Doing some math. Regional jets get somewhere around 45.9 seat miles per gallon (1). So 30 seats, going 125 miles would take around 80 gallons of jet fuel. This is likely low because all the jets listed are bigger and likely flying longer flights that are more efficient but just go with it.
Jet fuel has a specific energy of 12 kwh/kg and a density of 6.7 lb/gal (2). So 80 gallons of jet fuel is 536 lb, or 243 kg, and contains 2,916 kwh of energy. Jet engines are not very efficient, so lets say only 30% of this energy actually ends up being used. So 875 kwh.
Lets say we are using batteries that are 300 wh/kg (0.3 kwh/kg), which seems on the high side of what electric cars are using now (and that there are no efficiency loses in the electric motors or elsewhere).
Now maybe I messed up my unit conversions but I think that means to carry the same energy onboard you would need 6,428 lbs of batteries. And you are still going to carry atleast 1,600 lbs of fuel on top of that. And you have the weight of both electric and conventional engines.
I could see this reducing costs like they say but when many big costs are fixed (pilot, hangar, etc.) will this actually make sense? Will airlines fly something that has thousands of pounds less payload than a competitor but lower running costs? I don't know but it will be interesting to see.
Energy density alone is a misleading metric, because what matters is how much energy actually gets delivered to the drive mechanism. It's actually not that hard to beat gasoline, because despite its excellent energy density, gasoline engines are only 30% efficient. First and foremost a gasoline engine is a machine for producing heat and noise, and only incidentally for producing forward motion.
I think lithium air batteries will be the real inflection point for aeronautics. Li-air has potential density 12 kWh/kg. CATL is focused on this tech. May be some years before they are able to achieve the full potential density. Still, as the other commenters said, the efficiency of electricity make make up that difference.
Also for traditional fuel you don’t have to carry half of the fuel - oxidizer comes from air. And then when you spend fuel, you have less weight to carry (which becomes noticeable on the plane).
If they can get the range to within what, for example, an Alaska Airlines/Horizon Q400 flies from Seattle for regional flights (with reserve for diversion airport), that may be sufficient for some purposes.
In terms of operating cost, not just cost of fuel, but if the electric engines can be much less costly in terms of periodic maintenance and overhaul. Maintenance and overhaul costs on turboprop and small jet turbine engines are not cheap.
So if they are doing the hybrid approach and just using the conventional engines during cruise they will have way reduced maintenance costs on them. The need for max thrust during takeoff drives a ton off wear and tear, so removing that would be big. If they are able to do electric only that is even better.
As a rule of thumb, when you find yourself looking at an existing internal combustion vehicle and converting fossil fuel energies and efficiencies using battery gravimetric densities, you’re almost always at the “garbage in” stage of GIGO.
This plane isn’t a 737, it isn’t even a jet, it doesn’t run the motors the same way, the flight profiles are all different.
The economics to do what planes do today make no sense; but i think that's making the analysis the wrong way around.
There are opportunities for which airplanes have never made economic sense because they have big fixed costs like pilot, hangar, fuel-infra, engine(-maintenance). So will small short haul (?pilot-less) rechargeable planes have enough allure to beat out alternatives where planes were never considered before?
probably not at any major scale in a future where it competes with other autonomous transport, but that's me guessing at numbers. There will be enough of a market to build these things for niche constraints (eg the fuel-infra if small modular reactors become widespread).
The big problem with autonomous airplanes is they still require airports. I don't have a runway in my backyard, and I can't build one because someone else has a house there. My closest runway is about 20 minutes away, and then once I get to the far airport it is another 20 minutes to get where I'm going. This is why commute by airplane will always be a niche only a few people can do. In turn this means airplanes will never scale to be as cheap as cars are (a new Cesna stationair HD MSRP is over $700k - I submit that if they were building 40 per hour like many SUVs are built the cost would be around $70k)
Even a farmer is unlikely to be willing to give up that much space from their farmer operation. I do know farmers who have their own private runways, but they love flying and so are willing to give up some income to have a runway. They are giving up thousands of dollars in gross income to have that runway.
I happen to have a backyard that is big enough for a helicopter (I think - I never measured but I think I'm at the minimums the FAA requires), but I have an oversized yard. There are a lot more places for a helicopter. Most local parks have enough space, but I think communities would object to regular use. (if used only a couple times a month no problem, but more that and the noise and need to clear everyone else out will make it an objection)
My guess (I'm not an engineer) is landing weight limits are more then because the airplane will never have more than that anyway. They need a little better suspension in case of a hard landing, and different training for the aircraft (which you need anyway) to account for it handling differently, but otherwise it is still an airplane. Maybe bigger spoilers or some other part as well to better bleed off speed.
They need to account for it of course, but it seems more like account for it, not difficult. Any engineer in this space able to comment?
Landing weight limits are less than takeoff limits because of the extreme stress it puts on the landing gear. This is why planes that have an issue right after takeoff often need to dump tens of thousands of gallons of fuel before they can land.
>Aircraft have two main types of weight limits: the maximum takeoff weight is composed of dry operating weight (DOW) plus payload (passengers and cargo), collectively the zero fuel weight (ZFW), plus the trip fuel, contingency, alternate, final reserve and the block fuel (taxi fuel), and the maximum structural landing weight, with the maximum structural landing weight almost always being the lower of the two. This allows an aircraft on a normal, routine flight to take off at a higher weight, consume fuel en route, and arrive at a lower weight. [0]
They discuss quite a bit of this in the video. I actually thought it was a decent walk through of why they're targeting the space they're targeting, and how they're thinking about exactly these problems.
Some items to consider from the video
1. short flights spend an large amount of energy simply having the engines running during taxi to/from the runway.
2. Take-off also consumes much more fuel than cruising.
3. 1 & 2 combine to push airlines to prefer larger & larger planes making longer trips when using fuel (it's how they're managing that 45.9 seat mile number - it get much worse for shorter trips).
4. They're already pushing the 400kwh/kg range for batteries (I believe he makes an offhand comment in the video that they're using 8 packs, with roughly the capacity/weight of 4 tesla battery packs - which would put their batteries in the ~4k lb range if we estimate by teslas pack weights. They are likely pushing to go lower than that. I think it's not crazy to consider they're targeting a production weight ~50% below your guess - in the high 3000s)
5. On top of fuel savings, one of his more compelling points is that maintenance on their engines will be much, much lower. Jet engines are expensive to service, maintain, and repair (thousands of parts, complicated designs, extreme operating conditions). Their motors are basically 450kg dc motors - it's a giant drone motor mounted on an airframe.
6. they seem to have quite a bit of interest from existing airlines (ex - united) so apparently this does seem compelling to them.
7. He quotes a $5 take-off cost in electrical power. Something like an Embraer ERJ-135 uses ~20 - 30 gallons of jet fuel for the same thing (~$100). If they target a plane that's doing very frequent takeoffs/landings, operating costs could be considerably lower, not just lower.
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Personally - I don't know if they'll make it work, but it's definitely an interesting play, with more real thought put into it than most attempts I've seen.
4. Remember my predicted number is on the low side of how much juice they would need. Of course they get much better efficiency than a conventional jet on taxi and takeoff, so maybe it ends up being closer to what you are saying. I wish they had some more hard data.
5. Yep, commented on this in another post but even just removing takeoff wear and tear on a conventional engine would be big.
6. I would take that with a big dose of salt. United has a deal with Boom (a complete fraud of a company in my view) to purchase planes. So maybe not the best metric.
7. I haven't done the math but the $5 takeoff doesn't pass the smell test for me. $5 doesn't buy much juice (50 kWh? So like a gallon of jet fuel?) and getting a 30k+ lb plane to cruising altitude is not trivial.
"Personally - I don't know if they'll make it work, but it's definitely an interesting play, with more real thought put into it than most attempts I've seen."
Totally agree, which I never thought I would say about an aerospace startup.
A businessman I talked to said that United is investing in smaller airplane manufacturers in hopes of breaking the Boeing-AirBus duopoly. Thus, giving commitments here and to Boom Supersonic.
Check jet engine weight and include in the calculation. One weights 2200-3700 lbs according to same source that quotes 45.9 seat miles per gallon. Vs 125 pounds for electric engine.
I’d guess comparable for a 30-seat regional, you’d probably want to compare with a PT6, especially since this aircraft is prop driven. That’s only about 250lb dry.
The thing I quoted is more for bigger jets with much larger engines (it was the first reasonable looking source I found). In any case their hybrid has four engines, two electric, two conventional, so you are really should think of it as needing to haul two extra engines on top of what a conventional only jet would have.
There are a lot of trucks that never go very far in a day. Many of them are used for "last mile" delivery. They start at a warehouse, get loaded, then go make a few deliveries and head back for the next load. While fast charging is needed, they don't go very far and thus don't need extreme range.
It is a valid question though: how do we get more of the long distant freight onto trains. Followed closely by how to we get existing freight trains to move to all electric instead of diesel electric (I've been told railroads have studied this: if diesel gets to $8/gallon it is cost effective - but I can't find any references to cite and so you should take this "Fact" with some salt)
Fast charging probably isn't really necessary for last mile delivery trucks. They usually work about 8-10 hours a day then spend the majority of their time sitting in a lot or garage. Perfect time to charge them.
yes i conceded that use case a bit bellow, it mostly makes sense in dense urban areas, where access to the grid is easy, and not emitting polution is at a premium. But even then it's a very difficult case to make before eg: electrifying buses, or more generally, decarbonising your electricity supply. If this made sense, musk tried to sell it a decade ago, it just doesn't. A lot of the value is that the majority don't understand the tradeoffs and complication, and just think electric = more green, and it makes for great PR specially abroad.
What China does hardly indicates economic sense, and you can be sure you won't hear about the down sides or failures. They already very agressively hide car lithium fires but they're very frequent. Economics over there are mostly investment driven with a large dose of ideology and vanity, not demand driven. You can see it everywhere including the massive amounts of empty housings for example
Being dependent on (cheap) oil can make economic sense as well. Unless you get cut off all of a sudden. Depending on local energy might make more sense in the long term. also for factor other than the economy.
and you are refuting with even less justification. I told you how to check for yourself if you actually cared about veracity. Best of luck trying to get funding to publish something academic anti-CCP though, but I'd love it if you did. Also this is just a conversation, not an academic debate
This ignores the fact that there are also things that China does better or equal than Western companies. Like robots, solar panels, electric cars (?), AI models, electronics.
They must be good at something, otherwise China wouldn't be where it is.
So flat out dismissing anything from China is not enough of an argument.
Mind you, I'm not saying you're generally wrong, just your "generally" is wrong. ;-)
I'd dispute they do any of those better, they stole the IP, then used public funds to make cheaper versions in the hope of leading the markets, including by being artificially more affordable while there is any competition. Besides electric cars and solar, it's very debatable wether those will actually be ecological in the end. For ex. they are still opening massive amounts of fossil based electric plants, so the truck that is half battery is actually running on coal anyway. It would take an incredible re-work of the electric grids to accomodate actually transitioning away from thermal cars, including some solution for seasonal storage. If you're impressed by their robots, I don't know what you're looking at, they seem to be ridiculous, not even at the tech level that boston dynamics had decades ago. Finally keep in mind that electric cars are fantastic spying devices, for collecting data, and if you're nefarious, imagine hacking into them. That's why teslas are banned near anything governmental in China. So there is a huge strategic advantage to cornering that market, but not really to save the planet. The AIs are all distilled, USA still leads by far there, and they too are strategic weapons
You're making a lot of assertions without citations here.
If I look at a BYD at my local dealership, and compare it to a comparable spec German car (I live in the UK, so tariffs are not the thing shifting the needle here), I can see where the cost savings are and the trade-offs.
I don't think they're artificially more affordable. I just think they're more affordable.
Using public funds to invest in capital expenditure is - outside of the US - considered a wise use of public funds. If the result is a more competitive industry, whether that's ship building (South Korea), steel production (recent UK nationalisation efforts), military hardware (United States), or medical research, physics, chemistry, computing (look at the history of all the G7 there), and so on, and so on... irrelevant.
China has decided to spend it on complex manufacturing that they've been the supply chain for to Western manufacturers for the last 30 years. That's not controversial - it's been obvious this is where they were heading for some time.
First off, I admit I have no idea what the EU and US car manufacturers are doing, their positions for the past decade don't make any sense to me in the electric market. Actually smells like hubris and inertia more than anything to be honest.
I'm not being super academic with citations, but the CCP investments in BYD, to the point it makes no sense to exist without aren't exactly hard to find secrets.
You're not comparing comparable things, in the UK, there is a great deal of expectations of what an employee has as rights for instance. There are extremely rigorous safety regulations that are very onerous. We can debate wether those are justified but it's a very complex topic you're brushing off. Their innovation seems mostly on small iterative gadgets, but look more closely into what they tolerate as self driving and the death it causes, and be sure you want that in the UK for profit margins.
I'm really not against neither subsidies nor artificially inflating one's strategic advantage at all to develop a market and corner the competition. I never said China is wrong to do what it's doing. What I am saying is that its dangerous for us outside of China to buy into it now. Beyond the security implications of chinese robots with sensors everywhere roaming about cities the CCP considers their ennemies, there's just the dependency risk, there's the "how much do you trust the people who fed paint to their babies to handle super dense explosives that cant be put out by water in dense cities", and the basic question, maybe its better to have the lightest car possible, not the most gadgetty with drones and ipads.
So the basic point above "China has more electric trucks therefore it makes economic sense" is helped by none of this
It's trivial to compete if you don't have R&D costs, and don't care about stuff like your employees, regulations or safety, or even sales since you can just use government money (this is not without consequence either). And it's not only about free market stuff, why do you think they're so excited for all countries to use their 5g products for example ? Don't think this is benign.
There are plenty of legitimate criticisms of Chinese policy, but you should probably reread your arguments and check for coherence.
Chinese EV trucks make no economic sense even though they're 30% of China's fleet but also they're only investing all that as a trojan horse even though they use them almost exclusively domestically, plus the old "Asians don't innovate they just copy" canard even though there wasn't much Western IP on electric trucks to copy in the first place and China's battery technology is somehow not Alibaba knockoffs but more performant than Western equivalents (whilst state sponsored Chinese industries remain generations behind in stuff that's actually strategically critical for them to clone via industrial espionage like semiconductors and jet engines)
I really don't see the contradiction, if that 30% was true, which, really... but ok, it still would normal for the CCP to do stupid stuff because they think it makes them look modern or ecological or similar. That's why there's no need for economic sense to explain that development at all. There are also excellent non financial reasons to want to dominate that market. So to circle back, their use of trucks, which if you buy the 30% "omg lol" as they say, is in no way an argument to them making sense, neither economically nor ecologically.
> used public funds to make cheaper versions in the hope of leading the markets, including by being artificially more affordable while there is any competition
If you replace 'public' with 'VC', isn't that the exact same as the US does in Silicon Valley?
They're really not, the tiniest bits have shown with evergreen for ex, all the ghost cities. We don't really see the people who's savings, which with kids is the only "pension", have been demolished, on an individual level Chinese tend to save way more than others, this is gone. There's the demographic issue on top, the famines, that they import 70% of their food, depend on trade which the americans are withdrawing for protecting the routes of, and other unadressed issues because the priority is this investment, the missing population, the utter lack of statistics, even internally. Most likely the biggest factor will be wether they try something in Taiwan next year as they warned.
And opened about 80GW of coal last year alone. That's the only advantage to electric trucks, they can run on coal too, even though you can only carry half the capacity whilst moving the same total weight, it still can make sense, just not economic and certainly not ecological. They sure love people writing articles about it though, and how green and solar they are.
neither of those are true, if they were, remember when tesla wanted to sell trucks like 10 years ago ? if you use electric trucks, half the mass you pay to move around is useless. Also the grid isn't "half coal", the truck doesn't wait for the sun to come out to charge. Which is another cost to transporters: the hours of downtime to recharge. They only make very limited sense in very last mile scenarios in dense cities. Also coal is way worse to burn than petrol, and in China's case, it's mostly bituminous, one of the worst coals in terms of pollution.
Solar is only about 13% of China's power. They have hydro, wind, nuclear and gas too as well as coal.
Their off peak prices have generally been overnight, ideal for truck charging, though they have started having them around noon too like many other nations with growing solar share. Great for a mid shift top-up.
Coal is worse to burn than gasoline, but a car engine throws 80 percent of that away so you have to burn more compared with an efficient EV.
This has all been debated to death for over a decade, MIT has interactive tools to calculate figures, there's really no excuse for not knowing this about a subject you are so passionate about.
I never said anything about green. They don't have oil, they want to be less reliant on oil. Electricity allows them to adapt the mix in a way petrol doesn't.
I have had goodluck with this and have gotten many pieces of furniture that will last for the rest of my life used. It is very hit or miss based on your location though and it does restrict your style choices.
I can't stand Ikea furniture quality but am often confronted with the only option for higher quality being an order of magnitude more expensive. Where is the middle ground between a Stickley Morris chair and an Ikea chair?
Also their particleboard and cardboard furniture should be banned. Furniture should not dissolve when a drink gets spilled on it.
When I moved from LA to St Louis many years ago, there wasn’t an IKEA yet. I was truly confused about where one was supposed to go to buy lamps. Any furniture stores that had them were selling ones that gave off strong grandma vibes.
The full title of the video is, "Dr. Bob Abernethy Never Told Tales of Blackbirds U2s and Roadrunners the Golden Age of Aerospace". I couldn't fit that so I hope this is a reasonable substitute.
Dr. Abernethy, who passed in 2021, is probably known in the aerospace world more for Weibull analysis (1) than his J58 work, atleast that was the case for me before finding this. Anyone who is an enthusiast of the SR-71 will find it interesting.
(1) A type of analysis used widely to predict failures with limited test or field data.
But if you told an embodied AI to do a home cleaning task knowing it's a possibility it will decide to pick up a gun and start spraying bullets, then society has an interest in holding you liable.
Is that the case, though? This is all pretty new tech. Did people know the machine was dangerous and didn't care, or did they not anticipate such a behavior?
It's artificial intelligence. If you treat something like a person and delegate to it, how can you later say you didn't trust it would execute your commands faithfully? And how wouldn't you be negligent in delegating a task to new, unproven tech?
Because that's how technology goes from being new to being understood. People try it, see what it can do, what it's good for, and in what ways it's dangerous, if any.
So if I make a new object that can kill you, I can try it, see what it can do, etc without liability? We already have computer programs that inflict damage on computers. Is AI new in that regard?
If companies are spending so many resources on "alignment" can they argue that they didn't know the risks of their research?
Hard to make a case in 2026 that you can be oblivious to the potential of AI to do unexpected things that could impact other people.
"Did people know the machine was dangerous and didn't care, or did they not anticipate such a behavior?"
This framing of the issue as binary being either intentional negligence or blissful ignorance is not how liability works. If you are working with something potentially dangerous and impactful to society you no longer get to say "I didn't know" because we as a society hold you to a higher standard for getting the privilege of working with the potentially dangerous and impactful thing. Doctors, lawyers, engineers, pilots, truck drivers, etc. are all examples of this.
A trucker whose brakes fail causing a crash is liable even if the failure wasn't caused by intentional negligence because we hold them responsible to make sure they won't fail to begin with. A programmer and company whose safety measures fail resulting in a program hacking another company should absolutely be held accountable.
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