To recap, based on financial statements the company:
used to be a "waste management" company that failed and was sold as a "public shell" to enable the formerly private company to go public and sell shares (the waste management business it was engaged in was an effort to commercialize a process to treat low-level nuclear waste developed by Russian scientists)
has $64 mil in debt apparently unrelated to aviation
has spent $3.8 mil on R&D for this project
has 8 R&D employees
only 2 of those 8 have any evident experience related to designing aircraft
650 mile range may not be as much as it sounds like. I'm not a pilot but I know there are regulations for reserve fuel.
So you need enough fuel (kWH in this case) for taxi, take off, the trip itself, divert to alternate airport, plus reserve for 30-45 minutes of holding, at least one missed approach/go-around, plus maybe more emergency reserve beyond that. It might add up to only 300-400 of practical travel range.
Turboprops are usually sub 2-hour flights; 400 miles would be 80 minutes, which covers most of the passenger flights a turboprop might do.
Another question might be whether or not the range can be extended when there are no passengers; a turboprop can be loaded with extra fuel when only the plane needs to be moved; the beechcraft super king (10 pax turboprop) has nearly a 2000 mile range with no passengers.
It was also slightly shady to specify the range in miles, when nautical miles are more typically used.
650 miles is a wishing number with a full passenger load based on current battery technology. When the unexpected weight increases that impact every new aircraft design inevitably hit, that theoretical range will drop significantly.
I’m curious what voltage the pack runs at and how long it would take to charge. Many of these types of aircraft operate in FAR Part 135 on-demand operations. Aircraft and crew utilization are crucial for the business model.
Expensive airplanes and pilots don’t make money sitting on the ground. Of course, if operating costs (fuel) are a fraction of a traditional aircraft then margins get better but do they get good enough to offset 2-3x more aircraft and pilots to operate those aircraft to be able to fulfill demand?
I hate to sound like the people who constantly naysay electric cars because of charging times but in this industry turn around time is crucial.
>I’m curious what voltage the pack runs at and how long it would take to charge. Many of these types of aircraft operate in FAR Part 135 on-demand operations. Aircraft and crew utilization are crucial for the business model.
This is the number one question I had as well, for the same reasons. Porsche has a 1000V system in their new Taycan EV, so I'd assume they're at least at that level. At 900kWh, a system like that could charge from 10% (assumed minimum reserve) to 95% (Batteries are never really charged to 100%) in under 2 hours @ 400KW, which is about the power level of the beefiest EV chargers being developed right now.
More likely they will have swappable batteries, which makes a lot more sense from a thermal management point of view as well. You can either load up the pack with all kinds of cooling and deal with the added weight, or just make it passive air-cooled and swap it out between flights before it gets too hot.
> I’m curious what voltage the pack runs at and how long it would take to charge
It's surely not a new battery chemistry. Lithium cells have a voltage in the 3-3.5V range. If you want more, you put them in series. And fed with an appropriately regulated supply, all common cell types will charge to full capacity from empty in 4 hours or so, reaching 50% sometime inside of 1 hour (that is, most of the time spent is in "topping off" the thing, broadly you can get energy into a battery at least as fast as you can get it out). It's literally no different than your phone battery.
They are claiming a price of $3 million plus. While that sounds like a lot, from what I can tell it is cheap for aircraft of that size. (it is very hard to track down prices for new aircraft so feel free to correct me). It may well be feasible to buy 3 of these to replace 1 of something else, and have 2 charging all the time.
These cost reductions are a big deal and they are largely based on energy cost reductions. It offsets some of the inconveniences of not so long range, lack of infrastructure for charging, and having to wait for recharging.
For reference, typical business jets or twin props burn hundreds of gallons of fuel on a single trip costing hundreds of dollars. They also need frequent maintenance as there are a lot of things that need to be checked and fixed with such planes. So, the proposition of charging with cheap electricity and getting rid of most of the stuff that needs fixing and maintaining on a regular basis is highly attractive. If it works as advertised, this plane will sell like crazy. Electrical engines basically last a very long time and are easy to check and service. Charging batteries is comparatively cheap to burning fuel and likely to get cheaper in the future.
Practically speaking, if you have a home base with charging infrastructure but most other airports do not (yet), effectively you are looking at a 300M range for a return trip unless you are flying to a place with infrastructure to charge. That's still fairly nice.
For commercial operations, there are plenty of use-cases that would be well served by a plane like this. A plane like this gets passenger cost down to something that is quite competitive with a train ticket.
Jet engines are conceptually simple and very low maintenance but still very expensive. Difficult materials and high precision. And use a massive amount of fuel.
It is fascinating to compare with an electric aircraft. It's not so clear to me what the economics would be like as a whole.
It's not just fuel but investment and maintenance cost.
To me it might make sense in a short high frequency operation. Like to some island. Not as a business jet that mostly just sits around.
Audi also introduced a concept eVTOL with detachable "pod". It's an interesting design choice. Creating modular components that could be shipped across air, sea, and land boundaries.
For reference: Model 3 apparently has 75 to 100 kWh. This plane seems to spec out - Li-lon - 900 kWh. For a layman, it sounds like 9 times the battery weight of a Model S flying in the sky...
Wonder how they made it light enough to be able to fly...
>Wonder how they made it light enough to be able to fly...
You get a massive weight savings in the engines and all related components. DC motors are multiple times smaller and lighter than the equivalent powered turbine engine when you consider the entire system. On top of that you totally eliminate the need for variable pitch props and the related transmission parts since electric motors can adjust power instantly. You also negate a lot of hydraulic systems (and their redundant backups) without the need for things like fuel pumps, thrust reversers, etc.
It also seems they are not using anything like standard li-po tech. From their site:
>Utilizing industry-leading lithium-ion batteries and a proprietary Aluminum-Air system for range, we’ve surpassed the 400Wh/kg mark.
For reference this is nearly double Tesla's energy density. Of course the cells will be much more expensive, but that matters a lot less for a low volume, high usage application that can be amortized.
The airframe of airplanes is surprisingly lightweight. Engine(s) can easily be around 25% of the (empty) weight, and on anything with decent range, the fuel dominates. Both necessitates a lot of supporting infrastructure.
The airplane can probably pack battery cells much denser than Tesla. Tesla uses active, liquid-based cooling; an airplane could employ the airstream for that. Plus I expect a lot less of battery heating; while the capacity is 9x of Model 3, the engine power (thus electrical drain) is around just 3x of Model 3. [1]
Also the metal shield under the battery can probably be done away with.
As others pointed out, electric engines are much different beast than any hydrocarbon burning ones. You need less support structure (for starters, less vibrations) and also much less auxiliary gear; think of all the cooling systems (either liquid cooling or flaps & openings & shrouds to direct air around); fuel tankage, pipes, valves, pumps & booster pumps; electric generator & possibly hydraulic pumps, and lots and lots of wires to both send electricity and control signals. As electric engines are essentially low-maintenance, you'd save a bunch of weight on monitoring instrumentation & servicing access panels. Maybe i'm reading too much into the renders, but the engine- and prop cowls seem to be very tight fit; both lessening drag and also simply being smaller, lighter parts.
Lastly, electric engines can typically be over-loaded way over their continuous power for well understood short stretches of time, facilitating extra power for prompt & safe take-off. Not so with piston or jet engines; the take-off power is typically maybe a dozen percent more than the rated continuous power, and that's about it. You end up carrying through the whole flight engines over-sized (and thus over-weight) just for the sake of take-off power.
Small weights savings all over the airframe add up.
That's an interesting statistic. According to Wikipedia, the Tesla's battery is around 500kg, so the aircraft is carrying around 4500kg in batteries. For comparison, the 10-seat Cessna 404 Titan weighs just 2200kg when empty and has a max take-off weight of 3800kg. So the battery alone weighs more than a similar Cessna, full of pax, luggage and fuel. Hm.
They list a MTOW of 6350 kg. Less 800kg for 10 fully clothed adults and the weight of the battery, there's only 1000kg left for the plane. Maybe that's possible?
Good question. The Model 3 battery[1] weighs 478 kg so 9x = ~4,300kg. 11 people on board is another 1,000kg (not including the golf clubs). MTOW[2] is 6,350kg so the airframe needs to weigh in at ~1,000kg.
I'm sure they can make a battery lighter than a Model 3 battery (optimized for weight rather than cost), but how much lighter???
Unlike liquid fueled aircraft, you won't be able to trade off fuel weight for passenger weight to stay under MTOW.
The article makes it sound like it is made from commoditised components of today.
Given how similar it sounds to that of a Tesla Model S + SpaceX - Battery, Electric motor, propeller and such, Why wouldn't Tesla attempt such a thing based on components they already build for Tesla or SpaceX?
While on Joe Rogan's podcast Elon Musk did say he had the design for a VTOL electric plane that regained the energy used for lift on descent. I was a little bit more than intrigued by that.
Tesla should focus on building cars first. They have enough supply chain issues that getting into the general aviation market would be spreading far too thin.
> But this isn’t another claim by another overoptimistic purveyor of electric dreams.
Really? So, it's built and demonstrated?
> the first planes are being built right now.
Oh, so when you say “Eviation’s Alice is an all-electric, nine-person aircraft” you mean “Eviation claims Alice will be an all-electric, nine-person aircraft” and when you say “this isn’t another claim by another overoptimistic purveyor of electric dreams” you mean “this probably is another claim by another overoptimistic purveyor of electric dreams.”
TFA claims electric planes are quieter, but I thought the majority of the noise from a turboprop was caused by the propeller. Does anyone have actual knowledge of the noise difference?
> and they receive power from a 900 kWh lithium ion battery pack.
Wow! One of the amazing things about EVs is how easy it makes it to reason about the energy usage. That’s about $250 in energy here in CA. I might produce a mW of energy with my solar panels on a good month here.
If it actually has a range of 650 miles then that comes out to be about 50c a mile, which would be quite amazing.
It has 3 engines, one is at the tail. While I agree in principle, I think having just one engine at the tip of the wing left running is going to be a rare event.
So, Al-air battery. While it may be not practical for a car (even just once in 2000 miles as those prototypes), refueling the plane by reloading with fresh aluminum would be just ok. My bet was on Li- or K-air, yet I'd take the Al one for starters.
Exciting - remember that battery tech is still in the early days, it will only get cheaper, more energy dense, and more reliable. If this company doesn't succeed, it will get better soon.
I do like the v-tail look. Not sure on the pros and cons of the approach, but it's my favorite tail style of aircraft (if one keeps track of such things)
[+] [-] tristanb|7 years ago|reply
https://twitter.com/BenBrelje_says/status/106484220091004108...
https://twitter.com/BenBrelje_says/status/106485722028904038...
https://twitter.com/BenBrelje_says/status/106491195862390374...
To recap, based on financial statements the company:
used to be a "waste management" company that failed and was sold as a "public shell" to enable the formerly private company to go public and sell shares (the waste management business it was engaged in was an effort to commercialize a process to treat low-level nuclear waste developed by Russian scientists)
has $64 mil in debt apparently unrelated to aviation
has spent $3.8 mil on R&D for this project
has 8 R&D employees
only 2 of those 8 have any evident experience related to designing aircraft
[+] [-] ams6110|7 years ago|reply
So you need enough fuel (kWH in this case) for taxi, take off, the trip itself, divert to alternate airport, plus reserve for 30-45 minutes of holding, at least one missed approach/go-around, plus maybe more emergency reserve beyond that. It might add up to only 300-400 of practical travel range.
[+] [-] Groxx|7 years ago|reply
[1]: https://www.eviation.co/alice/
[+] [-] aidenn0|7 years ago|reply
Another question might be whether or not the range can be extended when there are no passengers; a turboprop can be loaded with extra fuel when only the plane needs to be moved; the beechcraft super king (10 pax turboprop) has nearly a 2000 mile range with no passengers.
It was also slightly shady to specify the range in miles, when nautical miles are more typically used.
[+] [-] nradov|7 years ago|reply
[+] [-] bronco21016|7 years ago|reply
I’m curious what voltage the pack runs at and how long it would take to charge. Many of these types of aircraft operate in FAR Part 135 on-demand operations. Aircraft and crew utilization are crucial for the business model.
Expensive airplanes and pilots don’t make money sitting on the ground. Of course, if operating costs (fuel) are a fraction of a traditional aircraft then margins get better but do they get good enough to offset 2-3x more aircraft and pilots to operate those aircraft to be able to fulfill demand?
I hate to sound like the people who constantly naysay electric cars because of charging times but in this industry turn around time is crucial.
[+] [-] aphextron|7 years ago|reply
This is the number one question I had as well, for the same reasons. Porsche has a 1000V system in their new Taycan EV, so I'd assume they're at least at that level. At 900kWh, a system like that could charge from 10% (assumed minimum reserve) to 95% (Batteries are never really charged to 100%) in under 2 hours @ 400KW, which is about the power level of the beefiest EV chargers being developed right now.
More likely they will have swappable batteries, which makes a lot more sense from a thermal management point of view as well. You can either load up the pack with all kinds of cooling and deal with the added weight, or just make it passive air-cooled and swap it out between flights before it gets too hot.
[+] [-] taneq|7 years ago|reply
[+] [-] ajross|7 years ago|reply
It's surely not a new battery chemistry. Lithium cells have a voltage in the 3-3.5V range. If you want more, you put them in series. And fed with an appropriately regulated supply, all common cell types will charge to full capacity from empty in 4 hours or so, reaching 50% sometime inside of 1 hour (that is, most of the time spent is in "topping off" the thing, broadly you can get energy into a battery at least as fast as you can get it out). It's literally no different than your phone battery.
[+] [-] bluGill|7 years ago|reply
[+] [-] unknown|7 years ago|reply
[deleted]
[+] [-] lolc|7 years ago|reply
> aims to have one flying early next year.
Using the present tense is not justified.
[+] [-] tristanb|7 years ago|reply
https://news.ycombinator.com/reply?id=18620766&goto=item%3Fi...
[+] [-] Groxx|7 years ago|reply
> The company plans to fly a prototype of the “Alice” design at the Paris Air Show in June ...
So yea, seems premature, since they're getting close to a prototype.
[1]: https://www.bloomberg.com/news/articles/2018-11-12/pioneerin...
[+] [-] Robotbeat|7 years ago|reply
[+] [-] shaki-dora|7 years ago|reply
[+] [-] jillesvangurp|7 years ago|reply
For reference, typical business jets or twin props burn hundreds of gallons of fuel on a single trip costing hundreds of dollars. They also need frequent maintenance as there are a lot of things that need to be checked and fixed with such planes. So, the proposition of charging with cheap electricity and getting rid of most of the stuff that needs fixing and maintaining on a regular basis is highly attractive. If it works as advertised, this plane will sell like crazy. Electrical engines basically last a very long time and are easy to check and service. Charging batteries is comparatively cheap to burning fuel and likely to get cheaper in the future.
Practically speaking, if you have a home base with charging infrastructure but most other airports do not (yet), effectively you are looking at a 300M range for a return trip unless you are flying to a place with infrastructure to charge. That's still fairly nice.
For commercial operations, there are plenty of use-cases that would be well served by a plane like this. A plane like this gets passenger cost down to something that is quite competitive with a train ticket.
[+] [-] Gravityloss|7 years ago|reply
It is fascinating to compare with an electric aircraft. It's not so clear to me what the economics would be like as a whole.
It's not just fuel but investment and maintenance cost.
To me it might make sense in a short high frequency operation. Like to some island. Not as a business jet that mostly just sits around.
[+] [-] ArtWomb|7 years ago|reply
https://www.autoblog.com/2018/11/28/audi-demonstrates-pop-up...
[+] [-] reacharavindh|7 years ago|reply
Wonder how they made it light enough to be able to fly...
https://www.eviation.co/alice/
[+] [-] aphextron|7 years ago|reply
You get a massive weight savings in the engines and all related components. DC motors are multiple times smaller and lighter than the equivalent powered turbine engine when you consider the entire system. On top of that you totally eliminate the need for variable pitch props and the related transmission parts since electric motors can adjust power instantly. You also negate a lot of hydraulic systems (and their redundant backups) without the need for things like fuel pumps, thrust reversers, etc.
It also seems they are not using anything like standard li-po tech. From their site:
>Utilizing industry-leading lithium-ion batteries and a proprietary Aluminum-Air system for range, we’ve surpassed the 400Wh/kg mark.
For reference this is nearly double Tesla's energy density. Of course the cells will be much more expensive, but that matters a lot less for a low volume, high usage application that can be amortized.
[+] [-] dexen|7 years ago|reply
The airplane can probably pack battery cells much denser than Tesla. Tesla uses active, liquid-based cooling; an airplane could employ the airstream for that. Plus I expect a lot less of battery heating; while the capacity is 9x of Model 3, the engine power (thus electrical drain) is around just 3x of Model 3. [1] Also the metal shield under the battery can probably be done away with.
As others pointed out, electric engines are much different beast than any hydrocarbon burning ones. You need less support structure (for starters, less vibrations) and also much less auxiliary gear; think of all the cooling systems (either liquid cooling or flaps & openings & shrouds to direct air around); fuel tankage, pipes, valves, pumps & booster pumps; electric generator & possibly hydraulic pumps, and lots and lots of wires to both send electricity and control signals. As electric engines are essentially low-maintenance, you'd save a bunch of weight on monitoring instrumentation & servicing access panels. Maybe i'm reading too much into the renders, but the engine- and prop cowls seem to be very tight fit; both lessening drag and also simply being smaller, lighter parts.
Lastly, electric engines can typically be over-loaded way over their continuous power for well understood short stretches of time, facilitating extra power for prompt & safe take-off. Not so with piston or jet engines; the take-off power is typically maybe a dozen percent more than the rated continuous power, and that's about it. You end up carrying through the whole flight engines over-sized (and thus over-weight) just for the sake of take-off power.
Small weights savings all over the airframe add up.
--
[1] https://en.wikipedia.org/wiki/Tesla_Model_3#Specifications - 258 kW for Model 3 AWD, vs 3x260kW for the airplane.
[+] [-] jetrink|7 years ago|reply
They list a MTOW of 6350 kg. Less 800kg for 10 fully clothed adults and the weight of the battery, there's only 1000kg left for the plane. Maybe that's possible?
[+] [-] gvb|7 years ago|reply
I'm sure they can make a battery lighter than a Model 3 battery (optimized for weight rather than cost), but how much lighter???
Unlike liquid fueled aircraft, you won't be able to trade off fuel weight for passenger weight to stay under MTOW.
[1] https://evannex.com/blogs/news/tesla-s-battery-pack-is-both-...
[2] https://en.wikipedia.org/wiki/Maximum_takeoff_weight
[+] [-] reacharavindh|7 years ago|reply
Given how similar it sounds to that of a Tesla Model S + SpaceX - Battery, Electric motor, propeller and such, Why wouldn't Tesla attempt such a thing based on components they already build for Tesla or SpaceX?
[+] [-] Beltiras|7 years ago|reply
[+] [-] woah|7 years ago|reply
[+] [-] briandear|7 years ago|reply
[+] [-] unknown|7 years ago|reply
[deleted]
[+] [-] dragonwriter|7 years ago|reply
Really? So, it's built and demonstrated?
> the first planes are being built right now.
Oh, so when you say “Eviation’s Alice is an all-electric, nine-person aircraft” you mean “Eviation claims Alice will be an all-electric, nine-person aircraft” and when you say “this isn’t another claim by another overoptimistic purveyor of electric dreams” you mean “this probably is another claim by another overoptimistic purveyor of electric dreams.”
[+] [-] aidenn0|7 years ago|reply
[+] [-] dev_dull|7 years ago|reply
Wow! One of the amazing things about EVs is how easy it makes it to reason about the energy usage. That’s about $250 in energy here in CA. I might produce a mW of energy with my solar panels on a good month here.
If it actually has a range of 650 miles then that comes out to be about 50c a mile, which would be quite amazing.
[+] [-] billbrown|7 years ago|reply
[1] https://zunum.aero/ [2] https://www.youtube.com/watch?v=A1ioXfa_jpY
[+] [-] clueless123|7 years ago|reply
[+] [-] avmich|7 years ago|reply
[+] [-] trhway|7 years ago|reply
[+] [-] Latteland|7 years ago|reply
[+] [-] mysterydip|7 years ago|reply
[+] [-] miahi|7 years ago|reply
[1] https://www.eviation.co/alice/
[+] [-] Justin_K|7 years ago|reply