3 ms·

Merlin is also the highest thrust-to-weight engine ever, by a large margin. F-1 could produce a lot of thrust because it was huge, not because it was efficient.

Merlin is also the highest thrust-to-weight engine ever, by a large margin. F-1 could produce a lot of thrust because it was huge, not because it was efficient. But that's stuff they've already accomplished. You're ignoring what they have in development. The Raptor engine is among the most advanced engines ever made, pushing combustion/metallurgy technology literally to the limits, certainly not well-worn ground. Not to mention Starship/Super Heavy, which is pushing reusability further. They might not accomplish everything they set out to do, but that's why it's "pushing" rather than "pushed".

rayiner 8y ago
> Merlin is also the highest thrust-to-weight engine ever, by a large margin. F-1 could produce a lot of thrust because it was huge, not because it was efficient. It's about twice the thrust-to-weight ratio of an F-1, which was designed in 1969. With all the advances in materials science since 1969 (composites, etc.), that tells you a lot about the glacial pace of advancement in the field. It's also not clear to me why that even matters--a Saturn V has about 90,000 pounds of engines; a Falcon 9 Heavy has about 27,000 pounds. Both need millions of pounds of fuel. (As to your comment about "pushing" versus "pushed"--that interpretation of OP's comment doesn't match the fact that he's talking about a setback involving SpaceX's current generation of vehicles.)
- ddalex 8y ago
  Mate, not everything in the world moves as fast as the Javascript ecosystem. There are some hard laws at hand, called physics, that limit what you can lit under a rocket and get propulsion. Oxygen needs to be there. A combustible needs to be there as well. This is known since the 19th century. It just turns out that RP-1 is a good choice. Given the same chemical reaction, improving the engine efficiency state-of-art by 50% in 50 years is astounding. With Raptor they are actually getting close to the theoretical limits. What other expectations do you have for advancements? New chemicals are hard to get by. Nuclear is beyond contemplation. You can't invent new physics. What do you expect?
  - rayiner 8y ago
    I have a degree in aerospace engineering, so I'm quite aware of all these limitations. What irks me about SpaceX is Silicon Valley-style marketing ("pushing the boundaries of spaceflight technology") being imported into what is in reality an extremely mature field where we have hit some pretty hard walls on possible advances. It's also immensely disrespectful to the folks who designed this technology two generations ago (back when it wasn't already proven), to act like you're "pushing the boundaries" when the main thing you're doing is cost-optimizing well-established designs.
    - ddalex 8y ago
      However they are pushing the boundaries in terms of cost per pound to LEO, in terms of reusability, and in terms of scale (what classic system launches with 27 engines firing!?!). So while you may not like it, they do all of what they claim. Through aerospace innovation? Perhaps not as much as you would like. But they do it through materials, manufacturing, automation, computers and operations innovations, which are just as important.
- gliptic 8y ago
  Then I don't know why you brought up Merlin at all because there's no Merlin engines involved in this anomaly. The Crew Dragon is not as revolutionary as other things they're doing, but it does have an integrated abort system that hasn't been done before as far as I know.

rayiner 8y ago

> Merlin is also the highest thrust-to-weight engine ever, by a large margin. F-1 could produce a lot of thrust because it was huge, not because it was efficient. It's about twice the thrust-to-weight ratio of an F-1, which was designed in 1969. With all the advances in materials science since 1969 (composites, etc.), that tells you a lot about the glacial pace of advancement in the field. It's also not clear to me why that even matters--a Saturn V has about 90,000 pounds of engines; a Falcon 9 Heavy has about 27,000 pounds. Both need millions of pounds of fuel. (As to your comment about "pushing" versus "pushed"--that interpretation of OP's comment doesn't match the fact that he's talking about a setback involving SpaceX's current generation of vehicles.)

ddalex 8y ago
Mate, not everything in the world moves as fast as the Javascript ecosystem. There are some hard laws at hand, called physics, that limit what you can lit under a rocket and get propulsion. Oxygen needs to be there. A combustible needs to be there as well. This is known since the 19th century. It just turns out that RP-1 is a good choice. Given the same chemical reaction, improving the engine efficiency state-of-art by 50% in 50 years is astounding. With Raptor they are actually getting close to the theoretical limits. What other expectations do you have for advancements? New chemicals are hard to get by. Nuclear is beyond contemplation. You can't invent new physics. What do you expect?
- rayiner 8y ago
  I have a degree in aerospace engineering, so I'm quite aware of all these limitations. What irks me about SpaceX is Silicon Valley-style marketing ("pushing the boundaries of spaceflight technology") being imported into what is in reality an extremely mature field where we have hit some pretty hard walls on possible advances. It's also immensely disrespectful to the folks who designed this technology two generations ago (back when it wasn't already proven), to act like you're "pushing the boundaries" when the main thing you're doing is cost-optimizing well-established designs.
  - ddalex 8y ago
    However they are pushing the boundaries in terms of cost per pound to LEO, in terms of reusability, and in terms of scale (what classic system launches with 27 engines firing!?!). So while you may not like it, they do all of what they claim. Through aerospace innovation? Perhaps not as much as you would like. But they do it through materials, manufacturing, automation, computers and operations innovations, which are just as important.
gliptic 8y ago
Then I don't know why you brought up Merlin at all because there's no Merlin engines involved in this anomaly. The Crew Dragon is not as revolutionary as other things they're doing, but it does have an integrated abort system that hasn't been done before as far as I know.