3 ms·

25% sounds super disappointing from a laymans perspective and not very "revolutionary" in the grand scheme of time and space. Can't wait until AI will be able

25% sounds super disappointing from a laymans perspective and not very "revolutionary" in the grand scheme of time and space. Can't wait until AI will be able to iterate advanced engineering designs in simulation space at incredible speed.

grogenaut 4y ago
From 10% to 35% is a 25% improvement, you're still at 35%... From 70 to 95% is a 25% improvement, but it's a lot more. Going from 98 to 99% is only 1% but also like really a 10x improvment. Rockets are operating at pretty decent efficiency, 25% improvment on an internal combusion engine would be mind blowing and make EVs way less interetsting. There are theoretical maximum efficencies for various types of engines due to thermodynamics. You always lose energy to heat. Entropy is a b**.
- Lichtso 4y ago
  Technically, from 10% of something to 35% of something is a 350% improvement or a 25 percent point improvement. https://en.wikipedia.org/wiki/Percentage_point https://en.wikipedia.org/wiki/Percentage_point
  - dotancohen 4y ago
    Actually, from 10% of something to 35% of something is a 250% improvement. You already had the first 10%.
  - grogenaut 4y ago
    yes but people often conflate/confuse that... saying the delta in %'s... not % improvement. I agree with you, I'm attempting to point out how a small % increase is a huge actual improvement. This GP was saying that a 25% improvment in the efficiency of a rocket engine was not much to a layman.
dotnet00 4y ago
Simulations aren't really the limiter on engine efficiency, SpaceX etc already lean heavily on simulations. The limiters on engine efficiency at this point are mostly materials and costs, and even the latter are coming down with better fuels (eg Methane, which is extremely popular with rockets debuting this decade) and different design philosophies (eg SpaceX's Raptor engine, which is supposedly under $1M per engine while being the most advanced flight tested rocket engine out there).
goawaythrwaway 4y ago
[flagged]
Tommstein 4y ago
Agree that 25% doesn't sound very exciting or revolutionary, but computers have been used to design space-related stuff for a while, for example, https://www.jpl.nasa.gov/nmp/st5/TECHNOLOGY/antenna.html https://www.jpl.nasa.gov/nmp/st5/TECHNOLOGY/antenna.html . I would be surprised if no one had tried it with propulsion systems yet.
bandyaboot 4y ago
It’s a big deal because “the tyranny of the rocket equation” works in reverse too. Just as adding fuel is a compounding problem, reducing fuel is a compounding benefit.
- WalterBright 4y ago
  Looking at the size of the rocket that went to the moon vs the size of the rocket that came back from the moon says it all. It seems completely unrealistic to colonize the solar system from earth. The only way is to set up industries on the moon to build the ships and equipment necessary to expand through the solar system.
ClumsyPilot 4y ago
There is never going to be a 100% improvement in 'normal' rockets - you cant gey any more energu out of a chemical reacrion. We are using all the energy that we can get out of the most powerfull fuels that exist. The only two ways to get 'sci-fi style rocket is either nuclear, or to beam energy to the rocket from outside with giant lasers.
- WalterBright 4y ago
  Other ways are: 1. air launch, which boils down to using the O2 in the air rather than carrying it with you 2. mass driver, which needs to be in a vacuum 3. gravity slingshots But, yeah, we need a fusion drive.
  - fbdab103 4y ago
    >2. mass driver, which needs to be in a vacuum Project HARP[0] disagrees. Launched a payload 110 miles (177km) into space using a 120 foot (36m) long cannon. This was in the 1960s. [0] https://en.wikipedia.org/wiki/Project_HARP https://en.wikipedia.org/wiki/Project_HARP
    - WalterBright 4y ago
      It didn't achieve orbit.

grogenaut 4y ago

From 10% to 35% is a 25% improvement, you're still at 35%... From 70 to 95% is a 25% improvement, but it's a lot more. Going from 98 to 99% is only 1% but also like really a 10x improvment. Rockets are operating at pretty decent efficiency, 25% improvment on an internal combusion engine would be mind blowing and make EVs way less interetsting. There are theoretical maximum efficencies for various types of engines due to thermodynamics. You always lose energy to heat. Entropy is a b**.

Lichtso 4y ago
Technically, from 10% of something to 35% of something is a 350% improvement or a 25 percent point improvement. https://en.wikipedia.org/wiki/Percentage_point https://en.wikipedia.org/wiki/Percentage_point
- dotancohen 4y ago
  Actually, from 10% of something to 35% of something is a 250% improvement. You already had the first 10%.
- grogenaut 4y ago
  yes but people often conflate/confuse that... saying the delta in %'s... not % improvement. I agree with you, I'm attempting to point out how a small % increase is a huge actual improvement. This GP was saying that a 25% improvment in the efficiency of a rocket engine was not much to a layman.

dotnet00 4y ago

Simulations aren't really the limiter on engine efficiency, SpaceX etc already lean heavily on simulations. The limiters on engine efficiency at this point are mostly materials and costs, and even the latter are coming down with better fuels (eg Methane, which is extremely popular with rockets debuting this decade) and different design philosophies (eg SpaceX's Raptor engine, which is supposedly under $1M per engine while being the most advanced flight tested rocket engine out there).

goawaythrwaway 4y ago

[flagged]

Tommstein 4y ago

Agree that 25% doesn't sound very exciting or revolutionary, but computers have been used to design space-related stuff for a while, for example, https://www.jpl.nasa.gov/nmp/st5/TECHNOLOGY/antenna.html https://www.jpl.nasa.gov/nmp/st5/TECHNOLOGY/antenna.html . I would be surprised if no one had tried it with propulsion systems yet.

bandyaboot 4y ago

It’s a big deal because “the tyranny of the rocket equation” works in reverse too. Just as adding fuel is a compounding problem, reducing fuel is a compounding benefit.

WalterBright 4y ago
Looking at the size of the rocket that went to the moon vs the size of the rocket that came back from the moon says it all. It seems completely unrealistic to colonize the solar system from earth. The only way is to set up industries on the moon to build the ships and equipment necessary to expand through the solar system.

ClumsyPilot 4y ago

There is never going to be a 100% improvement in 'normal' rockets - you cant gey any more energu out of a chemical reacrion. We are using all the energy that we can get out of the most powerfull fuels that exist. The only two ways to get 'sci-fi style rocket is either nuclear, or to beam energy to the rocket from outside with giant lasers.

WalterBright 4y ago
Other ways are: 1. air launch, which boils down to using the O2 in the air rather than carrying it with you 2. mass driver, which needs to be in a vacuum 3. gravity slingshots But, yeah, we need a fusion drive.
- fbdab103 4y ago
  >2. mass driver, which needs to be in a vacuum Project HARP[0] disagrees. Launched a payload 110 miles (177km) into space using a 120 foot (36m) long cannon. This was in the 1960s. [0] https://en.wikipedia.org/wiki/Project_HARP https://en.wikipedia.org/wiki/Project_HARP
  - WalterBright 4y ago
    It didn't achieve orbit.