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Yeah, but Musk can sell the DoD brand new rockets at full price (i.e. the disposable price), recover the first stage and keep it for himself/sell to more risk-s

Yeah, but Musk can sell the DoD brand new rockets at full price (i.e. the disposable price), recover the first stage and keep it for himself/sell to more risk-seeking third parties like Orbcomm at a deep discount.

mikeash 12y ago
That's the amazing thing about the Falcon 9R: they've managed to build a system where they can basically make a profit testing it. Nobody wants to use second-hand stages until they're proven? No big deal, just keep launching stuff as usual, and recover the first stages and test them until people are happy. At some point, some launch customer will observe that there have been N test launches of reused stages without incident, and thus it's worth buying a launch on one at a lower price. Since SpaceX is making money launching stuff anyway, they can take their time getting to whatever number N turns out to be.
- dm2 12y ago
  I've never thought about that part but you are completely correct, and that is amazing and smart of them to do. The legs and computers are probably not too much more than a bolt-on kit that adds some weight to the rocket, the rocket will still preform as usual and the test is practically free (verses actually testing a new rocket design like other vertical landing rockets have tried).
  - mikeash 12y ago
    Exactly. It does lower the maximum payload by something like 30%, so they can't use it for launching really heavy stuff. But if the customer's payload is within the limit, it just means bolting on legs and adding extra fuel. The total fuel cost of a launch is around $200,000 compared to $60 million total cost for the launch, so the cost of extra fuel is negligible. They've already done it twice (once without the legs and once with) while getting paid to launch payloads. The experimental part doesn't come into play until after the first stage has done its primary job, so there's no additional risk to the customer. This is why I think ongoing comparisons to the Shuttle and other reusable systems are completely wrong. Previous attempts have all been based on much more complicated and expensive vehicles that were expected to compensate by being reused. SpaceX is taking a system that's already one of the cheapest in the business (if not the cheapest?) and making some minor changes to reuse it and make it even cheaper. NASA had to reuse the Shuttle on its second flight ever. SpaceX can keep testing Falcon 9R for as long as customers are willing to pay for launches at their current prices, which looks to be quite a long time.
    - dm2 12y ago
      Look how much will be recoverable in the Falcon Heavy reusable stages, the monetary savings there look massive: http://en.wikipedia.org/wiki/File:Falcon_rocket_family.svg http://en.wikipedia.org/wiki/File:Falcon_rocket_family.svg It seems like such a simple solution to the cost problem (with the attachable reusable legs on existing flights) but I'm amazed that no other rocket company has done it until now, congratulations SpaceX. I guess it was mostly because of the rocket technology (relighting an engine), the new materials (probably carbon fiber legs), and the new/cheap/lightweight computer technologies available today. Hopefully there will be some great videos/pictures from the next test which will land closer to land: http://spaceflightnow.com/tracking/index.html http://spaceflightnow.com/tracking/index.html http://www.orbcomm.com/networks/og2-launch http://www.orbcomm.com/networks/og2-launch
      - mikeash 12y ago
        I think it comes down to how much refurbishment the rocket needs afterwards. The Shuttle reused a lot of expensive hardware, but needed so much work after each flight that it ended up not saving any money. I'd say the odds are good for SpaceX, as it's a much easier problem (no thermal protection system, the engines are a lot less fragile, nothing is being dunked in salt water), but we'll have to see how it really works out. As for why it hasn't been tried before, it seems like the space industry is afraid of doing anything that is somehow short of what's seen as optimal. Rockets are optimized for fuel use by pushing engines and weight to the limit, which is odd because the fuel isn't really expensive. If you're going to cut down on that in the service of another goal like reusability, it seems like they want some huge payoff in exchange. Thus the shuttle ended up as a fancy spaceplane that could bring entire satellites back from orbit, and Rotary Rocket, DC-X, and X-33 were all shooting for single-stage-to-orbit. I don't know how much technology SpaceX is bringing in versus just an attitude that it's OK to be suboptimal, that it's OK to lose payload to reusability, that it's OK to work incrementally and keep throwing away some of your hardware, etc.
        outworlder 12y ago
        Fuel is not expensive. Unless it has to go up the gravity well, then it is.

mikeash 12y ago

That's the amazing thing about the Falcon 9R: they've managed to build a system where they can basically make a profit testing it. Nobody wants to use second-hand stages until they're proven? No big deal, just keep launching stuff as usual, and recover the first stages and test them until people are happy. At some point, some launch customer will observe that there have been N test launches of reused stages without incident, and thus it's worth buying a launch on one at a lower price. Since SpaceX is making money launching stuff anyway, they can take their time getting to whatever number N turns out to be.

dm2 12y ago
I've never thought about that part but you are completely correct, and that is amazing and smart of them to do. The legs and computers are probably not too much more than a bolt-on kit that adds some weight to the rocket, the rocket will still preform as usual and the test is practically free (verses actually testing a new rocket design like other vertical landing rockets have tried).
- mikeash 12y ago
  Exactly. It does lower the maximum payload by something like 30%, so they can't use it for launching really heavy stuff. But if the customer's payload is within the limit, it just means bolting on legs and adding extra fuel. The total fuel cost of a launch is around $200,000 compared to $60 million total cost for the launch, so the cost of extra fuel is negligible. They've already done it twice (once without the legs and once with) while getting paid to launch payloads. The experimental part doesn't come into play until after the first stage has done its primary job, so there's no additional risk to the customer. This is why I think ongoing comparisons to the Shuttle and other reusable systems are completely wrong. Previous attempts have all been based on much more complicated and expensive vehicles that were expected to compensate by being reused. SpaceX is taking a system that's already one of the cheapest in the business (if not the cheapest?) and making some minor changes to reuse it and make it even cheaper. NASA had to reuse the Shuttle on its second flight ever. SpaceX can keep testing Falcon 9R for as long as customers are willing to pay for launches at their current prices, which looks to be quite a long time.
  - dm2 12y ago
    Look how much will be recoverable in the Falcon Heavy reusable stages, the monetary savings there look massive: http://en.wikipedia.org/wiki/File:Falcon_rocket_family.svg http://en.wikipedia.org/wiki/File:Falcon_rocket_family.svg It seems like such a simple solution to the cost problem (with the attachable reusable legs on existing flights) but I'm amazed that no other rocket company has done it until now, congratulations SpaceX. I guess it was mostly because of the rocket technology (relighting an engine), the new materials (probably carbon fiber legs), and the new/cheap/lightweight computer technologies available today. Hopefully there will be some great videos/pictures from the next test which will land closer to land: http://spaceflightnow.com/tracking/index.html http://spaceflightnow.com/tracking/index.html http://www.orbcomm.com/networks/og2-launch http://www.orbcomm.com/networks/og2-launch
    - mikeash 12y ago
      I think it comes down to how much refurbishment the rocket needs afterwards. The Shuttle reused a lot of expensive hardware, but needed so much work after each flight that it ended up not saving any money. I'd say the odds are good for SpaceX, as it's a much easier problem (no thermal protection system, the engines are a lot less fragile, nothing is being dunked in salt water), but we'll have to see how it really works out. As for why it hasn't been tried before, it seems like the space industry is afraid of doing anything that is somehow short of what's seen as optimal. Rockets are optimized for fuel use by pushing engines and weight to the limit, which is odd because the fuel isn't really expensive. If you're going to cut down on that in the service of another goal like reusability, it seems like they want some huge payoff in exchange. Thus the shuttle ended up as a fancy spaceplane that could bring entire satellites back from orbit, and Rotary Rocket, DC-X, and X-33 were all shooting for single-stage-to-orbit. I don't know how much technology SpaceX is bringing in versus just an attitude that it's OK to be suboptimal, that it's OK to lose payload to reusability, that it's OK to work incrementally and keep throwing away some of your hardware, etc.
      - outworlder 12y ago
        Fuel is not expensive. Unless it has to go up the gravity well, then it is.