5 ms·

The little tech firm gunning for an airspeed record

37 points by m-i-l 5y ago

redis_mlc 5y ago
"The Electric NXT or E-NXT is a single-seater aircraft developed by Electroflight and the aerospace giant Rolls-Royce" Not so little.
helsinkiandrew 5y ago
> Electroflight's aircraft will need to sustain almost all of that power output for its entire record-breaking run - around eight minutes. I'm sure this will be an amazing achievement but it seems to be a lot of effort for something that isn't that important - the problem with electric aircraft is endurance rather than top speed. The article seems to acknowledge that at the end: > "For longer flights we are going to need hydrogen or alternative green fuels for a long time yet.
- octopaulus 5y ago
  Not sure what you're trying to say? Light, dense and very powerful electric powetrains need to keep evolving. As we've seen there are very good use cases today for fully electric passenger planes, even for short flights and very good uses case for hybrid planes as well. It's the paramount aspect of electrification, it draws attention, saves weight and reduces costs exactly like battery tech innovations. The reality is that take off is very power intensive as well as other parts of flight. It's very very important.
AKSucks 5y ago
Electric flight for commercial passenger service will never happen at commercial passenger scale. Why? Energy density. Lithium ion batteries store 0.8 MJ per Kg which is fifty three times worse than kerosene. Before you say "oh well but battery tech is getting better every day" - NiMH, a technology now well over forty years old, is about 0.4MJ per Kg. Forty years of battery research has...doubled battery capacity per weight. What seems to be state of the art in commercial battery technology - LG's NCMA - is only about 15-20% ahead of what's in use right now. It gets even more depressing when you realize that Lithium Ion is only barely getting to be one order of magnitude better than lead-acid batteries, a technology that has largely gone unchanged in over a hundred years. We need to have batteries that are a five-fold improvement from what lithium ion brought versus lead acid. You also need a massive amount of power during takeoff and landing. GE's GE90 made about 18MW of power. The most current passenger get engine, the GE9X - produces thrust levels close to the original Soyuz rocket. https://en.wikipedia.org/wiki/Energy_density#/media/File:Energy_density.svg https://en.wikipedia.org/wiki/Energy_density#/media/File:Ene... Kerosene hangs out along with other liquid hydrocarbons as the most energy per weight fuel available to us, around 43MJ/Kg. LNG is a bit better but still in the same ballpark; hydrogen is a three-fold improvement but is a net-negative fuel requiring far more energy to produce than it provides, and a royal pain in the ass to handle. It's safe because it dissipates so rapidly - but the shit loves to permeate everything. Including metal, which usually becomes brittle in the process, something severely incompatible with aviation. Lithium ion battery packs? Barely coming off the Y-axis. Oh, and the aviation industry can't even figure out "lithium ion battery packs for the electrical bus." Fires from said batteries in both Boeing and Airbus are surprisingly common.
- octopaulus 5y ago
  The article didn't make mentions of commercial flights. The cool thing about electric drivetrains is that you can put this specific plane motor in a train... A GE90 is not a rocket engine, nor anything else. Electric powertrain densification, wether electrical, mechanical or electromechanical is a good thing for everybody on earth, similarly to how planes have allowed alot of us to go anywhere. Electric scooter, cars and bikes are helping millions get places reliably, quickly and economically with a clear advantage
  - AKSucks 5y ago
    "The cool thing about electric drivetrains is that you can put this specific plane motor in a train..." Because clearly the railroad industry has been sitting around twiddling its thumbs going "man, how on earth could we make the electric motors we've been using for a century or so, better?" Clearly an electric motor designed for coupling to a turbine or propeller at significant rotational speeds with low/no starting torque, typical lithium ion battery pack voltages, and optimized at great cost for weight....has relevancy for a train where weight and size don't matter, there may be almost zero airflow, the motor often needs to provide massive amounts of starting torque, etc. The railroad industry uses multiple types of electric motors for different applications. The resources companies like Siemens have in refining railway and industrial motors are far greater. The notion that they need a bunch of morons developing a one-off speed record airplane to help them improve their motor tech is absurd. "A GE90 is not a rocket engine, nor anything else. " And what do you suppose the GE LM9000 is? Answer: the aeroderivative gas turbine version of the GE90. Aeroderivative turbines are used extensively in electric power generation and naval power applications. Please stop talking.
    - octopaulus 5y ago
      Ge90 is not a lm9000 :) go to school
- Denvercoder9 5y ago
  > The most current passenger get engine, the GE9X - produces thrust levels close to the original Soyuz rocket. That's off by an order of magnitude. The GE9X produces about 500 kN, while the original Soyuz produced about 4.5 MN at lift-off.

37 points by m-i-l 5y ago

"The Electric NXT or E-NXT is a single-seater aircraft developed by Electroflight and the aerospace giant Rolls-Royce" Not so little.

helsinkiandrew 5y ago

> Electroflight's aircraft will need to sustain almost all of that power output for its entire record-breaking run - around eight minutes. I'm sure this will be an amazing achievement but it seems to be a lot of effort for something that isn't that important - the problem with electric aircraft is endurance rather than top speed. The article seems to acknowledge that at the end: > "For longer flights we are going to need hydrogen or alternative green fuels for a long time yet.

octopaulus 5y ago
Not sure what you're trying to say? Light, dense and very powerful electric powetrains need to keep evolving. As we've seen there are very good use cases today for fully electric passenger planes, even for short flights and very good uses case for hybrid planes as well. It's the paramount aspect of electrification, it draws attention, saves weight and reduces costs exactly like battery tech innovations. The reality is that take off is very power intensive as well as other parts of flight. It's very very important.

AKSucks 5y ago

Electric flight for commercial passenger service will never happen at commercial passenger scale. Why? Energy density. Lithium ion batteries store 0.8 MJ per Kg which is fifty three times worse than kerosene. Before you say "oh well but battery tech is getting better every day" - NiMH, a technology now well over forty years old, is about 0.4MJ per Kg. Forty years of battery research has...doubled battery capacity per weight. What seems to be state of the art in commercial battery technology - LG's NCMA - is only about 15-20% ahead of what's in use right now. It gets even more depressing when you realize that Lithium Ion is only barely getting to be one order of magnitude better than lead-acid batteries, a technology that has largely gone unchanged in over a hundred years. We need to have batteries that are a five-fold improvement from what lithium ion brought versus lead acid. You also need a massive amount of power during takeoff and landing. GE's GE90 made about 18MW of power. The most current passenger get engine, the GE9X - produces thrust levels close to the original Soyuz rocket. https://en.wikipedia.org/wiki/Energy_density#/media/File:Energy_density.svg https://en.wikipedia.org/wiki/Energy_density#/media/File:Ene... Kerosene hangs out along with other liquid hydrocarbons as the most energy per weight fuel available to us, around 43MJ/Kg. LNG is a bit better but still in the same ballpark; hydrogen is a three-fold improvement but is a net-negative fuel requiring far more energy to produce than it provides, and a royal pain in the ass to handle. It's safe because it dissipates so rapidly - but the shit loves to permeate everything. Including metal, which usually becomes brittle in the process, something severely incompatible with aviation. Lithium ion battery packs? Barely coming off the Y-axis. Oh, and the aviation industry can't even figure out "lithium ion battery packs for the electrical bus." Fires from said batteries in both Boeing and Airbus are surprisingly common.

octopaulus 5y ago
The article didn't make mentions of commercial flights. The cool thing about electric drivetrains is that you can put this specific plane motor in a train... A GE90 is not a rocket engine, nor anything else. Electric powertrain densification, wether electrical, mechanical or electromechanical is a good thing for everybody on earth, similarly to how planes have allowed alot of us to go anywhere. Electric scooter, cars and bikes are helping millions get places reliably, quickly and economically with a clear advantage
- AKSucks 5y ago
  "The cool thing about electric drivetrains is that you can put this specific plane motor in a train..." Because clearly the railroad industry has been sitting around twiddling its thumbs going "man, how on earth could we make the electric motors we've been using for a century or so, better?" Clearly an electric motor designed for coupling to a turbine or propeller at significant rotational speeds with low/no starting torque, typical lithium ion battery pack voltages, and optimized at great cost for weight....has relevancy for a train where weight and size don't matter, there may be almost zero airflow, the motor often needs to provide massive amounts of starting torque, etc. The railroad industry uses multiple types of electric motors for different applications. The resources companies like Siemens have in refining railway and industrial motors are far greater. The notion that they need a bunch of morons developing a one-off speed record airplane to help them improve their motor tech is absurd. "A GE90 is not a rocket engine, nor anything else. " And what do you suppose the GE LM9000 is? Answer: the aeroderivative gas turbine version of the GE90. Aeroderivative turbines are used extensively in electric power generation and naval power applications. Please stop talking.
  - octopaulus 5y ago
    Ge90 is not a lm9000 :) go to school
Denvercoder9 5y ago
> The most current passenger get engine, the GE9X - produces thrust levels close to the original Soyuz rocket. That's off by an order of magnitude. The GE9X produces about 500 kN, while the original Soyuz produced about 4.5 MN at lift-off.