OK I get that booster reuse cuts down costs, but the fact is the 2nd stage is still not reused, which limits the economic benefits needed to open new markets. We get a 50% reduction in costs, instead of the 95% reduction in costs.
You can get a 50% reduction in costs just by going to India for launch..
Is SpaceX going for 2nd stage reuse at all? That's going to be a lot harder than booster stage reuse, since you're returning to land at orbital velocity.
And then there's the whole issue of increasing reliability of the 1st stage for reuse hundreds (or thousands) of times needed for new business models...
The first stage represents about 75% of the cost of the vehicle, not 50%. This represents the actual cost of the metal on the launchpad, but not the services around the rocket, including launch control costs, etc.
You can't take a rocket to India and you can't manufacturer that rocket in India (Skilset, US based corporation, ITAR) so you can't achieve your savings that way.
Even Russia - which is using a very old tried and true rocket design - can't match prices at this point. In addition, the budget cuts in Russia have resulted in a massive reduction in reliability, which has blown up their insurance cost recently.
In terms of second stage re-usability, they are looking at that for FalconX, and it's designed in at the start for BFR. Landing something from a second stage is as difficult comparatively vis-a-vis landing the first stage, as landing the first stage was compared to the suborbital hops that Blue Origin is doing.
The latest SpaceX idea (judging by Elon's tweets) appear to be some sort of Ballute based approach.
The first stage re-use should be good for 10 flights without a overhaul, with a complete tear-down on flight 10.
"You can't take a rocket to India and you can't manufacturer that rocket in India (Skilset, US based corporation, ITAR) so you can't achieve your savings that way."
Out of curiosity -- can they _fly_ a rocket to India (maybe have a booster return to India instead of a drone ship ? Too far/out of the way ?
That may not help much since stage 2 would still have to be shipped around, which is probably not cost effective, and there might be other regulations that make it infeasible to launch anywhere but in the USA.
"Is SpaceX going for 2nd stage reuse at all? That's going to be a lot harder"
Yes, they are (and yes, it will be): "SpaceX also continues to study the feasibility of returning and reusing the second stage of the Falcon 9, and Musk said he’s confident it can be done. The question is what “mass penalty” will have to be paid, primarily in terms of the fuel needed to slow the second stage down so that it can make a controlled descent back through Earth's atmosphere.
"Still, Musk believes the Falcon 9 will get to full reusability. In terms of the rocket’s overall cost, the first stage accounts for 60 percent, the upper stage 20 percent, the fairing 10 percent, and the remainder are costs associated with the launch itself (fuel costs are between $300,000 and $500,000), Musk said."
The answer is, this is Falcon 9's final form. You can get it in single or triple core variants.
All new work is now on BFR, which will have 2nd stage reusability, orbital refueling, better economics etc. I think you're also underestimating how far this Falcon will get them - their timelines suggest that this is what they'll use to launch their global internet satellite network, not BFR.
Basically the answer to all of those is SpaceX's next gen BFR rocket. It is scaled up significantly which makes second stage reuse practical. The challenge with a rocket the size of the Falcon 9 is that added significant fixed mass to the second stage (heat shielding, parachutes, etc.) will significantly Affect payload mass / performance.
By going to a much larger class of rocket, those concessions for re-use become a smaller fraction of the total stage 2 mass.
The BFS (spaceship, i.e. second stage) is supposedly going to have enough performance to make orbit on its own as an SSTO, with a tiny payload. It probably won’t ever be used that way, though.
You need supplies to keep those humans alive for a week, and a huge amount of fuel to boost the ship into a moon-intersecting orbit. Not a tiny payload by any means.
To get other BFSes up there with enough fuel to transfer a useful amount would require them to use the first stage booster instead of just being SSTO.
Really there's no point to doing an SSTO launch in practice since the BFR first stage will in theory be just as reusable (if not more so) than the BFS second stage. Using the first stage booster greatly improves payload to orbit and has relatively low marginal cost once you've built and tested the whole system.
For a single launch, sure.
What happens if there are regular launches?
Logistically, to me it seems that it would be a great idea to have a refueling station in orbit which is supplied by BFR cargo ships ..say.. once a month.
Launching a BFR for each launch of BFS would require a lot of transportation and duplicated effort.
Is this intuition wrong?
The plan is that the BFR lands back at the launch pad in the same cradle it launched from which would reduce operational complexity.
The fuel for your station has to get there somehow, and so does the station itself. The BFS-tanker ships would need to be launched with a BFR booster to bring up a meaningful amount of fuel, and there are going to be way more of those than there will be BFS-crew launches (ignoring the Earth-to-Earth transportation segment, where a centralized fuel station wouldn't make sense since each route will take a very different orbital path).
SSTO-ing the BFS-crew would require another BFR booster-plus-cargo launch anyway to replace the fuel and cargo you could have carried up in the BFS if you had launched it on the BFR booster to begin with.
The only angle that makes sense to me for doing a BFS-crew SSTO with minimal payload would be if it is deemed to be less risky for loss-of-crew. In that case you could have a BFS-tanker already on orbit and fully loaded by multiple BFR-plus-tanker launches, ready to rendevous with the BFS-crew ship after it reaches orbit on fumes.
I think that is unlikely though since such a launch might leave the BFS-crew without the fuel margin required to divert or de-orbit and land propulsively without refuelling.
Once your payload exceeds the SSTO capability of a single BFS launch, you save effort by doing a two-stage launch. The two-stage launch is more complex and difficult, but the added capacity is far greater.
For intuition, consider moving to a new house. What’s better, renting a tiny car with room for one suitcase, or renting a big truck? The car is cheaper and easier to drive, but unless all of your stuff fits in one suitcase, the truck is going to be much cheaper and easier for this task.
There is already a plan for a tanker version of the BFS, since as you note it wouldn’t be efficient to refuel with another crewed craft. I don’t see what the station helps with, though. That’s just extra mass to launch.
Managing logistics?
A series of BFR launches to station some fuel in orbit seems like a better choice than having to launch a fuel tanker BFR each time.
Why? I don’t see the advantage. It would make sense if one BFR tanker could launch enough fuel for multiple missions, which you’d then want to store somewhere, but that’s not the case.
Orbit isn't just one thing. The plane changes (some of the most expensive types of burns) involved to get to the same orbit as a tanker and then to the target orbit would vastly outway any potential benefits.
You can get a 50% reduction in costs just by going to India for launch..
Is SpaceX going for 2nd stage reuse at all? That's going to be a lot harder than booster stage reuse, since you're returning to land at orbital velocity.
And then there's the whole issue of increasing reliability of the 1st stage for reuse hundreds (or thousands) of times needed for new business models...