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It's an impressive piece of mechanical engineering. I don't see it as being able to fly without some really aggressive advances in technology. If we stay on o

It's an impressive piece of mechanical engineering. I don't see it as being able to fly without some really aggressive advances in technology. If we stay on our current track then maybe in 200 years we could have a direct conversion compact fusion reactor as the power source of a high-power electric plane. Until then I don't think this could reasonably fly.

Tuna-Fish 5y ago
... and what exactly are you basing any of this on? Battery-powered airplanes are perfectly capable of flight. They are just inefficient for long trips.
- willis936 5y ago
  None of them have 20 MW to feed.
  - Robotbeat 5y ago
    The largest machines humanity has built (typically mining machines) are electric. I don’t see why people think total power is the real limiting factor vs, say, specific power.
    - Tuna-Fish 5y ago
      Specific power is also not a problem. Specific energy is.
      - Robotbeat 5y ago
        Indeed, but the article is about a motor.
        willis936 5y ago
        An aircraft motor*.
  - osigurdson 5y ago
    At the upper end, the largest aircraft engines such as the GE CF6 (used in 747) produce about 40MW [1] and there are 4 of these. [1] https://en.wikipedia.org/wiki/General_Electric_LM6000 https://en.wikipedia.org/wiki/General_Electric_LM6000
    - willis936 5y ago
      The GE CF6 does not use motors for propulsion. The LM6000 is not used in aircraft because it can't be with current technology.
      - osigurdson 5y ago
        The CF6 is a gas turbine engine, not an aircraft. Virtually all aircraft engines outside of very small personal planes are gas turbines. This includes turboprops, helicopter applications, all commercial aircraft (turbofan) as well as fighter jets. The primary difference is how the thrust is used. If mechanical energy is required a power turbine is used - as is done in the LM6000. The LM6000 is the industrial version of the CF6 (the cold section is largely the same). The thrust is converted to mechanical energy using a power turbine. I included this link instead of the CF6 since it provides a direct reference to power output in MW (i.e. not thrust).
  - Tuna-Fish 5y ago
    And if you just look at the state of battery tech, that does not actually look unreasonable to provide. There are commercially available high-energy cells that provide ~900W/kg. That's ~22t for the cells, round up to 30t for the other stuff. Coincidentally, that's roughly similar to the fuel capacity of an A320, to which they compared their engine power. You could push the specific power up quite a lot, but you'd have to start sacrificing specific energy, which is the sticking point of electric airplanes. With those batteries, you only get 5MWh, or you could only provide that 20MW for ~15 minutes. This is not as bad as it sounds, because airplanes only need to provide near their maximum power for relatively briefly. There are many short hop routes where that airplane can operate profitably. Still, it should make clear the point that the deficiency of electric airplanes is not their power, but their range. When you fit a plane with batteries that contain sufficient energy to go anywhere useful, you also provide it with frankly excessive power to run it's engines.
    - SigmundA 5y ago
      >There are commercially available high-energy cells that provide ~900W/kg. Can you please provide more information? My understanding is the best lithium is under 400wh/kg. Edit: Sorry looks like you are talking about power density not energy density (watts vs watt/hours). My understanding is range (energy density) is the problem not power output. Cruise takes about 1/3 the power of takeoff so maybe an hour of flight with 5 Mwh?
onion2k 5y ago
200 years is a little less than twice as long humans have been flying powered aircraft for. It's more than 3 times longer than humans have been putting things in to space for. The idea that you can predict that far in to the future is just silly.
Reason077 5y ago
Of course it will be able to fly. With 20MW of engine power at your disposal you’ll be able to lift an awful lot of batteries. The real question is, how long and how far will it be able to fly? And how much payload?
- bserge 5y ago
  Where's the 20MW from?
  - willis936 5y ago
    The 5th and final line: >Wright will use 10 2MW motors on its Wright 1 aircraft - that's a total of 20 MW, which is as powerful as an A320 Airbus aircraft The blog also links to a "deep dive" with a few more details. https://medium.com/@jeff_60994/wright-has-begun-testing-our-2-mw-aviation-grade-motor-for-transport-category-zero-emissions-79cb01c2cfc6 https://medium.com/@jeff_60994/wright-has-begun-testing-our-...
  - Reason077 5y ago
    > ”Where's the 20MW from?” Quite a few tonnes of batteries, I’d say. But potentially there are other options like fuel cell stacks.
    - PaulDavisThe1st 5y ago
      vs. quite a few tonnes of jet fuel.

Tuna-Fish 5y ago

... and what exactly are you basing any of this on? Battery-powered airplanes are perfectly capable of flight. They are just inefficient for long trips.

willis936 5y ago
None of them have 20 MW to feed.
- Robotbeat 5y ago
  The largest machines humanity has built (typically mining machines) are electric. I don’t see why people think total power is the real limiting factor vs, say, specific power.
  - Tuna-Fish 5y ago
    Specific power is also not a problem. Specific energy is.
    - Robotbeat 5y ago
      Indeed, but the article is about a motor.
      - willis936 5y ago
        An aircraft motor*.
- osigurdson 5y ago
  At the upper end, the largest aircraft engines such as the GE CF6 (used in 747) produce about 40MW [1] and there are 4 of these. [1] https://en.wikipedia.org/wiki/General_Electric_LM6000 https://en.wikipedia.org/wiki/General_Electric_LM6000
  - willis936 5y ago
    The GE CF6 does not use motors for propulsion. The LM6000 is not used in aircraft because it can't be with current technology.
    - osigurdson 5y ago
      The CF6 is a gas turbine engine, not an aircraft. Virtually all aircraft engines outside of very small personal planes are gas turbines. This includes turboprops, helicopter applications, all commercial aircraft (turbofan) as well as fighter jets. The primary difference is how the thrust is used. If mechanical energy is required a power turbine is used - as is done in the LM6000. The LM6000 is the industrial version of the CF6 (the cold section is largely the same). The thrust is converted to mechanical energy using a power turbine. I included this link instead of the CF6 since it provides a direct reference to power output in MW (i.e. not thrust).
- Tuna-Fish 5y ago
  And if you just look at the state of battery tech, that does not actually look unreasonable to provide. There are commercially available high-energy cells that provide ~900W/kg. That's ~22t for the cells, round up to 30t for the other stuff. Coincidentally, that's roughly similar to the fuel capacity of an A320, to which they compared their engine power. You could push the specific power up quite a lot, but you'd have to start sacrificing specific energy, which is the sticking point of electric airplanes. With those batteries, you only get 5MWh, or you could only provide that 20MW for ~15 minutes. This is not as bad as it sounds, because airplanes only need to provide near their maximum power for relatively briefly. There are many short hop routes where that airplane can operate profitably. Still, it should make clear the point that the deficiency of electric airplanes is not their power, but their range. When you fit a plane with batteries that contain sufficient energy to go anywhere useful, you also provide it with frankly excessive power to run it's engines.
  - SigmundA 5y ago
    >There are commercially available high-energy cells that provide ~900W/kg. Can you please provide more information? My understanding is the best lithium is under 400wh/kg. Edit: Sorry looks like you are talking about power density not energy density (watts vs watt/hours). My understanding is range (energy density) is the problem not power output. Cruise takes about 1/3 the power of takeoff so maybe an hour of flight with 5 Mwh?

onion2k 5y ago

200 years is a little less than twice as long humans have been flying powered aircraft for. It's more than 3 times longer than humans have been putting things in to space for. The idea that you can predict that far in to the future is just silly.

Reason077 5y ago

Of course it will be able to fly. With 20MW of engine power at your disposal you’ll be able to lift an awful lot of batteries. The real question is, how long and how far will it be able to fly? And how much payload?

bserge 5y ago
Where's the 20MW from?
- willis936 5y ago
  The 5th and final line: >Wright will use 10 2MW motors on its Wright 1 aircraft - that's a total of 20 MW, which is as powerful as an A320 Airbus aircraft The blog also links to a "deep dive" with a few more details. https://medium.com/@jeff_60994/wright-has-begun-testing-our-2-mw-aviation-grade-motor-for-transport-category-zero-emissions-79cb01c2cfc6 https://medium.com/@jeff_60994/wright-has-begun-testing-our-...
- Reason077 5y ago
  > ”Where's the 20MW from?” Quite a few tonnes of batteries, I’d say. But potentially there are other options like fuel cell stacks.
  - PaulDavisThe1st 5y ago
    vs. quite a few tonnes of jet fuel.