, and not have the cost double when reality hits. And have the market they hope for materialize. And in Atlanta, accept that they'll be unable to fly 30% of summer evenings due to thunderstorms. As Paul said -- they think they have everything figured out, and they're ready to show us. So show us. I'll be excited if it really happens.

[@moonasha]

when I clicked this video, never did i think I would hear paul say "looking up the assholes of horses" 😂

[@clarencegreen3071]

Juvenile humor, in my opinion, that detracts from the presentation.

[@CompleteWalkaround]

Thanks Paul, Great stuff

[@guard13007]

Took me forever to finish watching this, but thank you for the in-depth coverage on it.

[@ELMS]

An excellent summary. Thanks Paul.

[@therestorationshop]

I'm not sure about the "flight share" business model either but for regional air travel I think this makes perfect sense.

[@AnthonyHigham6414001080]

If distributed power, electric thrust, fly-by-wire does actually have a future why don't these companies go for a hybrid power supply whilst waiting for battery technology to catch up? A small gas turbine/electric generator could plug the gap allowing certification of the rest of the systems. The answer is probably they don't believe their own hype and are just milking investors.

[@mckenziekeith7434]

Because it will make it even heavier and because a lot of the true believers are totally opposed to ICE's. You may say that if you have a generator you can use smaller batteries but this is kind of true and kind of not true. Batteries have two limits, one is their energy density (capacity) and one is their power density (how fast can it discharge relative to its capacity). If the battery gets too small you will run into the power density limit. Another way to say it is that you can't drain a battery in 5 minutes. So maybe you can cut the battery size in half and add an engine and be OK. But you can't reduce the battery capacity down too much.

[@leoh2502]

This is why I like EHang EH216 - It's by far the simplest passenger grade eVTOL design out there.

[@johngilbert1325]

It's been said in aviation, you can go out and try a new powerplant. Or you can go out and try a new airframe. Both are already fraught with expensive and consequential risk. But you can't do both. These EVTOL companies are trying to add a third component- a new fuel source - and do all three. Ummm... We've all seen aviation companies come and go trying to revolutionize one, but now all three at the same time? We got one of these EVTOL startups at my local regional airport- $1B+ in investor money - and they're going for it with a different target market- you can see how they're spending the cash - big BIG fleet of fixed and rotorcraft for everyone in the company to fly - a very Silcon valley approach. The deck is stacked well against them for sure.

[@nunyabidness3075]

Are you telling us that the eVTOL company at your airport used their investors’ cash to buy certified aircraft the employees can use?

[@mytech6779]

Yeah on the flip side I see "look how efficient this new e-plane is" while people totally ignore that the improvements are 100% airframe/aerodynamics and so could be applied equally to a piston powerplant.

[@someonespotatohmm9513]

@@mytech6779 No it is stupidly more efficient to convert electrical to mechanical power. The new powerplant rule also aplies less here then for traditional engines. Electrical motors are a lot less complex and lessons learned from, for example, automotive engines transfer a lot better, because the design is less tailored to being an aircraft engine, compared to combustion engines.

[@jebise1126]

well but they would not sell these to individuals but to build them for them self so that doesnt really apply for this case

[@mytech6779]

@@someonespotatohmm9513 Your perspective is absurdly oversimplified. By the exact same logic of only looking at one sub-component, I could equally say that energy loss in a liquid fuel system is stupidly more efficient than the energy losses in an electrical power source.

[@rre9121]

It's not something I'll invest in, but I'm perfectly happy to see how it goes.

[@MC-yb5le]

Intel did, 59 million shares in Joby.

[@wpfilms2]

Thank you Paul, that is a very balance and fair video on the subject. Before the flames come, I will preface this commentary that I work in this space and have a strong bias for electrification (and hybrid) in aviation. As far as the USA (FAA), I have often stated that Beta Technologies is much overlooked and have done amazing work, practical approach, more comprehensive with an entire eco system from charging to sensible markets to start, as well as some really good reporting from Eric Adams. I hope AV Web will explore more into their programme and more of the naysayers actually have a look before forming opinions. Geographical perspective is very important too. China (like EVs) is much overlooked and frankly running away with the AAM or eVTOL much like they have with EVs in automotive (and to some degree more broadly with electric aviation). Ehang has completed 20,000 autonomous flights, many manned, in several countries. Now Xpeng and Autoflight have full scale prototypes up and running. Also, China funded Pipistrel 5 years ago with €390m funding. The CAA have plans for certification and well as a well defined roadmap for these type vehicles as early as 2022 which will put China as least 2 years ahead of Europe and 3 years ahead of the USA (which is a shame considering the historical spirit of innovation in aviation in the US) That is a big advantage with the enabling technologies to make electric flight work. The FAA needs to pull their fingers out if they want the US to be competitive in this space. eVTOLS are just a segment (though some 200 plus ongoing projects) of electric and electric/hybrid aviation. There are projects ranging from eparamotors, gyroplanes, ultralights, bushplanes (eSTOL Zenith with a solar canopy in the UK) to small commuters that make up electric aviation. Regionally mobility, or commuter space, is also overlooked with companies like Eviation, Heart Aeropace, Tecnan, ZeroAvia, Pyka, Harbour Air, all working on this… There are 2B airline tickets sold for 250nm and under trips - not a very good use of a 737 to just go up and down when it was built for longer distances. Electric propulsion can address this market with lower operating costs. Electron Aviation in the UK have a proof of concept flying prototype at 7.5 kWh per hour. That is pretty efficient. Think of the possible addressable market on the African continent and Latin American market where road access is difficult and the automotive EV (Teslas of the world) have largely ignored. And finally, there has to be more nuance in the discussion around electric flight with separating out electric propulsion from energy storage - they are two separate technologies. Electric motors have made some amazing progress lately, especially around axial flux architectures. Just have a look at Rolls Royce Spirit of Innovation flying at 350mph on batteries. Thanks to automotive, battery technologies are getting funding and making progress on more traditional chemistries like Lithium Iron Phosphate to emerging chemistries like Li-Suflur, Li-Metal, and solid state all starting to make it out of labs and into commercial production. In the past, there was very little financial incentive, now there is… Hydrogen, micro gas turbine generators, and synthetic fuels are also making progress. You have to keep in mind, the Pipistrel electric trainer has old battery cells due to the EASA certification process. EASA and FAA would do everyone a favour by getting experts in these industries and run parallel R&D so they are not always playing catch up. Again, putting into geographical context, China is leading the way on battery tech & production. In automotive, China accounts for 60% of EVs made and sold, have several cars now 1000km range and they will be the largest market for electric aviation. GA has to get out of the 1960s and start taking a page from automotive. If we had GA tech in a car, very few people would be driving - imagine paying $30,000 for a 125bhp engine, having to manage fuel mixtures and rpms whilst driving your car. The reliability of an electric powerplant will go a long way to improving GA safety.

[@earlystrings1]

No one wants a Lord Kelvin award but it’s hard to think of a transportation sector less favorable for an EV revolution than commercial aviation.

[@flyingcarguy]

The motors are great it’s the batteries I have an issue with…with cars and planes…

[@JAMESWUERTELE]

Batteries won’t change. That’s why the were trying reactors in the past. They were smart back then.

[@jebise1126]

@@JAMESWUERTELE cool statement... lord kelvin style one

[@avshiloh2438]

You can’t help but love Joe Bertorelli.

[@javidol1544]

Sure man, you love the guy but can't even be bothered to learn his name.

[@onemoremisfit]

Might be useful even if not revolutionary, but calling it "green" and implying it will help "save" us from otherwise inevitable self destruction is where I draw the line.

[@davidbrayshaw3529]

The market place loves to hear that we can consume our way out of a problem. It's an added bonus if you can park your shiny "solution" in your driveway or hanger for the neighbours to see.

[@onemoremisfit]

@@davidbrayshaw3529 Trouble today is when the market doesn't embrace the "solution" then we get govt coercion forcing it on us. And it aint solving anything aside from making a few more billionaires richer.

[@davidbrayshaw3529]

@@onemoremisfit Exactly.

[@ttystikkrocks1042]

After listening to this very clear eyed assessment, it dawned on me that Joby's game is all about being the technology that can implement new innovations fastest; they know that batteries are the problem but if they're already building aircraft then they'll be in the right position to get the upgrades to market first. This is the only way their whole scenario make any sense at all, fiscally or otherwise.

[@AgentSmith911]

Electric motors are amazingly efficient; about 85 to 90% compared to ICE that are usually under 30% efficient. They are lightweight as well, and have lots of torque and can rev high. Perfect for airplanes. Jet engines are more efficient than ICE, but as you pointed out in this video, the main problem for electric airplanes is obviously the batteries. While avgas has an energy density of about 10 kWh per kg, batteries are usually between 150 to 300 Wh per kg. We need a battery revolution.

[@mytech6779]

the motor is 90% but the battery discharge is 80-90% and charge(at the battery not including distribution losses) is 80-90%, then the inverters and other circuitry probably takes another 10%. So you are down to 55-60% which is not much better than a good diesel cycle engine. Now consider payload is cut in half due to power wasted hauling the battery mass and you are now under 30% total system efficiency, on a per unit of payload basis.

[@AgentSmith911]

@@mytech6779 Most trucking diesel engines are under 30% efficient, and then they have engine to wheel energy loss as well. One exception is large marine 2 stroke diesel engines that can be much more efficient. But I doubt large ships will be replaced with batteries any time soon, maybe as a hybrid solution with hydrogen or nuclear propulsion. For short haul trucks, EV can be done and then hydrogen can be used for the largest trucks and long haul.

[@mytech6779]

@@AgentSmith911 Power losses after the motor are equal for all power sources so irrelevant to the comparison of power plant efficiency. I am not talking about trucks or crosshead ships engines. Though an aircraft is much closer to a ship than a truck in desired power characteristics, which is why turbo-shafts are found in both ships and aircraft but not trucks.(Slow steady power changes, predictable constant load.) In any case a large crosshead in a ship is 45-50% ish and a commercial truck engine (not some hillbilly "tuned" pickup) is 35-40%; higher efficiency without emissions regulations, lower with emissions regs. Even Otto cycle engines can get 25-30%, maybe your sub 30% number is data for very old engines or includes stop and go or light load operations. But none of these variables are factors in aviation power.

[@mytech6779]

@@AgentSmith911 Hydrogen from what? ...cracking natural gas is the only economical source until the elves capture some more unicorns to help build a practical fusion plant. And since the raw NG is far easier to handle and has higher power per volume than H2, why not just use NG?

[@AgentSmith911]

@@mytech6779 It's not an equal powerloss if an engine has to go through gearing and a long driveshaft before getting to the wheels, and electric motors often doesn't need an external gearcase or shaft and can in some cases be mounted directly at the wheels or in the wheels of the vehicle to minimize losses. The Rimac Nevara is an example of that. When it comes to airplanes, an electric motor has the advantage of being lightweight and providing high RPMs and torque numbers without causing much vibration or noise.

[@paulj.ingram2839]

Joby’s research plant is in Marina, CA. That’s close to Carmel Valley, CA, where we bring Santa in on a helicopter. In 2019 someone from Joby gave me his business card and suggested their craft to fly Santa in. They never followed up. I was wondering about their progress. Now I have my answer.

[@mctransportation9831]

The 1st step in economically viable electric flight is 2 hours endurance in a trainer. Just my 2 cents.

[@mytech6779]

Yeah if you can't get 2 hours with literally zero payload and a minimum crew how can anybody be suckered into thinking there could be economic payload?

[@therealrobinc]

Excellent video. Another DOOMED project that hopped onto the doomed eVTOL bandwagon. 1. WEIGHT. Batteries are HEAVY. And they remain heavy when depleted. 2. POWER. Their energy density is LOW compared to AVgas or Jet A. 3. TIME. They take TOO LONG to charge for speedy turnarounds unless it involves battery swaps which in & of itself is costly. 4. LIFT. The amount of lift they provide is CONSTRAINED by the weight of the batteries. More batteries will not generate extra lift to carry extra payload. They can only provide slightly more than to lift it. 5. SAFETY. You can cut off fuel in response to an engine fire. How do you put out a battery fire mid flight? You CANNOT. 6. ENVIRONMENT. The mining of rare minerals for lithium batteries is POLLUTING. As is the management & processing of battery waste. 7. FIXING WHAT'S NOT BROKEN. What problem(s) does eVTOL solve that isn't already solved by helicopters, especially since most electricity is still currently generated from fossil fuels? Battery storage results in a percentage loss of energy. And battery production results in environmental pollution from the mining of rare earth metals. Linking CO2 emissions to climate change is based on bad science to support an insidious globalist elite depopulation agenda. Good science that links global warming to sun activity (which we cannot control) is conveniently ignored. And even if the entire earth were to stop using fossil fuels, the impact of CO2 emissions is negligible against nature's forest fires, volcanic eruptions, etc. Instead of being a villain, CO2 is the gas of Life that supports plant photosynthesis to create oxygen in the presence of light, a fact from primary/elementary/grade school science that many choose to forget. Here's an excellent article on eVTOLs: www.flyingmag.com/evtol-opinion-fuller/

[@nunyabidness3075]

The existing aircraft owner population isn’t just skeptical, they are motivated by freedom, money, and status. They perceive a decline in all three if the new technology works out. More restrictions on their flying their planes. Their planes could lose value or be grounded, and their status could suffer as well unless they adopt the new tech (for most of us in our old age). This would all be unimportant except that history shows that the grumbling does seem to have an adverse affect on advancements and adoption. Combine that with FAA intransigence on anything, and Joby and friends need to overcome a lot more than just physics.

[@joesterling4299]

I don't think they're afraid of losing what they have. The fear is having something that is nowhere near ready for prime time pushed into the scene because of politics. Electric aviation is a noble goal. That doesn't mean it's going to work well enough anytime soon. I applaud the first 30 seconds of this video. (The rest is pretty good too.)

[@nunyabidness3075]

@@joesterling4299 I just cannot see that causing the level of derision you see on Avweb and other places. Not that everyone is being rational, but the majority of posts claim the companies are ALL scams (sometimes reasonable based on the story from a group with nothing but drawings but even from companies with flying aircraft). If nothing gets off the ground, it’s not really in the scene is it? I’ve yet to see a single post (which means they must be rare), complaining about the investment not going into aircraft projects that really could work.

[@lzoltan70]

I've laughed my ass off (I have been entertained with your righteously mildly-sarcastic style), while having been professionally informed ! Great video! Thanks, Paul ! Rocker

[@MenwithHill]

The technology itself didn't sound too bad but once you got to the business model I really lost faith. It sounds typical of silicon valley startups with crazy lofty ambitions, a lot of VC funding and not a lot of actual know-how to make their pissing of money make sense

[@HiddenWindshield]

The narration on this video was really low. I had to turn my volume up to be able to understand, it was hard to understand you over the keyboard sound effect at 0:47, then that cocking sound effect at 3:31 nearly blew my eardrums out.

[@scenicdepictionsofchicagolife]

I am excited for electric aviation not for the sustainability aspect, but for the simplicity and in flight reliability. This means safer and seemingly cheaper flying.

[@vahtikoira2125]

Did you miss the video's run-through the safety numbers of commercial aviation/airlines? I've worked in aviation maintenance for over 30 years now, the turn time usage environment Joby envisions is going to wear out these ultra-lightweight composite aircraft and their electrical/electronic components in a horrifically short duration.

[@petcatznz]

Cheaper flying, just like the cheap nuclear power generation we were all once promised. Time will tell though, I'm happy to be proved wrong on this.

[@someonespotatohmm9513]

@@vahtikoira2125 They are not competing in the comercial aviation market, but the airtaxi market. The reduced vibration and proven reliability of electeric motors should increase safety and/or reduce maintanance. The lightness of the unloaded aircraft is mostly becuase electric motors are very light compared to combustion engines. Just as a small scale example: you can get ~2 Kw of power out of 100g of electric motors for several seconds if the cooling is sufficient.

[@jebise1126]

@@petcatznz nuclear power is still cheap so no idea what are you talking about

[@jebise1126]

@@vahtikoira2125 yes... and he clearly stated that engine is often a problem. electric motors are far more reliable than internal combustion engines.

[@Maynardtkrebs]

Thank you for this in-depth presentation on ePlanes. Maybe they should think about diesel electric, as in locomotives?

[@nattinotti6934]

First off: thanks for the video! This buzzer is heavy (always carries 1300+ lbs of batteries), funny (with 20 min reserve?), unsafe (what happens when bird strikes, equipment malfunction, pilot errors?). This thing can't glide and probably won't have parachute either. Another buzzing electric coffin. This is a dead end for another reason: because pure renewable energy is a fantasy: it can't be sustained long term because of the same argument: any "green energy" source regardless of its type offers very low power which is [energy density] x [speed of energy transfer] in this case the speed of ion transfers in electrolytes]) these machines will always require bulky, heavy and cumbersome designs for electrodes areas to extract that power into the propulsion. It is physics and no amount of imagination or speculation will change that. Another argument is (follows from green energy sustainability fantasy): these inventions will compete and use fossil fuels to recharge their batteries. This won't work for the obvious reason: you have an additional inefficient energy consumer built into the current fossil fuel consumption chain. And why have that when you already have mid-range aircraft platforms, which are more economical and safe? Also since these drones will consume fossil fuels you need to account fuel production cost into the efficiency of those drone designs and they won't be able to even come close to the current efficiency of the turbine and ice engines. The modern two cycle gas generators are 64% efficient. This is what you should know when you think this aircraft is 90% efficient - it is not! It is less than 64% efficient already. Make current airplanes better, make cheaper glass panels, make cheaper and efficient engines for GA is much feasible route than wasting billions of investors money on these jokes.

[@lancomedic]

I think the eventual problem of this is not that it can't be done, but by the time it is done there will not be a market for it. I think that the past two years has shown us that meetings in the future will take some sort of virtual form, maybe 3 dimensional virtual reality by that time. Also as the economy becomes more global, short urban hops won't be necessary. What will still be needed is transport to larger transportation hubs that will still provide the long distance transport, whether it be in the air or over land. In urban areas I see this as some sort of land based autonomous system where occupants will be in their own personal compartment, be it an autonomous driving electric car or maybe an underground autonomous rail system with personal capsules instead of subway trains.

[@conantdog]

Jet fuel or diesel is a fabulous product 👌

[@chadx8269]

An energy density 10 times of a battery. A beautiful substance.

[@waynerussell6401]

@@chadx8269 Why waste it on combustion at 20% efficiency?

[@MarioVesco]

Great contribution to the debate on electric aviation and eVTOL. Very well grounded and argued as well as level-headed, open minded and all-in-all intellectually honest. Just the kind of approach that this skewed sector needs in order for competency to retake primacy over hype.

[@Zuckerpuppekopf]

They are probably betting there will be breakthroughs on battery energy density in the next 20 yrs to make eVTOLs practical...which they clearly are not right now.

[@cruiserflyer]

A major pivot point in the viability of this tech presented in the video is the idea that they're going to have to deliver all this performance with the restrictions of lithium ion batteries, but it is very likely that by the time this aircraft gets it's certification, better battery tech will be available because the auto industry is driving(pun intended) the economy of scale improvements in battery tech. Joby's technical position only stands to improve with time.