6 ms·

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

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.
- technofiend 8y ago
  In my humble opinion swappable batteries on an airplane would run afoul of the maintenance regulations that require an A & P to perform and sign off on changes to the aircraft.
  - Robotbeat 8y ago
    Correct.
  - aphextron 8y ago
    >In my humble opinion swappable batteries on an airplane would run afoul of the maintenance regulations that require an A & P to perform and sign off on changes to the aircraft. Pipistrel Alpha, the only real production electric plane shipping, is using swappable batteries. There's really no other viable way with current technology to have reasonable recharge times.
- Robotbeat 8y ago
  Will not be swappable as that would add too much weight.
- justin66 8y ago
  > 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. There's no particular reason charging a big, multicell battery needs to bottleneck on a single charger. (is there?) It's done with cars for what I always assumed were cost and convenience reasons.
- tristanb 8y ago
  0 volts. See my other comment 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...
deleted 8y ago
[deleted]
ajross 8y ago
> 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.
bluGill 8y ago
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.
- lazerpants 8y ago
  It's a pretty low price. The HondaJet is close at approx. $5MM, though it has more than double the claimed range of the Alice.
- bronco21016 8y ago
  Alice really compares more to large turboprops rather than small jets like the HondaJet. When comparing to the used turboprops on the market the Alice isn’t really that competitive. A used Cessna Conquest with more range could be had for around $1-1.5 million depending on condition. Of course operating expenses are significantly more so someone still needs to figure out the math there. If you’re buying a fleet of new aircraft I suppose it’s competitive but for similar price a Pilatus PC-12 gets you significantly more utility. Land just about anywhere and easily find fuel. Another factor is these MSRP estimates are really hard to pin down before the aircraft is fully developed. In the early 2000s there was a flood of companies claiming $1 million jets. Eclipse Jet being the most notable. Most of those programs either didn’t survive or ended up charging more like $5-10 million. Getting an aircraft certified isn’t cheap and it’s really hard to get economies of scale on something so expensive. I don’t want to completely discount the program but I keep going back to the charging when I try to flesh this idea out. The only possible way I see this succeeding is if the company also facilitates building a charging network. When I was in high school I worked at a small Midwest airport and the idea that the city, who owned the airport, would build charging infrastructure for a niche aircraft is laughable. They almost shutdown their Jet A fueling infrastructure (that they charged money for) because they claimed it was too expensive to maintain. Overall point is that it’s doable but there are hurdles and a half baked idea and marketing fluff is going to result in yet another failed aviation venture.
  - deleted 8y ago

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.

technofiend 8y ago
In my humble opinion swappable batteries on an airplane would run afoul of the maintenance regulations that require an A & P to perform and sign off on changes to the aircraft.
- Robotbeat 8y ago
  Correct.
- aphextron 8y ago
  >In my humble opinion swappable batteries on an airplane would run afoul of the maintenance regulations that require an A & P to perform and sign off on changes to the aircraft. Pipistrel Alpha, the only real production electric plane shipping, is using swappable batteries. There's really no other viable way with current technology to have reasonable recharge times.
Robotbeat 8y ago
Will not be swappable as that would add too much weight.
justin66 8y ago
> 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. There's no particular reason charging a big, multicell battery needs to bottleneck on a single charger. (is there?) It's done with cars for what I always assumed were cost and convenience reasons.
tristanb 8y ago
0 volts. See my other comment 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...

deleted 8y ago

[deleted]

ajross 8y ago

> 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.

bluGill 8y ago

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.

lazerpants 8y ago
It's a pretty low price. The HondaJet is close at approx. $5MM, though it has more than double the claimed range of the Alice.
bronco21016 8y ago
Alice really compares more to large turboprops rather than small jets like the HondaJet. When comparing to the used turboprops on the market the Alice isn’t really that competitive. A used Cessna Conquest with more range could be had for around $1-1.5 million depending on condition. Of course operating expenses are significantly more so someone still needs to figure out the math there. If you’re buying a fleet of new aircraft I suppose it’s competitive but for similar price a Pilatus PC-12 gets you significantly more utility. Land just about anywhere and easily find fuel. Another factor is these MSRP estimates are really hard to pin down before the aircraft is fully developed. In the early 2000s there was a flood of companies claiming $1 million jets. Eclipse Jet being the most notable. Most of those programs either didn’t survive or ended up charging more like $5-10 million. Getting an aircraft certified isn’t cheap and it’s really hard to get economies of scale on something so expensive. I don’t want to completely discount the program but I keep going back to the charging when I try to flesh this idea out. The only possible way I see this succeeding is if the company also facilitates building a charging network. When I was in high school I worked at a small Midwest airport and the idea that the city, who owned the airport, would build charging infrastructure for a niche aircraft is laughable. They almost shutdown their Jet A fueling infrastructure (that they charged money for) because they claimed it was too expensive to maintain. Overall point is that it’s doable but there are hurdles and a half baked idea and marketing fluff is going to result in yet another failed aviation venture.
- deleted 8y ago