8 ms·

Eviation’s Alice is an all-electric, nine-person aircraft

lolc 8y ago
Is? No it's not. It could be. > aims to have one flying early next year. Using the present tense is not justified.
- shaki-dora 8y ago
  Bilbo Baggings is a Hobbit.
  - azag0 8y ago
    Words are used in a context which shapes their meaning. “Is” there implies to most that the aircraft already exists.
    - em3rgent0rdr 8y ago
      “It depends on what the meaning of the word ‘is’ is.”
      - azag0 8y ago
        Well, he was right about that, although there is little doubt his intent was to deceive.
  - lolc 8y ago
    Are you saying that the headline obviously belongs to the fantasy domain?
  - gpm 8y ago
    Bilbo Baggins currently exists, as a fantasy character. The character in my new novel Tina Taggins will be a gnome though. I haven't written in that character yet. "is" vs "will" is a tense thing. This isn't yet a plane like Tina Taggins isn't yet a character in my novel so "will" is a appropriate.
    - delinka 8y ago
      There is no third “g” in Bilbo’s last name.
      - gpm 8y ago
        Thanks, fixed.
- Robotbeat 8y ago
  They're building it now, so it exists in some form already if not complete.
  - Piskvorrr 8y ago
    Sure. Flying cars just around the corner, for a century now. Not holding my breath.
- Groxx 8y ago
  also Bloomberg[1] mentions this: > 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/pioneering-electric-plane-needs-200-million-for-final-push https://www.bloomberg.com/news/articles/2018-11-12/pioneerin...
- tristanb 8y ago
  It's never going to fly, its a scam. https://news.ycombinator.com/reply?id=18620766&goto=item%3Fid%3D18602771%2318620766 https://news.ycombinator.com/reply?id=18620766&goto=item%3Fi...
mysterydip 8y ago
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)
- miahi 8y ago
  Probably because it has a third propeller in the tail - not easy to spot in the article's photo, but you can see it better on their site[1]. [1] https://www.eviation.co/alice/ https://www.eviation.co/alice/
  - amelius 8y ago
    Photo? You mean CGI ...
  - perilunar 8y ago
    That rear propeller will be screwed by anything kicked up by the main gear. And good luck with rotation on take off, and landing flare. Also, the adverse yaw if you lose one of the wingtip motors or propellers will be severe.
    - dotancohen 8y ago
      I agree with you about rotation. The main gear is so far forward of that prop that I'm actually wondering if this thing doesn't rotate, like the B-52. As for landing flare, those wings aren't holding any fuel so they are razor thin. I'm having a hard time deciding about when they stall. But I don't see asymmetrical thrust as being a real problem on this plane. It has far fewer moving parts than the single- or dual- motor props that it aims to replace. This is not an ETOPS aircraft, and even if an outboard motor fails you still have that central pusher to help. Back to those razor-sharp wings: they are quite long and it looks like this plane would have a mighty fine glide ratio.
reacharavindh 8y ago
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?
- woah 8y ago
  Why doesn’t Tesla make flashlights too?
- Beltiras 8y ago
  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.
  - captainperl 8y ago
    Airplanes always get most of the energy from ascent back in descent. VTOL will get less back because it's grossly inefficient. Note that drag needs to be deducted from the potential energy. There's parasitic and induced drag.
    - Beltiras 8y ago
      His context was that the energy was returned to the battery, not in the laws-of-thermodynamics sense.
    - lmm 8y ago
      > Airplanes always get most of the energy from ascent back in descent. Given that the aeroplane ends up stopped on the tarmac at (approximately) sea level with (approximately) empty tanks, how so? A bit of heat I suppose but that's not usable. I'd say current aeroplanes generally deliberately dump energy to the environment (via deliberately increased drag, spoilers etc.) during descent, no?
      - 8y ago
reacharavindh 8y ago
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... https://www.eviation.co/alice/ https://www.eviation.co/alice/
- gvb 8y ago
  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. [1] https://evannex.com/blogs/news/tesla-s-battery-pack-is-both-mysterious-and-alluring-work-in-progress https://evannex.com/blogs/news/tesla-s-battery-pack-is-both-... [2] https://en.wikipedia.org/wiki/Maximum_takeoff_weight https://en.wikipedia.org/wiki/Maximum_takeoff_weight
  - bronco21016 8y ago
    Excellent point. Often times only enough fuel for the route is taken so more payload can be taken. In a battery setup your max payload is always the same. No trade offs for range.
  - rhinoceraptor 8y ago
    I would imagine that planes could have much higher battery cell per battery pack utilization, because the protective shell for the battery packs is less necessary. Some back of the envelope math for the Model 3 battery: it has 4416 2170 cells, 66g each, is 291.5 kg, and the total battery pack weight is 478 kg. So only 60% of the battery pack weight is the actual battery cells.
- jetrink 8y ago
  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?
deleted 8y ago
[deleted]
bronco21016 8y ago
Interesting concept. 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.
- taneq 8y ago
  Current electric aircraft like the Pipistrel Alpha Electro (https://www.pipistrel.si/plane/alpha-electro/overview https://www.pipistrel.si/plane/alpha-electro/overview) have swappable battery packs. I can't see why this wouldn't be an option here.
  - Robotbeat 8y ago
    Weight.
- aphextron 8y ago
  >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.
ArtWomb 8y ago
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. https://www.autoblog.com/2018/11/28/audi-demonstrates-pop-up-next-air-taxi/ https://www.autoblog.com/2018/11/28/audi-demonstrates-pop-up...
ams6110 8y ago
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.
- Groxx 8y ago
  I have no idea if this actually covers it or not, but the website[1] claims "Range + IFR reserve: 650 miles". [1]: https://www.eviation.co/alice/ https://www.eviation.co/alice/
- nradov 8y ago
  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.
- aidenn0 8y ago
  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.
aidenn0 8y ago
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?
trhway 8y ago
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.
Latteland 8y ago
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.
dev_dull 8y ago
> 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.
jillesvangurp 8y ago
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.
- Gravityloss 8y ago
  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.
  - jillesvangurp 8y ago
    It's pretty clear what the economics are. Electrical engines are relatively uncomplicated, small, light, and extremely reliable. Also, they tend to last quite long. E.g. in many electrical cars, engine failures or battery replacements tend to be relatively rare and are typically not needed until after hundreds of thousands of miles on the road and usually not because they failed but simply because of degraded performance. With electrical planes you'd expect similar benefits. Maybe a regular quick inspection of the few moving parts for wear and tear, make sure battery performance is fine and that any sensor read outs don't hint at any problems with cooling, performance, etc. Of course you still need to inspect the rest of the plane as usual. However, the engine tends to be one of the more expensive parts normally. Jets are indeed reliable but they do need to be inspected regularly to ensure they stay that way. If e.g. there's some hairline cracks or corrosion, the engine might still work but be about to fail in some spectacular way. Inspections for that are expensive and a regular thing. Same with piston engines. Typically engines are certified for a fixed number of hours before they need their overhaul. I expect similar inspections and overhauls to be needed for electrical engines for the same reasons. But they should be much cheaper to do and the engines could likely be certified for much longer because there is less that can go wrong with them. So, less frequent inspections and overhauls, and cheaper inspections are a good thing. Also replacing parts / engines is likely to be a lot simpler if there are any problems. Other factors are that unused engines tend to need more attention when you take them back into use. E.g. oil can solidify, fuel lines can clog up, etc. Most planes need to be flow regularly in order to avoid extra maintenance cost. To make sure things are functioning, you also have elaborate warmup and runup procedures before take off. A jet or piston engine is not usable until a few minutes after startup when everything is nicely warmed up and properly lubricated. Then you need to typically still go through elaborate runup procedures. Electrical engines are a lot less needy. Also they don't need to warm up, you just flip a switch and they are ready to go. And that's aside from the fuel cost of course, which is a big deal as well.
clueless123 8y ago
With the engines placed at the tip of the wings it must be next to impossible to operate with a single engine.
- avmich 8y ago
  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.
  - abakker 8y ago
    Aviation is all about remaining operational during rare events, though.
    - bluGill 8y ago
      Single engine failure is a rare event that you have to be operational for. Certification generally requires you to be able to take off fully loaded with any one engine off (except single engine planes). If two engines fail you are allowed to turn the rest off and ditch wherever you are. Remember airplanes have a fair amount of glide ability even with no engines. The airplane is coming down, but the pilot has a significant choice as to where and plenty of time to choose between alternatives and get there.
billbrown 8y ago
Zunum Aero is also working in this space.[1] Learned about them through a recent Breakthrough Institute talk. [1] https://zunum.aero/ https://zunum.aero/ [2] https://www.youtube.com/watch?v=A1ioXfa_jpY https://www.youtube.com/watch?v=A1ioXfa_jpY
Justin_K 8y ago
Another aviation rendering... Not going to take it seriously until there's a flying prototype video.
tristanb 8y ago
I'm afraid this is a nonsense. https://twitter.com/BenBrelje_says/status/1064842200910041089 https://twitter.com/BenBrelje_says/status/106484220091004108... https://twitter.com/BenBrelje_says/status/1064857220289040384 https://twitter.com/BenBrelje_says/status/106485722028904038... https://twitter.com/BenBrelje_says/status/1064911958623903744 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
dragonwriter 8y ago
> 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.”

lolc 8y ago

Is? No it's not. It could be. > aims to have one flying early next year. Using the present tense is not justified.

shaki-dora 8y ago
Bilbo Baggings is a Hobbit.
- azag0 8y ago
  Words are used in a context which shapes their meaning. “Is” there implies to most that the aircraft already exists.
  - em3rgent0rdr 8y ago
    “It depends on what the meaning of the word ‘is’ is.”
    - azag0 8y ago
      Well, he was right about that, although there is little doubt his intent was to deceive.
- lolc 8y ago
  Are you saying that the headline obviously belongs to the fantasy domain?
- gpm 8y ago
  Bilbo Baggins currently exists, as a fantasy character. The character in my new novel Tina Taggins will be a gnome though. I haven't written in that character yet. "is" vs "will" is a tense thing. This isn't yet a plane like Tina Taggins isn't yet a character in my novel so "will" is a appropriate.
  - delinka 8y ago
    There is no third “g” in Bilbo’s last name.
    - gpm 8y ago
      Thanks, fixed.
Robotbeat 8y ago
They're building it now, so it exists in some form already if not complete.
- Piskvorrr 8y ago
  Sure. Flying cars just around the corner, for a century now. Not holding my breath.
Groxx 8y ago
also Bloomberg[1] mentions this: > 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/pioneering-electric-plane-needs-200-million-for-final-push https://www.bloomberg.com/news/articles/2018-11-12/pioneerin...
tristanb 8y ago
It's never going to fly, its a scam. https://news.ycombinator.com/reply?id=18620766&goto=item%3Fid%3D18602771%2318620766 https://news.ycombinator.com/reply?id=18620766&goto=item%3Fi...

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)

miahi 8y ago
Probably because it has a third propeller in the tail - not easy to spot in the article's photo, but you can see it better on their site[1]. [1] https://www.eviation.co/alice/ https://www.eviation.co/alice/
- amelius 8y ago
  Photo? You mean CGI ...
- perilunar 8y ago
  That rear propeller will be screwed by anything kicked up by the main gear. And good luck with rotation on take off, and landing flare. Also, the adverse yaw if you lose one of the wingtip motors or propellers will be severe.
  - dotancohen 8y ago
    I agree with you about rotation. The main gear is so far forward of that prop that I'm actually wondering if this thing doesn't rotate, like the B-52. As for landing flare, those wings aren't holding any fuel so they are razor thin. I'm having a hard time deciding about when they stall. But I don't see asymmetrical thrust as being a real problem on this plane. It has far fewer moving parts than the single- or dual- motor props that it aims to replace. This is not an ETOPS aircraft, and even if an outboard motor fails you still have that central pusher to help. Back to those razor-sharp wings: they are quite long and it looks like this plane would have a mighty fine glide ratio.

reacharavindh 8y ago

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?

woah 8y ago
Why doesn’t Tesla make flashlights too?
Beltiras 8y ago
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.
- captainperl 8y ago
  Airplanes always get most of the energy from ascent back in descent. VTOL will get less back because it's grossly inefficient. Note that drag needs to be deducted from the potential energy. There's parasitic and induced drag.
  - Beltiras 8y ago
    His context was that the energy was returned to the battery, not in the laws-of-thermodynamics sense.
  - lmm 8y ago
    > Airplanes always get most of the energy from ascent back in descent. Given that the aeroplane ends up stopped on the tarmac at (approximately) sea level with (approximately) empty tanks, how so? A bit of heat I suppose but that's not usable. I'd say current aeroplanes generally deliberately dump energy to the environment (via deliberately increased drag, spoilers etc.) during descent, no?
    - 8y ago

reacharavindh 8y ago

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... https://www.eviation.co/alice/ https://www.eviation.co/alice/

gvb 8y ago
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. [1] https://evannex.com/blogs/news/tesla-s-battery-pack-is-both-mysterious-and-alluring-work-in-progress https://evannex.com/blogs/news/tesla-s-battery-pack-is-both-... [2] https://en.wikipedia.org/wiki/Maximum_takeoff_weight https://en.wikipedia.org/wiki/Maximum_takeoff_weight
- bronco21016 8y ago
  Excellent point. Often times only enough fuel for the route is taken so more payload can be taken. In a battery setup your max payload is always the same. No trade offs for range.
- rhinoceraptor 8y ago
  I would imagine that planes could have much higher battery cell per battery pack utilization, because the protective shell for the battery packs is less necessary. Some back of the envelope math for the Model 3 battery: it has 4416 2170 cells, 66g each, is 291.5 kg, and the total battery pack weight is 478 kg. So only 60% of the battery pack weight is the actual battery cells.
jetrink 8y ago
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?

deleted 8y ago

[deleted]

bronco21016 8y ago

Interesting concept. 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.

taneq 8y ago
Current electric aircraft like the Pipistrel Alpha Electro (https://www.pipistrel.si/plane/alpha-electro/overview https://www.pipistrel.si/plane/alpha-electro/overview) have swappable battery packs. I can't see why this wouldn't be an option here.
- Robotbeat 8y ago
  Weight.
aphextron 8y ago
>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.

ArtWomb 8y ago

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. https://www.autoblog.com/2018/11/28/audi-demonstrates-pop-up-next-air-taxi/ https://www.autoblog.com/2018/11/28/audi-demonstrates-pop-up...

ams6110 8y ago

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.

Groxx 8y ago
I have no idea if this actually covers it or not, but the website[1] claims "Range + IFR reserve: 650 miles". [1]: https://www.eviation.co/alice/ https://www.eviation.co/alice/
nradov 8y ago
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.
aidenn0 8y ago
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.

aidenn0 8y ago

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?

trhway 8y ago

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.

Latteland 8y ago

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.

dev_dull 8y ago

> 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.

jillesvangurp 8y ago

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.

Gravityloss 8y ago
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.
- jillesvangurp 8y ago
  It's pretty clear what the economics are. Electrical engines are relatively uncomplicated, small, light, and extremely reliable. Also, they tend to last quite long. E.g. in many electrical cars, engine failures or battery replacements tend to be relatively rare and are typically not needed until after hundreds of thousands of miles on the road and usually not because they failed but simply because of degraded performance. With electrical planes you'd expect similar benefits. Maybe a regular quick inspection of the few moving parts for wear and tear, make sure battery performance is fine and that any sensor read outs don't hint at any problems with cooling, performance, etc. Of course you still need to inspect the rest of the plane as usual. However, the engine tends to be one of the more expensive parts normally. Jets are indeed reliable but they do need to be inspected regularly to ensure they stay that way. If e.g. there's some hairline cracks or corrosion, the engine might still work but be about to fail in some spectacular way. Inspections for that are expensive and a regular thing. Same with piston engines. Typically engines are certified for a fixed number of hours before they need their overhaul. I expect similar inspections and overhauls to be needed for electrical engines for the same reasons. But they should be much cheaper to do and the engines could likely be certified for much longer because there is less that can go wrong with them. So, less frequent inspections and overhauls, and cheaper inspections are a good thing. Also replacing parts / engines is likely to be a lot simpler if there are any problems. Other factors are that unused engines tend to need more attention when you take them back into use. E.g. oil can solidify, fuel lines can clog up, etc. Most planes need to be flow regularly in order to avoid extra maintenance cost. To make sure things are functioning, you also have elaborate warmup and runup procedures before take off. A jet or piston engine is not usable until a few minutes after startup when everything is nicely warmed up and properly lubricated. Then you need to typically still go through elaborate runup procedures. Electrical engines are a lot less needy. Also they don't need to warm up, you just flip a switch and they are ready to go. And that's aside from the fuel cost of course, which is a big deal as well.

clueless123 8y ago

With the engines placed at the tip of the wings it must be next to impossible to operate with a single engine.

avmich 8y ago
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.
- abakker 8y ago
  Aviation is all about remaining operational during rare events, though.
  - bluGill 8y ago
    Single engine failure is a rare event that you have to be operational for. Certification generally requires you to be able to take off fully loaded with any one engine off (except single engine planes). If two engines fail you are allowed to turn the rest off and ditch wherever you are. Remember airplanes have a fair amount of glide ability even with no engines. The airplane is coming down, but the pilot has a significant choice as to where and plenty of time to choose between alternatives and get there.

billbrown 8y ago

Zunum Aero is also working in this space.[1] Learned about them through a recent Breakthrough Institute talk. [1] https://zunum.aero/ https://zunum.aero/ [2] https://www.youtube.com/watch?v=A1ioXfa_jpY https://www.youtube.com/watch?v=A1ioXfa_jpY

Justin_K 8y ago

Another aviation rendering... Not going to take it seriously until there's a flying prototype video.

tristanb 8y ago

I'm afraid this is a nonsense. https://twitter.com/BenBrelje_says/status/1064842200910041089 https://twitter.com/BenBrelje_says/status/106484220091004108... https://twitter.com/BenBrelje_says/status/1064857220289040384 https://twitter.com/BenBrelje_says/status/106485722028904038... https://twitter.com/BenBrelje_says/status/1064911958623903744 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

dragonwriter 8y ago

> 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.”